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No. 3:i.— OCT<HJKR, 1904

DEPARTMENT OF THE INTERIOR

BUREAU OF GOVERNMENT LABORATORIES
BIOLOGICAL LABORATORY

The Plague: Bacteriology, Morbid
Anatomy, and Histopathology

INCLUDING A CONSIDERATION OF INSECTS
AS PLAGUE CARRIERS

or

Maximilian Herzog, M. D.

MANILA

BUREAU OF PUBLIC PRINTING

1904
25483

LETTERS OF TRANSMITTAL

Department of the Interior,
Bureau of Government Laboratories,
Office of the Superintendent of Laboratories,

Manila, October 20, 190 J^.
Sir : I have the honor to transmit herewith an article entitled
"The Plague: Bacteriology, Morbid Anatomy, and Histopatholog}^
(including a consideration of insects as plague carriers),"' by
Maximilian Herzog, M. D.

I am, very respectfully,

Paul C. Freer,
Superintendent. Government Laboratories.

Hon. Dean C. Worcester,

Secretary of' the Interior, Manila, P. I.

Department of the Interior,
Bureau of Government Laboratories,
Biological Laboratory, Office of Director,

Manila, October 19, 190Jf.
Sir : I have the honor to transmit herewith and to recommend
for publication a report entitled "The Plague : Bacteriology, Morbid
Anatomy, and Histopathology (including a consideration of insects
as plague carriers)," "by Dr. ]\Iaximilian Herzog, pathologist
Biological Laboratorv.

Very respectfully, Richard P. Strong,

Director Biological Laboratory.
Dr. Paul C. Freer,

Superintendent Government Laboratories.

3

TABLE OF CONTENTS.

Page.

List of illustrations "

Preface .^ ^

The discovery of the plague bacillus H

Morphology of the plague bacillus 13

Cultivation of the plague bacillus 16

Nosology and classification 19

The morbid anatomy and histopathology of plague as described in

literature 23

A study of twenty cases of bubonic plague 41

Group I: Primary uncomplicated bubonic plague 42

Insects as plague carriers 74

A new species of rat tlea , "7

Experiments with flies "9

A case of bubonic plague in a child, in which the infection was possi-
bly carried by pediculi 80

Group II: Primary bubonic plague with secondary plague septico-
pyemia 8"

Group III : Primary bubonic plague with secondary plague pneumonia 102

Ambulatory plague or pestis minor. 102

Group IV : Primary uncomplicated plague pneumonia 108

Group Y : Primary plague pneumonia with secondary plague septico-
pyemia 113

Group VI: Primary plague septicaemia 11"

Analysis of the twenty cases reported and summary of the patholog-
ical findings 121

Portal of entrance of the virus 122

Period of incubation 122

The lymph glands in bubonic plague 123

Fibrin formation in the glands and in other organs 125

Hemorrhages into the bubo and into the distant organs 125

Plague as a rule not a general microbic infection 127

The infection of the spleen 128

The extension of the prima.ry bubo 128

The other lymph glands 129

The heart and the circulatory system 129

The lungs 131

The spleen - 132

The genito-urinary system 133

Hyaline fibrin thrombi of the glomerular capillaries 133

The urine in plague 13'

The liver and the gall bladder 139

The stomach and the intestines 140

Steps in establishing the post-mortem diagnosis in plague 140

References to literature 145

5

LIST OF ILLUSTRATIONS.

FiCiUKE 1. Ilemorrhagif inguinal bubo. (FigH. 1 to 5 are drawn from nature
.from post-mortem specimens preserved in Kaiserling'n fluid.
All except fig. 3, which is reduced one-half, are natural size. )

2. Heart in a case of bubonic plague, showing subepicardial hemor-

rhages.

3. Stomach in a case of l)ubonic plague, showing submucous hemor-

rhages.
4, 5. Kidney in a case of bubonic plague, showing subcapsular and pel-
vic hemorrhages.

6. Culture of plague bacillus on agar, five daj's' growth, fixed with

formalin vapors.

7. Colony of a plague gelatin plate culture, forty-eight hours old

(Zeiss A A ocular No. 3), showing the dark, elevated center and
the homogeneous marginal zone.

8. Cover-glass preparation from a twenty-four-hour-old agar plague

culture; stained with dilute carbol-fuchsin.

9. Same, showing typically stained bacilli and also uniformly stained

involution forms.

10. Same, from a sixteen-day-old glycerin-agar culture; club-shaped

involution forms.

11. Same as fig. 10, spermatozoa-like involution forms.

12. Same, from a three-day-old 4 per cent salt-agar culture; yeast-shaped

involution forms.

13. Pof-t-mortem smear from a plague bubo.

14. Post-mortem smear from the spleen in a case of bubonic plague.
15, 16. Post-mortem smears from a case of plague pneumonia. (Necropsy

No. 971.)

17. Post-mortem smear from the heart's blood in necropsy No. 973,

showing one plague bacillus in the center of the field. (X
2,000. )

18. Section of inguinal lymph gland from necropsy No. 901, showing

dilated blood vessels.

19. Section of submental gland, necropsy No. 928. Near the center

of the field may be seen a plasma mast cell surrounded by dense
zo(")gleal masses of plague bacilli.
20-23. Sections of the kidney; hyaline fibrin thrombosis of the glome-
rular vessels.

24. Section of lung from necropsy No. 901; tubercle witli giant cell.

This tubercle showed an infection with plague bacilli.

25. Section from the liver in necropsy No. 901. Infiammatory focus

with many eosinophilic leucocytes.
2(5. Pulex philippinensis, species nova — the flea found on rats in

Manila; male.
27. The same, female.

THE PLAGUE: BACTERIOLOGY, MORBID ANATOMY, AND

HISTOPATHOLOGY.

(INCLUDING A CONSIDERATION OF INSECTS AS PLAGUE CARRIERS.)

By Maximilian Herzog, M. D., Pathologist Biological Laboratory.

PREFACE.

The "Great Black Death/' the most dreaded scourge of the
Middle Ages — the grim reaper who, as is estimated, in the four-
teenth century, within three years, carried away in Europe twenty-
five millions of people — had, as it seemed, vanished from the surface
of the globe, when about ten years ago a new great pandemic of
plague, which still persists, appeared in China and India. From
here it made excursions into London, Oporto, Glasgow, Triest,
Alexandria, Sidney, Hamburg, Bremen, and Naples — however
(thanks to the modern methods of meeting infectious and contagious
diseases), without there gaining a foothold or assuming dangerous
epidemic proportions.

At present the dreaded disease has not merely reached our own
Far Eastern, transoceanic possessions — the Philippine Islands — but
it has even established itself endemically in California at San
Francisco. While it is to be hoped that with proper, vigilance and
with a continuous, untiring practice of the prophylactic measures
which we are taught by modern hygiene the plague may never
assume dangerous epidemic proportions, either in the Philippines
or in the United States, we have every reason to keep it in view
and to study it carefully in all of its phases. Therefore we need
not apologize for offering in this bulletin a contribution to the
bacteriology, morbid anatomy, and histopathology of plague as
gained from both a perusal of literature and more particularly from

9

10

a stud}' of a nrnnber of cases which came to post-mortem examina-
tion in Manila.

It has been nw purpose in the preparation of this report to
furnish a scientific contribution to the subject and to bring out,
if possible, some new points, which might be of interest and value.
However, another practical object has never been lost sight of,
namely, to provide a guide for those who might be called upon to
make a post-mortem diagnosis of the first case of suspected plague
in a district. This will always be a matter of great responsibility
and sometimes one of considerable difficulty. Unless circumstances
compel the contrary, the diagnosis of a plague case, being the
first of its kind in a communit}', on board of a ship, etc., should be
confirmed by one well trained in general pathology and bacteriology ;
or, still better, by one also having experience in the recognition and
examination of plague cases.

The importance of promptly diagnosing the first case of plague
can not be overestimated. This disease does not make its initial
appearance as a widespread epidemic, as is often the case Avith
Asiatic cholera, when caused by a contaminated water supply or
from other sources of infection. Eather, it begins very insidiously
from one or several imported cases. It is frequently easy to hold
the plague in check, provided it is recognized and properly fought
at an early stage. This has been proved by the observations made
in the cities mentioned above and in Manila.

In studying the histopathology of plague a highly interesting
change was found in the kidneys, namely, extensive and frequently
occurring hyaline fibrin thrombosis of the glomerular capillaries.
As it appears that this change has not been described in the study
of the microscopic anatomy of the disease, it has been considered
somewhat at length. The histologic examinations in their entirety
have led to the conviction that plague in its most common bubonic
type should not be looked upon as a hemorrhagic septicemia,
because according to all appearances the infecting bacilli remain
practically localized until the agonal stage of the disease is reached.

One of the cases examined and herein reported in detail sug-
gested the possibility, if not the probability, of an infection through
the agency of pediculi. This led to the study of the role which
insects may play as carriers of plague. The ones which have
been accused particularly of being the most important, factors in

11

spreading jolague from rats to men are the rat fleas. In taking
up this question with reference to local conditions, it was found
that these rodents in Manila are infested by a species of sipho-
naptera not heretofore described. It, however, appears that this
new species of flea has not taken any part in the conveyance of
the disease, which may or may not have been first imported to
this city through the agency of rats.

It is a source of great satisfaction to the writer to be in a
position to present this paper well illustrated with colored plates,
photographs, and microphoto graphs, by which whatever value it pos-
sesses, both as a scientific contribution and as a guide in the post-
mortem diagnosis of plague, is undoubtedly greatly enhanced.

For a revision of the manuscript the author is indebted to Drs.
Paul C. Freer and Eichard P. Strong. The colored drawings
were prepared by Mr. T. Espinosa and Mr. W. Schultze and most
of the microphotogra|)hs by Mr. Chas. Martin, all members of our
laboratory staff.

THE DISCOVERY OF THE PLAGUE BACILLUS.

The etiologic factor of plague in all of its various forms is
a specific micro-organism — the j^lague bacillus. It can generally,
without difficulty, be cultivated in pure culture from cases of
plague in man. In susceptible animals it produces a disease
identical with or similar to that found in the human race, and in
some deplorable laboratory accidents, in locations where no plague
existed, it has caused typical fatal pest infection in men. The
names both of Yersin and of Kitasato are connected witli the
discovery of the plague bacillus during the epidemic in Hongkong
in 1894. To the claims of each of these investigators to be the
independent discoverer of the plague germ one may well apply
the words of the German poet, that it is "Von den Parteien Hass
und Gunst entstellt."

Some writers upon plague dispute Yersin's claim; while not
a few, and particularly his own countrymen, maintain that Kita-
sato is not entitled to any fame in connection with the original
finding of Bacillus pestis. Ogata, for instance, tersely states:

Many aiitiiors believe that tlie plague bacillus of Kitasato and that of
Yersin are identical, but svich is not tlie case. They are two absolutely
different kinds of bacilli.

12

And then Ogata as well as Yamagiwa, in another publication,
shows that they found the Yersin bacillus as the cause of the
plague in the Formosa epidemic. Scheube equally opposes Kita-
sato's claim and says :

The bacillus discovered simultaneously and at the same place by Kitasato
is not the true plague bacillus (discovered by Yersin), because it shows
marked points of difference, it is motile, etc.

It is a somewhat ludicrous misfortune which befalls Scheube
in his polemical remarks against Kitasato, that he himself con-
fuses some of the differentiating characters of Yersin's and Kita-
sato's first descriptions. Scheube makes it appear as if Kitasato
at first erroneously stated that the plague bacillus does not and
that Yersin's bacillus does retain Gram's stain. The opposite,
of course, is true. Yersin correctly, in his first report, stated that
the plague bacillus loses Gram's stain.

On the other hand, Cantlie, of the Indian Medical Service, at
a plague conference and discussion held in London in 1898 observed
that the names of Kitasato and Yersin were usually associated,
and the bacillus was commonly termed the Kitasato-Yersin bacil-
lus. Kitasato, however, had demonstrated the bacillus a week
previous to Yersin, and although he (Cantlie) felt the greatest
respect for the work of Yersin on plague, yet the latter had no
claim as an independent discoverer of the bacillus, since that
distinction belonged to Kitasato alone. (Brit. Med. Jour., 1898,
Vol. II, Sept. 24, p. 963.)

However, anyone who reads the reports of Yamagiwa and Ogata
regarding the epidemic in Formosa, which contain literal trans-
lations from Kitasato's first publications in Japanese, can not
fail to conclude that it was indeed Yersin and not Kitasato who
had first worked with pure cultures of the plague bacillus. Kita-
sato's first reports show clearly that what he described as pure
cultures of the plague bacillus were not such. On the other hand,
there can be no reasonable doubt that Kitasato saw and recognized
plague bacilli shortly before Yersin. No bacteriologist examining
the juice of buboes in certain stages, either from the living or
from the post-mortem table, can overlook the enormous number
of characteristic bacilli. However, it was undoubtedly Yersin who
first isolated and described what was really a pure culture of the
plague bacillus.

13

Yersin's first published description was submitted to the French
Academy and reads as follows:

The first bacteriologic researches were made on living subjects. An
examination of the blood drawn from the finger at various periods of the
disease failed to show the microbes, and the inoculations remained sterile.
The buboes, on the contrary, contained an abundance of a pure culture of
a very small, short bacillus, with rounded ends, which does not stain by
Gram's method, but does with Gentian violet. I have found this bacillus
in buboes of eight patients, and in two plague autopsies I have foimd the
same microbe. It is particularly numerous in the buboes, less abundant
in the other (lymphatic) ganglions, and very rare in the blood at the
moment of death. The liver and spleen are increased in size and contain
the specific bacillus.

A short account of some animal experiments with post-mortem
findings forms the conclusion of Yersin's first report. The second
one gives an equally correct — in some respects more elaborate —
description of the bacillus, of its cultivation, and of animal experi-
ments. Kitasato, in his first description in the London Lancet
(August 25, 1894), states that the bacilli are to be found in the
blood, in the buboes, in the spleen, and in all the internal organs
of the victims of the disease.

I am at present [he says] unable to say whether or not Gram's double-
staining method can be employed. The bacilli show very little movement.

Metschnikoff's standpoint in the controversy as to the discovery
of the plague bacillus is perhaps the most correct and the most
impartial one, hence we quote his words in the language of the
original. He says :

Yersin apres des recherches laborieuses eifectu6es dans des conditions
particulierement difficiles, decouvrit le microbe pesteux. Independamment
de lui Kitasato arrivait au meme resultat. Le savant japonais s'est born6
a communiquer quelques notes preliminaires sur ce sujet, tandis que Yersin
en a poursouvi I'etude avec perseverance; c'est done a lui que nous devons
le meilleur de nos connaissances actuelles sur la peste.

MORPHOLOGY OF THE PLAGUE BACILLUS.

The bacillus pestis is quite variable in its morphology, and it
is important to remember this fact in connection with the bac-
teriologic diagnosis of the disease. In post-mortem smears prepared
from a recent nonsuppurating primary bubo, from a pneumonic
focus, from the spleen, and occasionally from other internal organs
one generally finds numerous plague bacilli. In those from the

14

primary IdiiIjo and from the pneumonic foci their number is legion.
In smears from the spleen thev are fairly abundant, while in
preparations from the other organs, according to our own experi-
ence, they are generally present only to a moderate extent, unless
septico-pyemic metastatic foci should have been established, when
they may be quite numerous. In smears prepared from the heart's
blood we have always found very few bacilli, even in pneumonic and
septico-p3'emic cases.

As a routine method for the examination of smears we have
adopted the following procedure: The preparations were made
during the post-mortem examinations on slides, and these, as soon
as air-dr}^, were placed in a wide-mouthed bottle containing absolute
alcohol. Here they remained until after the termination of the
autopsy, when they were stained with dilute carbol-fuchsin (1 part
of the original stain to 5 to 10 aqua destillata) for twenty to forty
seconds, and then freely washed with water. They were next
immediately examined with oil-immersion magnification. If it
was found that the stain was not satisfactory, being either too light
or too heavy, the immersion oil was washed off in xylol and the
shortcomings corrected either by a second prolonged dyeing or by
rapid immersion in alcohol, followed by washing in water. How-
ever, after a little practice it is soon possible correctly to estimate
the time necessary to bring about that particular stain which will
best show the characteristic morphologic features of the bacillus,
and a second attempt is rarely necessary. If after the first
examination of the slides it is desirable to preserve them for future
reference, the immersion oil is washed off in xylol and the speci-
mens may now be mounted permanently in Canada balsam, being
protected by a cover slip.

In smears made from the organs the j)lague organism appears
as a rather short, plumjj bacillus, being 1.5 to 1.15 fx, long and
0.5 to 0.75 /A thick; generally the proijortion of width to length is
as one to two. Individuals considerably longer than 1.75 ju, are
occasionally seen. The bacilli are generally single, occasionally
diplobacilli are encountered, and very rarely short chains. In
smears which have been fixed in absolute alcohol and which have
been jDroperly dyed the bacilli are not uniformly colored, but they
show a distinct polar staining. Frequently the whole periphery of
the bacillus is stained and only the center has remained uncolored.
Other forms of the organism, while differing in certain respects

15

from the above-given description and while not representing the
most characteristic type, are so frequently fonnd in smears that
the student of plague must thoroughly familiarize himself with
them. These are elliptical or egg-shaped, or almost spherical, and
they show only a very narrow peripheral staining, or they may not
stain at all; hence they look like mere empty shells, which indeed
they jjrobably are, since they are most commonly found in older
'buboes. Also, in smears from cases which have succumbed only
after several days' sickness, one frequently sees various involution
forms of the plague micro-organism, which aj)pear like yeast
cells or which are either quite hazy and indistinct or club shaped
and irregular in outline. Sata has shown that such involution
forms may be seen on and after the fourth day in experimental
plague infection in animals. In cover-glass preparations from
jDure cultures the bacilli are not so characteristic as we find them in
smears from human plague cases, except in some involution forms
to be more fully described below. The first generation, as a rule,
shows the polar staining and the unstained center fairly well, but
in subsequent ones these features often become more or less indis-
tinct, or may even entirely be lost. Plague bacilli from pure
cultures, particularly from the water of condensation of agar
tubes, or from bouillon, frequently show shorter or longer chains,
in which dividing lines between the individual bacilli are so
indistinct as to cause them to appear like filaments. Involution
forms are likewise liable to present themselves early even on
favorable media. We have occasionally seen them as soon as the
second or third day on agar tubes.

The plague bacillus may be stained with any one of the watery
solutions of the common basic aniline dyes. The carbol-thionin
stain, frequently mentioned in connection with it, is not to be
recommended if one works in the Tropics, since for certain reasons
it is very liable to fade. IvosseFs modification of Eomanowsky's
stain has not been very satisfactory in our hands, and for general
practical purposes we have found dilute carbol-fuchsin used in
the manner above recommended the most simple and most imiformly
relialjle.

The plague bacillus, if treated by Gram's method, is decolorized.

The bacillus, if grown in the animal body, possesses a capsule,
which, however, is not very eas)' to demonstrate unless thin spreads
are prepared and fixed in alcohol with great care. There is nothing

16

chracteristic in the capsule^ so its exhibition will not assist in the
microscopic diagnosis of plague. The bacillus is not motile, does not
possess any flagellse, nor has spore formation been observed. Even
if one occasionally sees in the bacilli bodies some^yhat like spores,
they are not genuine spores, because such bacilli are not more
resistant to heat, antiseptics, etc., than the other pest bacilli.

CULTIVATION OF THE BACILLUS.

The plague bacillus grows on all ordinary laboratory culture
media, best on such as are faintly alkaline. Even a minor degree
of acidity as well as a higher degree of alkalinity prevents its
development. It develops at temperatures ranging from 5° to
38° C, and in our artificial media best at 25° to 30° C. It is
quite strictly, though perhaps not absolutely, obligate aerobic.
As a rule it develops on artificial media only in the presence of
free oxygen. However, some observers have occasionally seen a
weak growth even in the absence of the latter. When a favorable
solid culture medium (agar or gelatin, slightly alkaline) is inoculated
from the organs (bubo, spleen, etc.) of a plague case, the develop-
ment of the plague bacilli is at first generally quite slow, and
frequently very little can be seen with the naked eye within the
first twenty-four hours. On the other hand, in a considerable
number of cases a tjqjical picture may appear after this time and it
is always present after forty-eight hours. The surface of the agar or
gelatin shows small, delicate, round, moist, dewdrop-like colonies.
They are light gray in refiected light and grayish-white in transmit-
ted. If these colonies are inspected with a hand lens or with a lower
power of the compound microscope they show an elevated, finely
granular, rounded center and a perfectly transparent, very thin,
flat marginal zone. The colonies on the whole are circular, but the
transparent marginal zone early shows a somewhat irregular
boundary line. Colonies of this type are not formed by any other
micro-organism, except occasionally by the influenza bacillus. How-
ever, in the case of the plague bacillus they develop most characteris-
tically on ordinary gelatin plates kept at 20° to 24° C, under
which conditions the influenza bacillus would not show any growth
at all. While these typical young colonies are seen both on agar and
on gelatin, we think that they are best shown on the latter, hence
the use of this medium is to be greatly recommended in the bac-
teriologic diagnosis of plague. Gelatin plates can, of course, be

17

used in the Tropics only where an incubator with cooling device is
at hand. If an impression preparation is made of one of the young
colonies with a homogeneous, transparent, marginal zone, it is seen
that this consists of bacilli arranged in curved filaments. If the
inoculation from the organs has been quite rich in plague bacilli
the surface between the colonies has a ground-glass appearance,
which becomes more marked after forty-eight hours, and is generally
well seen in cultures a few days old. After three or more days the
erstwhile very delicate colonies become larger, more granular, and
less transparent. The marginal zone likewise has become thickened,
is less homogeneous, and its edges become more irregular and are
often finely serrated at the periphery. The colonies now have a
more decidedly grayish-white appearance and occasionally show a
slight tinge of yellow. In young cultures of the first generation
colonies are usually small, grow slowly and remain comparatively
small, occasionally^ however, rapidly attaining a diameter of several
millimeters. We have several times seen such large colonies where
the material from which an inoculation was made contained few
bacilli and where subsequently only a few colonies developed. How-
ever, this is probably not the only condition under which the large
ones make their appearance. Older cultures of the plague bacillus,
particularly when they have in consequence of evaporation become
dry and quite granular, are somewhat iridescent. If a young
plague culture is touched with a platinum loop it is found to be
viscous and sticky. It is, however, easily removed from the surface
on which it grows.

The plague bacillus, as stated before, early in its growth has a
marked tendency to develop involution forms. As first shown by
Hankin, this tendency is most pronounced in cultures on a 3 to 4
per cent salt agar. Hence we have in this medium one of the
most valuable means for the bacteriologic diagnosis of plague. It
is prepared and standardized like any ordinary agar, only that it
does not merely contain one-half but 3 to 4 per cent of common
salt. Hence, in case of an emergency, salt agar can be prepared
from the ordinary media by the addition of the proper amount
of NaCl to bring it up to the desired concentration. We have found
it best to use a 3.5 to 4 per cent salt agar and not to diminish this
percentage. On a medium of this concentration, particularly if it
is fairly dry and contains very little water of condensation, involu-
25483 2

(

18

tion forms of the plague bacillus are seen after twenty-four hours
Generally the greater number, or all, of the organisms from such a
growth present themselves as large spherical bodies, looking very
much like yeast cells ; later, large swollen club or dumbbell shaped,
spermatozoa-like or irregular forms make their appearance. The
most typical, and the most constant form on a 3.5 to 4 per cent
salt agar, after twenty-four to forty-eight hours, is the yeast-like,
large, spherical plague organism. There is no micro-organism
which forms this type so promptly and so regularly on salt agar
and which might be confounded with the plague bacillus. Hence
it is advisable in a first suspected plague case at the autopsy to
inoculate besides gelatin plates also ordinary agar tubes, bouillon
flasks, and salt agar tubes or plates. In bouillon flasks the bacilli,
at temperatures between 30° and 35° C, after twenty-four hours,
show a finely flocculent whitish, slowly increasing sediment. During
the next twenty-four hours the flocculi extend upwards from the
bottom along the walls. A fine whitish ring of growth then forms
on the surface and in course of time covers it. If the flask, is
protected from any motion and kept perfectly undisturbed, bands
and strands of bacilli finally grow downward from the surface
membrane. The contents of the flask now present an appearance
which somewhat reminds one of stalactite and stalagmite formation
A slight jar sends the stalactites to the bottom and destroys the
characteristic appearance. The stalactite formation can be assisted
by floating on the surface of the bouillon a few drops of an indifi erent
substance, such as butter, olive or cocoanut oil, small pieces of
cork, splinters of wood, etc. Of course, these. bodies should be
added to the bouillon before sterilization. The bouillon used in
connection with our plague w^ork has been one of a flxed degree of
alkalinity recommended particularly by Kossel and Overbeck as
most favorable for the development of the plague bacillus. Such
a bouillon is prepared in the ordinary manner and alkali is added
until the broth is neutral to litmus, then 0.5 gram of crystallized
soda is added to each 1,000 cubic centimeters. In bouillon cultures
the plague organism has a marked tendency to form longer chains,
which are composed of ten to twelve or even more small, short
bacilli. Such chains on first sight appear much like streptococci,
but a more careful examination reveals their proper structure. The
individual links of the chain are not arranged in a perfectly
straight line, but angles and bends are frequently seen.

19

The follo-\ving facts may be added to the enumeration of the
cultural peculiarities of the plague bacillus : It does not liquefy
gelatin or blood serum^, does not ferment dextrose, levulose, lactose,
or mannit, grows sparingly on potato and on milk, which latter it
does not coagulate.

In the preceding description of the morphology and of the
cultural properties of the plague bacillus no attempt has been made
to bring out all the details which have been reported in an extensive
literature, but merely to state clearly and emphasize those points
the knowledge of which is indispensable in the bacteriologic
diagnosis of plague. Staining of the plague bacilli in sections will
be referred to later.

NOSOLOGY AND CLASSIFICATION.

Bubonic plague of man is an acute, occasionally more subacute,
infectious disease, caused by a specific micro-organism, Bacillus
pestis, which generally first gains entrance through a trauma of
the skin or the mucous membranes and thence finds its way into
some of the peripheral lymph glands. In other cases it is inhaled
into the lungs, or in still others it enters directly into the general
blood circulation. These different methods of infection at once
suggest a classification into three main types — bubonic plague
proper, plague pneumonia, and plague septicaemia. Perhaps the
most prominent and most constant — certainly, even on superificial
examination, the most manifest — pathologic feature of all forms
of plague is the occurrence of hemorrhages both local at the site
or sites where the plague bacilli are colonized in great numbers,
as in the lymph glands and in the lungs, and general, subserous,
submucous, parenchymatous, and interstitial hemorrhages. The
great frequency and constancy of these hemorrhages in plague has
led to its classification as a hemorrhagic septicemia. Nothing, as
M'e expect to be able to demonstrate, could be more false than such
a definition of plague in man. It may be quite true that experi-
mental plague in certain of the lower animals is indeed generally
a hemorrhagic septicemia, but this, of course, a priori proves noth-
ing as to man. Anthrax, in some animals, is imdoubtedly a
septicemia, yet usually when contracted by man it is primarily
a local disease and frequently remains local. Diplococcus pneii-
monice, when introduced experimentally into mice, rabbits, or

20

guinea pigs, produces a septicaemia, yet in man, under natural
conditions of infection, it generally leads to a local infection of
the lungs — lobar pneumonia. We have in another previous bulletin^
called attention to the fact that all observations made on men show-
that the plague bacillus is not present at all early in the course of
the disease in the general blood circulation. Our histologic exam-
inations have further demonstrated that as a rule plague bacilli
are either found not at all in the vascular system or are present in
such very small numbers that an agonal or post-mortem invasion
suggests itself.

It appears reasonable to limit the classification "septicgemia"
to those infections in which a multiplication of the infecting micro-
organisms obviously takes place in the general blood circulation.
During the last few years a valuable diagnostic method of blojd
examination in acute infectious disease has been used quite exten-
sively. Its results, however, have led to a misrepresentation of the
character and classification of some diseases. This method is
practiced as follows: From 1 to 5 cubic centimeters of blood, for
instance, in a case of pneumonia or typhoid fever, are drawn
from a vein and introduced into a culture flask containing from
50 to 300 cubic centimeters of nutrient broth. If now a pneumono-
coccus or typhoid growth develops, it is concluded that there is in
this case a general infection of the blood. But what does it really
mean if 1 to 5 cubic centimeters of blood do contain a few bacilli
w^hich develop and multiply under the most favorable artificial
conditions, conditions entirely different from those which prevail
in the live, undiluted circulating blood? It certainly does not
mean that these same micro-organisms could and would multiply
in the circulating blood in the presence of antibodies and of many
intact leucocytes. As it w^ould be wrong to classify typhoid fever
as a septicemia, because typhoid bacilli enter the blood from the
internal lymphatics, so it is wrong to classify ordinary bubonic
plague as a septicaemia because some bacilli invade the blood from
the infected lymphatics. If we do want to take cognizance of the
frequency and of the extent of the hemorrhages in plague, we may
-define it as an infectious disease with general hemorrhagic toxaemia.

It was necessary early to enter into the discussion of this point

^ Herzog and Hare : Does Latent or Dormant Plague Exist Where the
Disease is Endemic? Bulletin B. of G. L., Biological Laboratory, No. 20, I.

21

in order to explain and justify our opposition to the classification
of plague in man as a general hemorrhagic septicaemia.

A study of the histopathology of plague suggests the following
pathologic classification into a number of groups, viz:

(1) Primary uncomplicated bubonic plague.

(3) Primary bubonic plague with secondary septico-pyemia.

(3) Primary bubonic plague with secondary plague pneumonia.

(4) Primary plague pneumonia.

(5) Primary plague pneumonia with secondary septico-pyemia.

(6) Primary plague septicemia.

This classification does not, of course, include any secondary or
tertiary complications due to micro-organisms other than the plague
bacillus. We shall be able to illustrate all of these different types
by cases investigated.

A number of writers have distinguished intestinal plague as
a special form of the disease. Wilm, for instance, believes that
the plague bacilli frequently enter the body of man through the
gastro-intestinal tract and thus lead to a type which is well charac-
terized both clinically and anatomically. Hossack says that 5 per
cent of the plague cases occurring in the Calcutta epidemic of 1900
were of the intestinal type, and that 3 per cent of those in the one
of 1896-97 were of a similar nature. Zupita reported a case
of intestinal plague, but from its description it clearly appears that
it was one of primary inguinal bubo, with primary buboes of the
second and third order in the pelvic and abdominal cavities. In
fact, we have failed to find in literature a single case which
anatomically could be clearly classified as a case of intestinal
plague. In our work special attention has been paid to this sub-
ject and every one of our cases in which a post-mortem examination
was made was carefully examined in order, if possible, to find a
primary bubo of the first order of the mesenteric or other intestinal
lymph glands. But none was encountered. It appears that up
to date the occurrence of intestinal plague in man has not been
proved beyond dispute. Even where rats have been fed on plague-
infected food, the disease is generally of the bubonic type (cervical
or submaxillary bubo) with simultaneous or secondary plague
septicaemia.

Another type of the disease which has been grouped separately,
but which generally is not accepted as a type per se, is skin or

22

cutaneous plague. In our material we have not seen an example
of this type, and it may be mentioned that cases classed as cutaneous
plague have generally only been observed clinically and not studied
post-mortem.

Musehold, in reviewing the literature on cutaneous plague, says :

The term cutaneous plague applies to those cases in which there exists
at the beginning a (primary) plague vesicle, pustule, or carbuncle without
marked involvement of the lymph glands. If in the further development of
the disease the skin lesion does not spread, but the neighboring glands
become more prominently involved, then it would be better to speak of
cutaneous and bubonic plague, or still more preferably of bubonic plague
with primary skin lesion.

The German Plague Commission among its clinical material had
fourteen cases of cutaneous plague, all of which, however, were
complicated by buboes; and the Austrian Commission likewise saw
no case of this form without typical buboes. Only Kitasato has
mentioned one case of primary plague carbuncle without buboes
but with septicsemia. From these data it would appear that a
separation into a group of those plague cases which show a marked
reaction at the cutaneous portal of entrance of the virus is hardly
justifiable and somewhat arbitrary. The extensive report of the
Indian Plague Commission does not recognize a distinct cutaneous
form of the disease.

Another type mentioned by writers is ambulatory plague or
pestis minor. While such a group is admissible from a clinical
standpoint, it has no proper place in a classification based strictly
upon the pathology of the infection. Under pestis minor are classed
those mild cases in which a swelling of some of the external
l}Tnphatics is generally observed, but in which there are no urgent
clinical symptoms, and in which, in fact, a correct diagnosis may
be arrived at only after more serious cases have made their appear-
ance. These cases properly belong to the bubonic type. Our
knowledge of them, even from a clinical standpoint, is very meager ;
from a pathologic one it is practically nil. While every case of
pestis minor is ambulatory, every case of ambulatory plague is
not necessarily one of pestis minor. Indeed we can report such a
one in which the individual died very suddenly and where on
post-mortem examination such profound plague lesions were found,
quite aside from its fatal termination, as to remove it from the
group of pestis minor.

23

THE MORBID ANATOMY AND HISTOPATHOLOGY OF PLAGUE
AS DESCRIBED IN LITERATURE.

The number of articles on plague which have appeared since
the discovery of the specific micro-organism is very considerable.
Most of the literature deals largely or exclusively with the clinical
aspect, the bacteriology, the prophylaxis, or the serumtherapy of
the infection, so that the number of contributions to its morbid
anatomy and histopathology is comparatively limited. It is surpris-
ing to find, from a lecture delivered by Virchow in 1879, how little
was then known of the pathology of the greatest scourge of the
Middle Ages.

Virchow had no opportunity personally to study cases of the disease,
and he therefore simply gives a review of the writings of the eighteenth
and nineteenth centuries, up to 1879, drawing attention to the then prev-
alent contradictory views on the pathology of plague. From these he
selected, in an admirably critical manner, those which indeed come nearest
to the correct pathology as it is now kno^vn. Virchow's plague lecture
in 1879 also contains this remarkable prophetic declaration: "To me the
similarity of anthrax and plague is so great that I consider it very possible
that we shall find an organism as the carrier of plague infection. However,
an attempt to find it has heretofore hardly been made."

Aoyama, simultaneously with the bacteriologic work which led to the
discovery of the plague bacillus, investigated the gross and microscopic
pathology of the disease. He described the swelling of the infected lymph
glands as brought about by a proliferation of their cells and he noticed the
changes found in plague in the periglandular tissue. He stated that the
spleen was always considerably enlarged, hyperemic, and soft, the kidneys
and the liver somewhat increased in size and much congested, while the
cells of these organs showed parenchymatous degeneration. The lungs are
described as unchanged. The plague bacilli were found to be present in
large numbers in the affected glands but rare or absent in the blood.

Yamagiwa's observations were made during the latter part of the plague
epidemic in Formosa in 1896. While he had access to a considerable
number of cases which he could study clinically, his pathologic material,
owing to political reasons, was limited to three post-mortem examinations.
Besides these he was able to obtain several glands extirpated inter vitam
which he included in his microscopic studies. All three of Yamagiwa's
cases were bubonic plague, one complicated by a metastatic dissemination of
the bacilli in the lungs, spleen, and liver, or, as we would now classify it, a
primary bubonic case with secondary plague septicopyemia. However, the
summary of the morbid anatomy and histopathology, as given by Yaraagiwa,
while quite correct on the whole, does not apply to all cases of plague, as
the investigation of a larger amount of material very clearly shows.

At the time of Yamagiwa's writings plague pneumonia had not
yet been described by modern writers, nor was plague septicaemia

24

well understood. So the statement that all changes, except those
of the lymph glands and the tissues of their immediate neighbor-
hood, are generally insignificant, is untenable. We have among our
own cases, some of pneumonic and septicsemic plague, in which the
changes in the glands are quite insignificant compared with those
in other organs, and of course this observation is at present not
at all new.

It is very interesting to note that in Yamagiwa's third case, where the
hemorrhagic edema and the swelling of the cervical and submental glands
was enormous, and the consequent pressure upon the trachea very great, the
latter suffered an incomplete fracture of its cartilages and became flattened
out into a scabbard-like canal. The frequency and importance of sub-
mucous and subserous hemorrhages in plague were duly emphasized by
Yamagiwa, and he calls attention to the fact that in the affected lymphatic
chain the gland nearest to the point of entrance of the bacillus is more
profoundly changed than are those farther away. However, this is not
always the case. Other changes particularly mentioned are parenchymatous
nephritis and cloudy swelling of the liver and heart muscle, acute swelling
of the spleen, and edema of the lungs. The main histologic alterations
described are degeneration of the renal epithelium with granular material
in the tubules, cloudy swelling of the liver parenchyma cells, dilatation of
splenic vessels with hemorrhagic infiltration, necrotic foci and the presence
of plague bacilli, dilatation of pulmonary vessels with interalveolar blood
extravasation, vascular dilatation, phlebitis and necrosis of the lymph
glands and of the periglandular tissue. The extensive blood extravasation
in the affected glands is explained in the following words: "The profoimd
change in the walls of the veins, the great loosening (Auflockerung) of the
substance of the vessel walls in consequence of cellular infiltration, brings
about colossal blood extravasation inside and outside of the lymph glands."

The credit of having first lucidly and correctly described a form
of plague which is now universally recognized as a separate and
important type — plague pneumonia — belongs to Childe of the
Indian Medical Service. Since his description of the pathology
of plague pneumonia has not been given the prominence it well
deserves, by several writers, it will here be quoted somewhat at
length. Of course reference to a pneumonic form of plague had
been made long before Childe's publication.

In fact, it had been well observed during the Middle Ages. During the
great plague pandemic which decimated Europe between the years 1347-1350
pneumonic plague was very prevalent and Guy de Chauliac, the physician
of Pope Clement VI, who observed the plague in Avignon, and who himself
became very sick with it, distinguished two types and wrote: "Pestis
habuit duos modos. Primuis fuit per duos menses cum febre continui
et sputo sanguinis. Et isti moriebantur infra tres dies. Segundus fuit

25

per residuum temporis cum febre etiam continua et apostematibus et
anthracibus in exterioribus, potissime in subasellis et inguinibus. Et
moriebantur infra quinque dies. Et fuit tante contagiositatis, specialiter
quae fuit cum sputo sanguinis, quod non solum morando, sed etiam
inspiciendo unus recipiebat ab alio." (Haeser: Lehrbucli der Geschichte
der Medicin, 3 Aufl., lena, 1882.)

Childe gives the following description of the first case in which he
made a post-mortem examination : "The lungs showed much general
engorgement and oedema, with sero-sanguinous frothy fluid in the bronchi,
but no pus; the usual appearances of acute bronchitis were absent. There
was one small pneumonic patch the size of a walnut, in the early second
stage, situated below the apex on the front of the right lung, and two
similar bvit smaller patches at the same part of the left lung. These patches
stood out a little from the surface, and were airless, friable, sank in water,
each was surrounded by a dark ring of engorgement, which merged into the
healthy lung, and there was recent pleurisy over the pneumonic areas.
All the other organs were examined and showed considerable engorgement,
but no special lesion was observed. The cervical, the axillary, and the
lumbar lymphatic glands were slightly enlarged. The left illiac slightly
enlarged, red, and soft; all the other glands, including the bronchial,
looked absolutely normal. Cultures made from the pneumonic lungs and
spleen developed plague bacilli." Childe, in the same article, reports the
clinical features of two cases of pneumonic plague — those of a physician
and of his nurse — and then says:

"This form of plague is highly infectious, and probably has a large share
in the spread of the disease, for in these cases the patient's . sputum is
practically a pure culture of the plague bacillus, and, as there is reason
to believe that many of the cases are not recognized as plague at all,
precautions are not taken by the patient's friends and the dangerous nature
of the disease is not appreciated. I have no means of knowing how frequent
this variety of plague has been in the present epidemic, but there is some
evidence to show that a considerable number of cases have occurred.
* * * With regard to the literature on this subject, I have not been
able to find a published description of this variety of plague, but an allusion
is made in the accounts of the Pali epidemic of 1836, and it is stated that
the Astrakhan outbreak of 1877 was first regarded as croupous pneumonia
or as typhus complicated by pneumonia. From the reports on the Hong-
kong epidemic it appears that plague pneumonia did not occur there.
There is just this to add: The usual definition of plague in works of
medicine is: 'A specific fever, attended by bubo of the inguinal or other
gland,' but it seems that such a form of words does not include all varieties
of the disease."

In a later contribution on the pathology of plague Childe also takes
up that of the common bubonic type, and states that the glandular
lesion is chiefly at the site of the bubo and there are but slight lesions
of the lymphatic glands throughout the body, but there are foimd
engorgement or petechise, or hemorrhages in nearly all viscera, notably
in the alimentary canal, especially the stomach and large intestine,

26

the kidneys, and bladder, the pericardium, pleura, and peritoneum, and
with enlargement of the liver and spleen. In the septicsemic form there
is general involvement of nearly all the lymphatic glands and lesions
in the other organs similar to those found in the bubonic form. No bubo
of the mesenteric glands was ever found. These glands were always
examined, and, though changes might be found in them, they were always
less marked and less distinct than plague glands found in other parts
of the body. In short, there was no necropsy, which went to show that
the plague bacillus had reached the stomach or intestines — for example,
in food — and thence infected the mesenteric glands.

In his later contribution Childe describes the pneumonic form of plague
as follows:

"In this form of plague the only marked evidences of disease are found
in the lungs. The lymphatic glands and other organs are scarcely affected
at all. In the lungs there was general engorgement, with considerable
oedema, a reddened condition of the mucous membrane of the bronchi,
but no marked evidences of bronchitis, and frothy watery fluid, some-
times blood stained, could be squeezed from the bronchi. (Pus in the
bronchial tubes was only found on one occasion.) A number of pneumonic
patches were found scattered through the lungs, varying in size from
a pea to an egg. They were light pink or red gray in color, solid, airless,
and sank in water. They were rounded in shape, and usually separated
by a distinct ring of engorgement from the crepitant lung around. Some,
instead of being pink, were of a deep blood color throughout and less
solid, and some of these had a small, greyish, more solid center. Those
of the patches which were situated on the surface of the lung were
prominent, and projected distinctly from the surface whilst the pleura
over them was roughened, and showed signs of early inflammation. These
patches had, in fact, the appearance of the first and second stages of
lobular pneumonia, but no patches were found which had passed on to
the third stage of softening and breaking dowai. In a few cases larger
masses of pneumonic lung tlian these were found and once about half
the lower lung was found in this condition. Petechial hemorrhages were
usually found on the surface of the lung; the bronchial glands were either
enlarged, swollen, (edematous, soft, and distinctly engorged, or else they
were small, and of the usual appearance, perhaps a little engorged. The
remaining lymphatic glands throughout the body showed none of the
appearances of either the bubonic or septica;mic form of plague; most
of them looked absolutely normal, and the only noticeable change was
that the axillary and sometimes the cervical chains were a little engorged."

Childe found large hemorrhages absent in plague pneumonia, but the
usual subserous or submucous petechise and ecchymoses were present.
This author describes the microscopy of the pneumonic form as follows:

"A section of lung tissue, apart from a pneumonic area, shows great
engorgement of all large blood vessels, and of the alveolar capillaries as
well, and patches of hemorrhage into the alveoli around these engorged
vessels are seen scattered about. In a pneumonic area three zones can
be made out. At the circumference therQ is intense engorgement of

27

all vessels including alveolar capillaries, the alveoli are full of blood
and the hemorrhage is so intense that many of the alveolar septa are
broken down, entirely absent, or represented by mere shreds. Within
the circumference is seen a zone in which the alveoli are intact and are
completely filled with well-stained cells, so that there is no interval
between the alveolar wall and their contents, and in the center is one
universal mass of similar cells, and the cellular infiltration is so extreme
that the walls of the alveoli are scarcely visible. Such is the general
arrangement of the pneumonic patch, although there may be alveolar
hemorrhage in parts of either the middle or central zone. Under a higher
power the alveoli of the circumference are seen to be completely filled
with blood corpuscles, and a little fibrin or none at all, whilst the dense
central mass of cells consist of catarrhal epithelium and leucocytes with
some granular debris. Thus the pneumonic area has the appearance of
very extreme lobular or catarrhal pneumonia. The walls of the bronchial
tubes, as well as the large veins, show great engorgement and there are
hemorrhages into the vein walls. Blood and catarrhal cells may be seen
in the finer bronchi, but the bronchial mucous membrane is scarcely
altered, there being at most a little cellular proliferation. There are
the appearances of acute pleurisy over those pneumonic areas which
project upon the surface of the lung, with hemorrhages beneath the pleura.
The bronchial glands show engorgement of blood vessels, but in some
cases these conditions are only slightly marked and the glands looked
nearly normal. * * *

"In cases of plague pneumonia the bacilli were seen in abundance in
the pneumonic areas; they could be found in pi'ofusion amongst the
catarrhal epithelial cells and leucocytes which filled the alveoli and
terminal bronchioles, as well as among the blood corpuscles of the alveoli
into which hemorrhages had occurred."

Childe also describes a case of plague septicaemia with secondary deposits
in the liver, which in this particular instance was most peculiar; it was
slightly enlarged and congested, as in the early nutmeg condition, and was
stuffed throughout with small, yellow, rounded masses, varying in size
from a pin's head to a pea. They were rather soft and friable, but not
fluid, and there was no area of engorgement around them. They were found
both on the surface and throughout the whole substance of the liver.
They looked like necrotic foci and microscopically proved to consist of
dense masses of plague bacilli with necrotic cells surrounding them.

It may here be mentioned that Bazaroff, working under the direction
of Roux, first produced plague pneumonia experimentally in animals by
introducing plague bacilli in their nasal cavities. The disease developed
by experiments is described as a lobular or confluent broncho-pneumonia
with secondary general septiciBmia.

The German Commission distinguishes three types of plague: Bubonic
plague, plague pustule of the skin, and plague pneumonia. Whether an
intestinal form of plague exists the Commission is unable to decide; it
did not encounter a case in the human material examined, though it
succeeded in producing intestinal plague in rats and monkeys by feeding

28

them infected food. The Commission does not believe in the existence
of a true primary plague septicaemia and its report states with reference
to this subject:

"Primary plague septicaemia probably does not exist. At least our own
Commission as well as the Austrian one, and other investigators, have
found on post-mortem examination, in such cases in which the portal of
entrance of the virus could not be ascertained, small hemorrhagic glandular
foci, or a focus in the lung. These had in consequence of the indifference
of the patients or in consequence of their occult location, escaped notice
during life. Hence plague septicaemia is not a special type of the disease,
but the generalization of a primarily local process. That it may then
again lead to other secondary internal foci we have demonstrated in a
case of plague meningitis."

Septicopj-emic processes with pus metastasis, the commission
believes to be due to a mixed infection, as is also the case in
purulent abscess formation of the plague bubo. From this condi-
tion the commission separates a puriform softening of the bubo
without abscess formation, which may occur in pure plague infection
without the presence of other micro-organisms. The pathologic
anatomy is described as follows :

The bubo is anatomically a larger or smaller tumor, which contains
one or more enlarged lymph glands; these are rarely greater than a
pigeon's egg. They are united into one mass by either oedematous or
hemorrhagic connective tissue. The glands and the surrounding tissue
show all degrees of inflammation, from simple medullary swelling to oedema-
tous infiltration, bloody infraction, suppuration, and complete necrosis,
according to the intensity of the process, the duration of the disease, and
the single or multiple microbic infection. As is the case with the
periglandular tissue, the neighboring fascia, the areolar tissue, the muscles,
the sheath of the vessels and the nerves may likewise be included in the
oedematous gelatinous or hemorrhagic infiltration; these structures may,
as it were, become parts of the bubo. It is not so rare to find a bubo which
extends from the inguinal glands to the cysterna chyli, from a cubital gland
into the axillary space up to the vena subclavia or from the angle of the
maxillae deep into the thoracic cavity. In such extensive cases the periph-
eral glands show a milder, the more central ones a more profound degree
of inflammation and destruction; while the younger stage of the process is
present in the latter, the older one in the former. The anatomical findings
in the plague-infected lung can be described with few words. In the lobular
form, we generally have quite an extensive process with its favorite seat
in the lower lobe. This lobular type of pneumonia is characterized by a
peculiar mixture of the different stages of hepatization and by an accom-
panying serous catarrh. In the hybrid types in which old tubercular foci
and fresh plague infiammatory processes are mixed, the picture becomes
still more varied. Twice we saw in croupous foci, necrosis and hemorrhagic
infiltration of the center to such an extent that expulsion of larger masses

29

of lung tissue and pi'ofuse hemorrhages might have occurred at any
moment. The bronchial glands, in some cases of plague pneumonia,
appeared like the external primary buboes, while in other ones, more
extensive changes were lacking. Besides the primary lesion one regularly
finds in plague cases, even in those which have died in the second or third
week from complicating affections, blood extravasations into the various
internal organs. Rarely have such hemorrhages taken place into the skin,
the subcutaneous connective tissue, or into the muscles. However, petechise
in the mucosa of the intestinal tract, frequently confined to the fundus
of the stomach and to the cecum, are often found. These hemorrhages
usually vary from the size of a mere point to that of a lentil, or sometimes
they may even be larger. They often have become confluent stripes, and
appear as such on the mucosal folds. In a few cases such punctiform
or linear hemorrhages are seen from the pharynx to the anus. Where old
ulcerative processes are present the hemorrhages frequently appear around
such lesions. One finds petechiae regularly in the pelvis of the kidneys,
more rarely in the renal capsules, in the gall bladder, in the serous
membranes of the heart, the lungs, the liver, etc. The lungs, the testicles,
the sheath of the nerves, the dura, the uterine mucosa, the placenta, are
in some cases the seat of more extensive hemorrhages, even if far distant
from the seat of the primary bubo.

All these hemorrhages are not the direct effect of the bacteria, but more
probably the consequence of intoxication. In proof of this view the Com-
mission reports that it obtained three fetvises from plague patients. All
three presented numerous hemorrhages but were found absolutely germ
free. The Commission further states that it generally found marked
parenchymatous degeneration in the internal organs, generally enlargement
of the spleen and swelling and hyperemia of the lymph glands aside from
those affected by profound hemorrhagic infiltration.

The German commission does not report any microscopic exam-
ination of tissues from plague cases.

Albrecht and Gohn,^ of the Austrian Plague Commission, have introduced
the terms primary and secondary buboes. Primary buboes, according to
them, are those which are formed by the introduction and the extension
of the micro-organisms along the lymph channels, while a secondary bubo
is always the result of the propagation of the virus by the blood current.
The chief form of plague is denominated by them "septicsemic hemorrhagic."
It is characterized by a primary bubo, located most frequently in the
inguinal, axillary and cervical regions, about which there occurs a hemor-
rhagic oedema, and at greater distance hemorrhages into the organs. The
spleen is swollen, the general lymph glands are enlarged, and the paren-
chymatous organs show degenerative changes. The primary bubo may be
entirely lacking, the swelling of the lymph glands may be inconspicous,
and the hemorrhage may be the only pronounced sign.

^Albrecht and Gohn's original report has not been accessible, and we
therefore quote mostly from Musehold, Flexner, and others who have
freely referred to the work of the Austrian commission.

30

A second form of the pest which they describe is the septicopyemic.
In it embolic foci are present in the lungs, the liver, and the kidneys. A
third one is the primary pest pneumonia, which is a confluent lobular
pneumonic process, usually attended with, noticeable lymphatic enlarge-
ment. The common portal of entrance of the bacilli is the skin, but only
exceptionally can the precise point of infection be discovered, the demon-
stration of the place and the mode being indicated by the location of the
primary bubo. A single instance of purulent meningitis, due to the pest
bacillus, was encountered by the Austrian Commission. The invasion of
the blood takes place always from the primary bubo or from the lungs,
as a primary blood infection does not exist. The primary bubo may be
so small that it cannot be discovered clinically and is found anatomically
only after careful and prolonged search. In foudroyante cases the formation
of a bubo may fail altogether. The primary bubo is distinguished by
destruction of the lymphatic parenchyma, necroses, and hemorrhages, and
(in the case of mixed pj'ogenic infections) by suppuration. A similar
condition is fovmd in the surrounding cellular tissue. Bacilli are present
in great numbers. The secondary buboes show, on the other hand, uniform
hyperemia, occasionally hemorrhages, and, in more protracted cases,
medullary swelling. The primary buboes of the second order approach
one or the other type, depending upon their distance from the gland
primarily affected. The multiple hemorrhages are not the result of the
action of toxines elaborated at a distance, but are caused directly by bacilli
which may always be found in the neighborhood. Parenchymatous and
fatty degeneration of the heart, the liver, and the kidneys occur commonly.
Splenic tumor is a constant occurrence. The spleen shows marked changes.
The pulp is distended with blood and contains many poly-morpho-nuclear
cells. The follicles are but little altered, but the trabeculse are swollen and
homogeneous. In some instances the endothelial cells of the pulp have
proliferated and desquamated. When very great numbers of bacilli are
present miliary necroses may occur. The bacilli are very abundant in the
pulp, more scanty in the follicles; sometimes they may be contained within
cells. In the pysemic form of the disease foci are formd in the liver, the
limgs, the kidneys, the spleen and the musculature. In about one-third
of all the cases of plague secondary pyococcal infection has taken place.

The primary pneumonia appears in the form of a lobular consolidation,
which, when foci are numerous and confluent, may produce lobar solidifica-
tion. Bronchitis is present. The bronchial lymphatic glands present
appearances of primary, the others of secondary buboes. In addition to
the primary, two other forms of pest pneumonia are recognized, one
metastatic, which appears as multiple and larger foci, seated beneath
the pleura, the other as an aspiration pneumonia, from the aspiration of
infected material derived from buccal buboes. In plague pneumonia one
generally sees shining through the lungs, fine, yellow and red markings
or spots, which are produced by yellowish points or stripes on a red back-
ground. The picture resembles the one presented by plague lymph glands
rich in bacilli. In the lungs this appearance is produced by enormous
masses of bacilli contained in the alveoli. The cut surface shows a picture

31

similar to that seen on the pleural surface; much viscid exudate can be
scraped from the surface. The plague foci in the lungs are surrounded by
a hemorrhagic ring in an oedematous area. The alveolar septa are broad-
ened. Microscopically they consist of a tissue which stains well with eosin,
and which contains a few cells or cell nuclei or red blood corpuscles.
The finer changes in the lymph glands, according to Albrecht and Gohn,
consist in necrosis of the vessel walls and in a very peculiar coagulation of
blood constituents. The more resistant vessels are generally enlarged,
their walls somewhat thickened. They are either uniformly thickened and
homogeneous or more frequently composed of solid bands of fibers which
stain deeply with eosin. In the interior of a vessel with such changed
walls, one finds a similar reticulum, sometimes consisting of fine filaments,
sometimes containing irregular masses or lumps. Threads penetrating
the vessel walls are in connection with the threads in the interior. The
picture reminds Albrecht and Gohn of the coagulation necrosis observed
in the epithelial layers of a diphtheritic membrane. Fibrin, however, is
either not found at all or else sparingly.

Wysokowitz and Zabolotny, members of the Russian Plague Commission,
studied the disease in Bombay; they made twenty-seven autopsies and
most of their cases were those of bubonic plague. Six were of the primary
plague pneumonic form. In the bubonic cases they also found all the
other glands more or less swollen; however, these were less afi^ected than
the primary bubo, which was generally found to be very hemorrhagic.
Plague pneumonia is classified by them as a bronchopneumonia, with
a tendency of the foci to become confluent in the more protracted cases.
A whole lobe was never found involved in the pneumonic process. Hemor-
rhages in the gastric and intestinal mucosa were present in many cases
of all types, and the mesenteric glands were usually enlarged; in one
case the liver showed necrotic foci. The Russian authors, neither in their
clinical nor in their post-mortem researches, saw a case which would suggest
the intestines as the portal of entrance of the plague virus.

The Anglo-Indian Plague Commission, whose medical members
were Fraser and Wright, has published in five volumes the most
extensive report on the great modern plague epidemic of India.
It divides plague into four types, namely, (1) bubonic, (2) sep-
ticsemic, (3) pneumonic, and (4) pestis minor or ambulans, and
elaborates upon the classification as follows (Vol. V., p. 53) :

( 1 ) Plague, in its most typical variety, takes the form of bubonic
plague. In this form of plague the bacteria are carried by the lymph
stream into the lymphatic glands, in particular into the lymphatic glands
of the groin and the axilla — less frequently into those of the neck. The
bacteria multiply there, and excite a considerable amount of swelling
and inflammation, which manifest themselves in the form of a bubo.
The development of this bubo is often associated with severe pain.
Following closely upon — more rarely preceding — -the development of the
bubo, constitutional symptoms set in. They consist in malaise, headache.

32

and fever, frequently accompanied by collapse and vomiting. When the
bacteria have grown through the meshes of the lymphatic filter, they are
carried on by the lymph stream into the blood. The disease then becomes
septicsemic.

(2) Distinguishable clinically though, from the point of view of the
pathologist, not sharply marked off from the secondary plague septi-
caemias just described, are the cases of plague commonly spoken of as
septicsemic, in contradistinction to bubonic cases. These are the cases
where, owing to the more rapid passage of bacteria through the lymphatic
filter, and possibly to a greater production of bacterial poisons, the
constitutional symptoms precede and overshadow the local symptoms, the
disease being in most cases rapidly fatal.

(3) In the third form of plague, first bacteriologically established by
Captain Childe, I. M. S., plague bacilli invade the lungs and give rise
to pneumonia, death occurring in most cases within a few days after
the patient has been attacked. Owing to the absence of buboes, the
pneumonic form is often classed, along with the septicsemic form, in the
category of nonbubonic plague.

(4) In addition to the three main types of plague which have been
described above, an abortive form of bubonic plague comes under observa-
tion. This is technically known as pestis minor, or pestis ambulans. It
can not be doubted that in these abortive bubonic cases the bacteria are,
as in the case of ordinary bubonic plague, carried to the lymphatic glands,
but they are held back there, the disease stopping short of the septicsemic
stage. In correspondence with this the constitutional symptoms are very
light. Indeed in certain cases not only the constitutional, but also the
local symptoms may be so slight as to be, except for their pathological
interest, almost undeserving of attention. Such cases appear to be ex-
tremely common among persons who have been much exposed to the
infection of plague and are characterized by sensations of numbness and
tingling, or by neuralgic pains, which in many cases are associated with
the development of spotty glands in the armpit and the groins. We may,
however, remark here that the w^hole question of pestis minor urgently
requires to be more fully elucidated.

From very extensive data the Indian commission has compiled
the following summary of the pathology of plague :

Caste and other prejudices of the natives, which were consistently
respected, have limited the number of post-mortem examinations relatively
to the large mortality from the plague in India. Descriptions of the
post-mortem appearances have, however, been laid before us, which together
amount to a considerable total, and are sufficient to clearly establish the
more important pathological features of plague. References may specially
be made to the reports of Dr. Choksy; Captain Childe, I. M. S.; Dr. Dyson
and Captain Calvert, I. M. S.; Captain Thomas, I. M. S., and Captain
Leuman, I. M. S., and to the evidence of several of these gentlemen and
also of Captain Wilkinson, I. M. S., Major Evans, I. M. S.. and Captain
Elphick, I. M. S.

. 33

Pestis minor. — Death from Pestis minor probably never occurs, at any
rate, no description of the pathology of plague deals with this type.

Pestis major, lymphatic si/stem. — (a) Buhoes. — The appearance of the
buboes was characteristic. As we have already stated, they varied much
in size and to a less extent in number. For the most part they consisted
of enlarged lymphatic glands surrounded by extravasated blood and serum,
which in many instances extended widely and deeply into the neighboring
areolar tissue, and often penetrated into the substance of the muscles.
Sometimes only one gland was included in a bubo, but more frequently
there were several, and at times an external bubo was directly connected
with one involving deeper seated neighboring glands, and when a femoral
bubo extended inwards so as to be continuous with one involving the
iliac glands. The swollen glands and the surrounding tissues were often
"matted together — so that it was difficult when once cut into it (the
bubo) to be quite sure which was gland and which was surrounding
tissue." The affected glands were round or oval in shape, and they
varied in size from that of a pea to that of a walnut. On section, they
were seen to be much engorged with blood, of a light red or deep purple
color, and of firm consistence in some cases, but soft and almost diffluent
in others. When the bubo was in the groin, the limb of the same side
was usually swollen and cedematous; when in the axilla, the serous
effusion and hemorrhagic exudation was sometimes so great as to form
a swelling involving the whole axilla and extending down the inner aspect
of the arm to the elbow, and do-\vn the side of the chest nearly to the
lowest ribs; and when in the neck a large swelling frequently resulted,
which pressed upon the larynx, trachea and cervical nerves and blood
vessels, and thus produced the dyspnoea which was so conspicuous a
symptom in those cases. As buboes in the groin and axilla frequently
pressed upon or surrounded the large blood vessels in these regions,
the oedema in the corresponding limbs is readily accounted for.

It has been pointed out by Dr. Childe that in axillary buboes and
occasionally in chains of enlarged glands along the course of the iliac
artery and veins, the extravasated blood may be continuous with blood in
the interior of the veins, thus forming "a direct path for the passage of
the plague bacillus from the gland to the lumen of the vein, and so into
the general circulation."

In a few cases of Pestis major, no pathological changes were found in
other lymphatic glands than those in connection with which buboes had
formed; but in most cases, many other glands, and especially the internal
glands, were affected. The changes in them, however, were relatively slight,
for they consisted only of enlargement, and of either moderate or great
congestion, a section of the gland in the latter instance showing much
engorgement with dark blood. In individual cases, many or few of the
glands were affected; but indeed no lymphatic gland, whether internal or
external, seemed to escape involvement, for these changes were observed
in various groupings, in the bronchial, mesenteric, peritoneal, iliac, lumbar,
trochlear, popliteal, and other glands.

25483 3

34

Lymphatic vessels. — In most cases, the lymphatic vessels showed no
pathological change, and only in a few were they observed to be congested
and swollen, and that only close to the bubo.

Alimentary system. — The pharynx and the tonsils were greatly congested,
the latter being enlarged and occasionally in a state of follicular inflamma-
tion. This congestion usually extended down the oesophagus, and in some
cases hemorrhages were found in its walls. The stomach was almost
invariably engorged with blood, and both minute and considerable hemor-
rhages were present in the mucous membrane. These hemorrhages have
been classified by Captain James, I. M. S., as follows:

"A mild form in which, on holding the coats of the stomach up to the
light, the course of the^ smaller vessels was found to be picked out by
extravasations which also formed small arborescent patches on the mucous
surface, or perhaps only reddened the edges of the rugse.

"A severe form in which there were more or less extensive patches of
hemorrhage into the submucous tissues or even into the stomach cavity.

"Distinct numerous petechise with definite circular outlines and varying
in size from that of a pin's head to that of a split pea. In one case the
petechife were very numerous and covered nearly the whole of the mucous
surface of the stomach. The appearance was so striking that it reminded
one of the rash seen on the skin in a severe case of purpura."

Similar appearances have been observed in the intestines. Congestions
and hemorrhagic extravasations were most frequently seen in the large
intestine and rectum, and less frequently in the small intestines. Occasion-
ally Peyer's patches and the solitary follicles were observed to be swollen.
The liver and the spleen were enlarged, the latter being sometimes two
or three times the ordinary size. Petechise were frequently present on the
surface of the liver, and its substance was engorged with dark blood, and
was soft and friable, indicating degenerative change. The spleen also was
generally in a state of acute degeneration, soft and pulpy, and in some
cases almost diffluent. On section, it was brick red or deep chocolate
bro\\'n and always greatly engorged. The gall bladder usually contained
bile, and occasionally there were petechise on its mucous lining. The
kidneys were also much enlarged and engorged with blood, and presented
the characteristics of acute parenchymatous degeneration. Minute hemor-
rhages were sometimes observed on the surface, and petechise and coagulated
blood in the pelvis and calices. Extensive hemorrhagic extravasation has
also been found outside the kidneys, which were then found "lying in a
bed of blood." The ureters and bladder were engorged, and petechise were
frequently present on their inner surfaces. Besides engorgement, no
important change was observed in the supra-renal capsules or thyroid
gland, and the genital organs presented a normal appearance. The peri-
toneum was considerably engorged, but, above all, hemorrhages, often of
large size, were found in many parts, as in the mesentery, in the retro-
peritoneal connective tissue, on the luider surface of the diaphragm, and
over the spleen, liver, kidneys, and intestines.

Circulatory system. — The blood was dark and fluid, and gave the impres-
sion that it did not coagulate well. The pericardium generally contained

35

more fluid than usual, which was sometimes blood stained; and minute
hemorrhages were found in both its vesical and parietal portions. The
myocardium was generally soft with many muscle fibers undergoing granulo-
fatty degeneration : and the right ventricle was always dilated while in
many cases there was also dilation of the other cavities of the heart. The
walls of the larger vessels appeared normal, but those of the veins were
engorged, and minute and large hemorrhages were frequently observed
beneath the inner coat. Dr. Childe found that when a large vein was
included in a bubo, hemorrhage into its walls was constantly seen, so that
the extravasated blood in the gland itself, in the areolar tissue outside,
and in the walls of the vein was continuous.

Respiratory system. — The larynx was in all cases affected and in a few
instances there was hemorrhage beneath its surface. In cases of cervical
bubo, (Edematous swelling involved the soft structures of the larynx and
the aryteno-epiglottidian folds. The bronchial tubes were also congested
and swollen, and in many cases contained blood-tinged frothy fluid;
but the trachea was merely congested. The lungs were engorged with blood
and with serous fluid; occasionally small hemorrhages were found in the
lung svibstance, and when the lungs were cut into much sero-sanguinous
fluid escaped. When pneumonia or broncho-pneumonia had occurred as a
complication, the pathological changes produced by these diseases were also
present. The pleural cavity contained blood-stained or clear fluid. Sub-
pleural hemorrhages, sometimes of large extent, were found on the parietal,
visceral and diaphragmetic pleura and occasionally there was evidence of
fibrinous inflammation. Hemorrhages were sometimes present in the
anterior and posterior mediastina.

1^'ervous system. — -The dura and pia mater of the brain, as well as the
coverings of the spinal cord, were congested, and in a few instances extra-
vasations of the blood were found on the dura mater. The brain substance
and spinal cord generally presented a healthy appearance; but occasionally
congestions and oedema were present, which involved likewise the choroid
plexuses. No pathological change has been observed in the nerve trunks.

Bones, joints. — It has further been noted that the marrow of the long
bones is red and congested as in other infectious fevers, and that evidence
of an infective inflammation is found in the fringe-like processes of the
synovial membrane of the knee joint.

Intense or septiccemic type of plague. — In those cases in which the plague
virus or toxin is in the patient widespread from the beginning of the
illness, so as early to produce a general poisoning, whether septicemic
or toxsemic, the pathological changes, an might be expected, are much the
same as in the more severe cases of Pest is major. Some observers, however,
believe that pathological difl"erences occur to distinguish this form of
plague, and to serve, along with the symptoms, as a justification for the
establishment of a so-called septicaemic type of the disease. They consist
of the absence of buboes having the characters above described, and of a
widespread invoh'ement of glands, with ' distinctive changes in several of
them. Although the lymphatic glands are always aflFected, in place of the
affection consisting of one or, more rarely, of several groups of glands

36

being enlarged and surrounded with sero-sanguineous extravasation, while
the other glands are either normal or merely enlarged or congested, in
this, the so-called septicsemic form, the affection of the glands shows itself
as a general involvement of all, or nearly all, of the lymphatic glands of
the body, although in many instances the affected glands were chiefly
those of the mesentery. In no case, however, did the involvement proceed
to the formation of the characteristic plague buboes, but only to a moderate
degree of change, practically restricted to the glands themselves, but still
displaying in several of them certain distinctive features. These were
moderate enlargement and cedema without much congestion, the glands
being pink in color, firm and rounded, and with a soft interior, often
possessing here and there small areas of softening surrounded by firm
substance. Several of the affected glands may be thus modified, while
others of them are merely enlarged and engorged with blood, thus resembling
the less affected glands of ordinary Pestis major. Excepting the lymphatic
glands, the parts that were affected showed essentially the same pathological
changes as in the biibonic variety of Pestis major, but usually the number
of parts affected was smaller and the degree of change in them was
less.

Pestis pneumonica or pulmonalis, or primary plague pneumonia. — Inflam-
mation of the lungs occurs, as already stated, with considerable frequency
during the course of the plague, and it then becomes a serious complication.
It also occurs so early in the disease as to justify the belief that the
plague virus had affected the lungs either primarily or coincidentally
with the more general affection of the body, thus constituting a form of
plague which is distinguished as primary pneumonic plague. When con-
trasted with those occurring in Pestis major, the pathological changes
elsewhere than in the lungs are less intense. While those in the lungs
are more intense. The lymphatic glands are only slightly affected, and
external buboes having the characteristics seen in Pestis major are seldom,
if ever, encountered. Congestion and enlargement of organs and even
hemorrhage in mucous and serovis membranes may be present, but they
do not assume the proportions attained in Pestis major. On the other
.hand, the lungs are conspicuously affected. The whole substance is en-
gorged, the large as well as the small blood vessels being distended; and
hemorrhagic zones are seen scattered throughout the lungs, filling the
alveoli and often breaking do^Ti their walls. Within the hemorrhagic
zones are areas in which the alveoli are completely filled with leucocytes,
epithelial cells and granular debris, constituting, with the surrounding
zones of hemorrhage, blood-congested areas of catarrhal pneumonia. In
these areas, as well as in the fluid matter contained in the trachea and
bronchi, plague bacilli are abundantly present. Greyish necrotic patches
have also been found containing large numbers of plague bacilli. The
bronchi are engorged with blood, and catarrhal cells are found in their
terminations. Over affected areas at the surface of the lungs, the pleura
may be acutely inflamed. In most cases, the bronchial glands were con-
gested, and there was a little hemorrhage into the gland substance; but
in some cases, their appearance was normal.

37

While, liowever, a catarrhal inflammation of lobular distribution has
most frequently been regarded as the characteristic type of primary plague
pneumonia, several observers have denied its existence, and have asserted
that croupous (lobar) pneumonia is the form which most frequently
occurs. Major Evans, I. M. S., and Captain Elphick considered that all
cases of typical plague pneumonia come under the latter category, and
Major Jones expresses the opinion that "lobar pneumonia is common."
Major Evans stated that the pneumonia is distributed in small patches,
constituting lobular areas, only when the inflammation has not advanced
far; but that it is lobular to the extent of involving a whole lobe or the
greater part of a lobe when the lung inflammation has advanced further.
Captain Elphick, I. M. S., described several autopsies in which individual
lobes or even an entire lung were consolidated, and he stated that "every
case of pneumonic plague examined showed lobar condensation." It may
further be stated that in many cases only slight changes were found in the
bronchi. It is therefore possible that the pneumonia is lobular in patients
who have died at an early stage of the disease, and lobar in those who have
survived to a later period; or, otherwise, that lobar pneumonia occurs
when the toxin is most virulent and most widely distributed throughout
the lung, and lobular pneumonia when it is less virulent and less widely
diffused.

The microscopic examination has mainly shown general dilatation and
engorgement of the veins and smaller blood vessels and numerous capillary
and larger hemorrhages in almost every structure and organ of the body.

Indian Plague Commission's summary of pathological conditions. — "The
distinctive pathological changes produced by the virus of plague would
therefore appear to consist of universal dilation and engorgement of veins
and smaller blood vessels, with hemorrhages, both minute and of large
amount, in nearly every part of the body, and of enlargement of the
lymphatic glands, with oedema and hemorrhage in the surrounding tissues,
generally mainly implicating the external glands, but occurring likewise
throughout the body and involving in a series of cases the entire system
of lymphatic glands. In the lymphatic glands, the characteristic conditions
are largely explainable by vascular changes, and even in the pneumonia of
plasrue. vascular dilatations and hemorrhagic extravasations give a special
character to the lung inflammation. In no other infective disease are these
features represented, but it is of some interest to note that the vascular
changes, and especially the prevailing and characteristic tendency to
extravasation of blood in almost every part of the body, are closely repro-
duced in toxaemia caused by the organic poison secreted by the venom
glands of several species of serpents such as the black snake {Pseudechis
porphyriacus) of Australia."

Flexner, who examined six cases of plague in San Francisco, besides
giving a summary of the morbid anatomy, reports more fully on the
microscopic changes of the lymph-glands and of the spleen. He states
that in the primary bubo the separation into the medulla and cortex has
been effaced, that masses of lymphoid cells still exist but that they do not
compose typical structures. Remains of cell forms, nuclear fragments,

38

shadows of red blood corpuscles, and plugs of finely granular structure
are seen filling spaces which suggest preformed vessels. Hemorrhages
exist in the medullary and cortical parts. The bloodvessels are commonly
thrombosed. The thrombi consist of cells, both mononuclear and polynu-
clear and fibrin. The walls of the smaller vessels often are hyaline and
structureless. Fibrin stain shows a fine network of fibrin about the
vascular walls, occurring partly within the lumen, partly within the wall,
and partly beyond in the perivascular tissues. Larger vessels show instead
of the fibrinoid transformation of their walls, destructive and infiltrative
changes. The intimal and medial coats contain an increase of cells and
many cell fragments. This infiltrative condition is especially marked in
the midddle coat. That many of these cells are polymorphonuclear is
shown by the bizarre forms and the staining properties of the nuclei. The
periglandular structures are extensively infiltrated and usually show
necrosis as well. The infiltration is partly cellular, partly fluid, along
with which fibrin is perhaps invariably present. The oedema and fibrin
are found chiefly in the coarse fibrous septa of the adipose tissue; the
cells occupj- the meshes of the fat cells. Bacilli are abundant in count-
less numbers within the swollen glands and in the periglandular tissues.
They occur in continuous growth throughout the glands, occupying every
available space; they completely occlude many blood vessels or, mixed
with definite thrombi, compose a considerable part of the plugs. Moreover
the walls of the blood vessels contain masses of bacilli having grown
within the vasa vasorum and the lymph spaces. The adventitial coats of
veins and arteries are especially rich in such growth of bacilli. In the
primary buboes of the second order the changes are all much less advanced
and marked.

In a case of tonsilar infection changes similar to those described in
the primary bubo of the first order were observed. The presence of cells
resembling plasma cells is mentioned and many of these were observed to
be phagocytic. The spleen, in Flexner's six cases, was found moderately
enlarged, somewhat diminished in consistencv, color deeper than normal.
The pulp is described by the author as swollen, the swelling being the
result of cellular proliferation, cellular infiltration, and cedema. The
proliferation especially affects cells closely united with the veins and
surrounding the trabecular. These cells have reticulated nuclei, placed
excentrically, and a fair allotment of protoplasm, taking the blue thionin
stain. The cells are often polyhedral rather than roimd. They have a
close affinity to plasma cells. The lymphoid cells are increased, but to a
less extent than the cells just described. The vascular and other spaces
in the pulp contain an increased number of red corpuscles. In the same
spaces occur large cells of two kinds. One is a giant cell with single,
lightly staining, reticulated nucleus and a moderate amount of protoplasm,
and resembling the large, mononuclear, marrow cell with which it is
probably identical; it is not phagocytic. The other is a much smaller
cell, three to four times as large as the marrow cells and is highly
phagocytic.

39

Tlie macrophages eiiglobe white cells — both mononuclear and poly-
nuclear — but rarely red blood corpuscles. They occur at times within the
larger veins, especially such as exhibit the subintimal cellular proliferation
to be described. The polymorphonuclear cells in the pulp exhibit great
variation in form and many would seem to have been in a state of active
migration when the tissue was fixed. They show great variety of form,
such as is seen in actively motile cells, and they would seem to be
moving in numbers in the pulp. Fibrin is found among the pulp cells
and in the fluid, and many bacilli are present.

The Malpighian bodies are increased in size, this being due to the
multiplication of the lymphoid cells, and, to smaller extent, of epithelioid
cells. The latter do not occupy the centers of the nodes, but are few in
numbers and placed peripherally. Their nuclei are large and vesicular,
rarely a cell contains two nuclei. Degeneration of cells is uncommon, very
few fragmented ones being visible. Rarely small islands of fibrin are
present in the nodules.

The blood vessels show two kinds of change. The arteries, chiefly those
of the Malpighian bodies, have hyaline walls; the veins of all sizes fre-
quently show subintimal cellular proliferation. The cells in the intima
are mononuclear and more rarely poljniuclear elements that form a
continuous, although not uniform, investment or appear as isolated pro-
jections into the lumen of the vessel. Above these cells the displaced
endothelial cells can usually be detected. Bacilli are very numerous,
especially in the pulp. They also completely occlude small blood vessels,
and within the trabeculte, probably lymphatics. However, since the richest
growths of bacilli are often unassociated with reactions, it is highly
probable that they may have taken place post-mortem.

Calmette and Salimbeni made observations on plague during the last
Oporto, Portugal, epidemic, and they describe the macroscopic and some
microscopic lesions as follows : The buboes may be single or multiple, in
most cases they were multiple. They consist of one or more glands of
the same region. The former are increased in size in consequence of a
hemorrhagic inflammation which extends into the periglandular tissue and
sometimes into the overlying skin, producing phlyctense which may contain
plague and other bacteria. Microscopically one finds cellular debris,
masses of chromatin, few leucocytes, and many plague bacilli. In the
most profound rapidly fatal cases there are extensive hemorrhages, however,
when, death is delayed and is brought about by complications, one finds
that the contents of the bubo are true purulent material with few plague
bacilli. The authors also described the so-called cutaneous plague type,
of which, however, they saw very little in Oporto. Once they observed a
case which began as an oedeniatous, very intense inflammation of the skin
of the hand and the forearm and progressed to dark discoloration and
necrosis. In all three cutaneous cases which were observed a bubo developed
in the neighborhood of the superficial plague lesion. Skin lesions in the
shape of petechiae, ecchymoses, pustules, and hemorrhagic vesicles were also
observed in typical primary bubonic plague. The two authors observed a
case which resembled hemorrhagic smallpox. In the internal organs
congestion of the intestinal mucosa, swelling of the mesenteric glands,

40

fatty degeneration and necrosis of the liver and an enlarged spleen some-
times of good consistency, but more frequently soft and friable, were found
on post-mortem examination. The kidneys showed evidence of parenchy-
matous degeneration, sometimes with hemorrhagic foci; such were also
exceptionally seen in the bladder. The heart showed subepicardial hemor-
rhages; endocardial inflammation or valvular changes were not seen. Once
a meningitis and once a meningoencephalitis was observed. In all grave
forms of the disease the lower and posterior portions of the lungs were
found hypostatic. A pure case of primary plague pneumonia was not seen
at autopsy.

Jennings, in his Manual of Plague, gives a summary of the pathology
and morbid anatomy of the disease, in which he states that discoloration,
distinct from post-mortem lividity, caused by small or large subcutaneous
blood extravasation is almost invariably present in difTerent situations.
Papules, vesicles, or pustules may exist, also scabs or unhealthy ulcers.
The skin over buboes may show a necrotic appearance, or necrosed patches
of skin or large sloughing ulcers may also be present. Diffuse swelling
around the buboes occasioned by infiltration is often observed. The
lymphatic vessels, except those associated -with the buboes, are seldom
involved; occasionally, however, a more extensive, widespread lymphangitis
may be present. The glands may simply be enlarged, congested, or engorged,
or they may show a profound hemorrhagic condition. The hemorrhages
are often extended into the periglandular tissue and they may infiltrate
the whole neighborhood. Glands distant from the bubo are generally
swollen, congested, and engorged. Plague bacilli are abundant in the pulp
of the affected glands, but generally disappear after marked softening or
true suppuration have appeared. In septicsemic plague the glands show
very moderate changes only. In the gastrointestinal tract congestion of
the mucosa and oedema of the visceral walls are generally observed, and
petechiae in the stomach and large intestines, and to a lesser extent in the
small intestines, also occasionally more extensive hemorrhages in the
submucous tissue of the stomach occur. The solitary and the agminated
glands are swollen and congested, but never ulcerated; the retroperitoneal
and mesenteric glands are generally in the same condition and often
hemorrhagic. The spleen is much enlarged and subcapsular hemorrhages
make the surface lumpy and uneven. The liver is increased in size and
engorged, and sometimes presents a nutmeg appearance; occasionally yellow
necrotic patches are found scattered throughout the organ. Petechiae are
common on the surface. The kidneys are generally intensely imbedded in
extravasated blood; petechiae are common on the surface, also in the
pelves and calices; sometimes coagula are found in the former. Glomeruli
are engorged, all the blood vessels distended and the epithelium of the
tubules generally in a state of parenchymatous degeneration. The genital
organs are generally vmaffected, but in cases in which abortion has occurred,
the subinvoluted uterus and the ovaries are engorged and cedematous. The
lungs are generally engorged. Frequently hemorrhages are found in the
lung substance or on the surface, scattered over the pleura, or in the
mediastina. When the lungs are primarily involved or secondary pneumonia

41

supervenes, the walls of some of the alveoli are broken down by the
severity of the hemorrhages and patches of catarrhal inflammation, varying
in size, are scattered throughout the lungs. These patches are surrounded
by belts of engorged lung tissue. They may coalesce into larger patches.
Sometimes a whole lobe may thus be consolidated. The patches at first
are red and later on become gray; they are quite solid and do not float on
water. The air cells in the affected areas are filled with an accumulation
of epithelial elements, granular debris, cells resembling leucocytes,
intimately mixed into a gelatinous mass in which plague bacilli, often in
association with diplococci or streptococci, abound. The vessels in general
are dilated, the heart sometimes unaffected, more frequently soft, flabby
and friable. In all cases the right side of the heart is dilated and contains
post-mortem eoagula.

A STUDY OF TWENTY CASES OF BUBONIC PLAGUE.

The material which forms the basis of the original work of
this bulletin consists of twenty cases of plague occurring in Manila
and upon which autopsies were performed by the writer during
the period of time from February 19 to September 8, 1904. These
cases were without exception fully examined anatomically on the
post-mortem table, and also by cultural and histologic methods. In
the majority of the cases, in addition, animal experiments were per-
formed with the organisms isolated. One case which was not
completely studied has been included, because it showed the hyaline
fibrin thrombosis of the glomerular vessels which is so characteristic
in plague. ^

The histologic material was in all cases at the time of the autopsy
immediately fixed in Zenker's solution and was subsequently embed-
ded in paraffin and sectioned. In addition, in one case the material
was fixed in Flemming's solution. The stains employed in the
study of the sections were hematoxylin and eosin, eosin and
alkaline-metylene-blue, carmine and Weigert's fibrin stain, dilute
carbol-fuchsin and occasionally other stains. Dilute carbol-fuchsin,
which we found the most useful dye for smears from the organs,
is not very satisfactory in the treatment of sections, stained with
a view of studying the distribution of the plague bacillus, nor did

* The number of cases upon which necropsies were performed during the
above-mentioned period of time has been in excess of twenty; but some of
them M-ere not considered in this report because of the greatly advanced
putrefactive changes, which excluded a satisfactory anatomic and histologic
examination, or on accovmt of the late hour in the day in which, for the
sake of an immediate diagnosis, the necropsy had to be hurriedly performed,
in consequence of which a careful anatomic study became impossible.

42

we obain any good results with a modified Eomanowsky dye.
Eosin and methylene-blue is the best for exhibiting the plague
bacillus, but in using this stain one must be careful in decolorizing,
or else too many plague bacilli lose the stain and fallacious con-
clusions may be arrived at. This dye, as a rule, fades quickly in
the Tropics in an atmosphere saturated with moisture, and hence
the sections treated with it must be examined without delay, and
in a later reexamination, recoloring frequently becomes necessary.^
The twenty cases to be reported below in detail have been
classified imder the following six groups:

Cases.

Group I. Primary uncomplicated plague 11

II. Primary bubonic plague with secondary plague septico-
pyemia 4

III. Primary bubonic plague with secondary plague pneumonia.. 1

IV. Primary imcomplicated plague pneumonia 2

V. Primary plague pneumonia with secondary plague septico-
pyemia 1

VI. Primary imcomplicated plague septicaemia 1

Total 20

GROUP I. PRIMARY UNCOMPLICATED BUBONIC PLAGUE.

[Eleven cases.]

Case Xo. 1. Left Inguinal Bubo.

[Necropsy Protocol No. 1009. Post-mortem examination July 27, 11 o'clock a. m.,
about eighteen hours after death, on the body of C. S., a male Chinese, 36 years
old, from 217 Santo Cristo. Died July 26 at 4 o'clock p. m.]

Body of a well-developed, fairly well-nourished, male Chinese
about 35 to 40 years old. Post-mortem rigidity not very marked,
surface quite cyanotic; post-mortem lividity has made its appear-
ance all over the dependent parts and extends in the shape of some
irregular patches to the anterior thoracic regions. Some foamy,
slightly blood-tinged fluid escapes from the anterior nares. Ko

^ We believe the reason for the rapid change of the eosin-methylenc-blue
to be the following: It is impossible completely to dehydrate sections in
an atmosphere saturated with moisture. Hence, after a time the water
in the sections will dissolve some eosin, and the eosin solution so formed
will in its turn dissolve the methylene-blue. Whether this explanation
be correct or not, it does not alter the fact continually observed, that
sections stained with eosin and methylene-blue during the rainy season in
Manila rapidly fade and, to a great extent, become useless for the study
of finer structural details and the presence and distribution of the bacteria.

4;5

wounds or ulcerations or abrasions are found anywhere on the
surface. The left inguinal region presents a swollen area about
6 to 8 centimeters long and 5 to 6 centimeters wide, which is quite
hard, somewhat elastic, and nonfluctuating. Xo individual glands
or groups of glands can be mapped out in the swollen area. The
skin is here adherent to the underlying tissues. The hard infiltrated
area extends upwards into the inguinal canal. Dark fluid blood
escapes from the veins upon section of the body. The serous
membranes are injected and dull, and all serous cavities contain a
somewhat increased amount of slightly turbid fluid. The increase
is most marked in the abdominal cavity. The pericardium is
smooth and otherwise normal, except as to the presence of a number
of small punctiform subepicardial hemorrhages, which are dotted
all over the external surface of the heart. All diameters of the
heart are about one and one-third of the normal measurements.
The wall of the left ventricle shows considerable hypertrophy.
The left auriculo-ventricular opening is normal in diameter, the
right one easily admitting four fingers. The myocardium is quite
soft and flabb}', and pale pinkish-yellow in color. Otherwise the
heart is normal. The coronary vessels and their branches are
much congested. The lungs are normal in shape and moderately
inflated. The upper lobes are pinkish-gra}', the lower purplish-
blue in color. The latter much congested and quite oedematous.
The mucosa of the bronchi, the trachea, and the lar}Tix is swollen
and reddened and the veins injected. The epiglottis is much
injected, and the papilla circumvallatfe of the tongue swollen.
The spleen is enlarged to two to three times its average size; it is
somewhat softer than usual. The capsule is smooth and grayish-
blue in color. On section it is brownish-red. The pulp does not
protrude, the cut surface is smooth, and the trabeculge and follicles
are distinct. The kidneys are normal in size, the capsules smooth
and grayish-yellow with some purplish-gray. The capsule peels
off easil}'. On section the blood vessels are found to be injected,
the tubules light yellow, and the surface as a whole dull. The
Malpighian bodies are not distinguishable. The mucosa of the
bladder shows a very few small, submucous, punctiform hemor-
rhages. The prostate, etc., are normal. The adrenals are soft,
swollen and brownish-yellow. The serosa of the stomach is much
injected, the mucosa in an intensely hemorrhagic condition. Small
hemorrhagic spots are found all over the mucosa on the anterior

44

wall. Midway between tlie larger and the lesser curvature a
number of hemorrhagic spots have become confluent. The hemor-
rhagic spots can not be wiped oS. The lower part of the esophageal
mucosa is likewise much congested. The serosa of both the small
and the large intestine is congested and dull. The mucosa shows
hemorrhagic spots, particularly in the duodenum. The follicles
are swollen. Several Ascaris lumbricoides were found in the
esophagus. The capsule of the liver is smooth and transparent,
the external color is ochre-yellow, the cut surface is fairly smooth
and yellow to light brown. The lobules are not enlarged; the
connective tissue does not appear increased. The veins contain
much blood. The organ, as a whole, is small and peculiarly formed ;
the left lobe forms merely a small appendix to the right one. The
weight is 1,210 grams. The length of the longest transverse
diameter is 20 centimeters, the sagittal diameter (antero-posteriorly)
9 centimeters, the thickness from above downwards is 12 centi-
meters. The left lobe measures 3 centimeters from side to side, 9
centimeters from before backwards, and is 2 centimeters thick.
When an incison is made over the left inguinal bubo, it is found
that the skin is completely adherent to the subcutaneous tissue,
fascia, etc. There first escapes quite a quantity of yellow, blood-
tinged serum, and the tissue beneath the skin presents a condition
of complete hemorrhagic infiltration. The glands have become
confluent, their capsules, except that of one, being indistinguish-
able from one another. The hemorrhagic infiltration and the
oedema extend into the inguinal canal. In the left half of the pelvis
the tissues are very oedematous, the loose areolar tissue is yellowish
and almost gelatinous; and imbedded in this tissue are swollen,
softened, hemorrhagic lymph glands. The iliac glands are in the
same condition ; the retroperitoneal glands at the bifurcation of the
aorta into the common iliac arteries, and even the ones farther
up along the abdominal aorta, likewise present a similar appearance.

Smears made from the inguinal glands and from the spleen show
very numerous plague bacilli. The organisms are most abundant
in the glands.

Anatomical diagnosis. — Hypertrophy of the heart; congestion
and fatty degeneration of the kidneys; fatty infiltration and
degeneration of the liver; hemorrhagic inflammation and hyper-
trophy of the left inguinal, femoral, iliac, and retroperitoneal
glands ; hypertrophy, softening, and congestion of the lymph glands

45

in general; multiple subserous and submucous hemorrhages.
Bubonic plague.

Culture tubes inoculated from the inguinal glands developed a
typical plague growth.

Microscopic examination. — Glands : The inguinal glands, the
iliac, and the retroperitoneal, all practically show the same changes,
which, however, are more profound in the lowermost lymph nodes.
All glands contain large tracts of tissue in an advanced state of
coagulation necrosis; there is much blood extravasation, which
extends into the periglandular loose areolar tissue. The latter
also shows much infiltration with leucocytic elements. The cap-
sules of the glands are completely loosened by the same type of
infiltration. The blood vessels are dilated and engorged, and their
walls show hyaline swelling and inflamatory loosening ("Auflock-
erimg"). Weigert's method shows both solid and tubular wall
thrombi in many of the vessels of the gland substance proper, in
the capsule, and in the periglandular areolar tissue. Much fibrin
is also found in the shape of reticular deposits throughout the
sections. In some places a continuation of an intravascular throm-
bus into an extraglandular network is visible. Plague bacilli, freely
scattered throughout the sections, are found either in large masses,
in small groups, or as single individuals.

In the spleen the follicles are sharp in outline and the bound-
aries of the pulp spaces indistinguishable. The latter are densely
crowded with cellular elements among which the erythrocytes much
predominate. Besides the common small mononuclears and
eosinophilics, a fair number of large mononuclears with hyaline
protoplasm, which stains moderately with methylene blue, are foimd.
Plague bacilli are seen all throughout the sections ; however, nowhere
are they present in large groups, but thinly scattered here and
there. A few threads of fibrin are occasionally seen.

Kidneys : The renal tissue exhibits complete degeneration of the
tubular epithelium, with cloudy swelling and fatt)'' degeneration.
The degeneration is most marked in the convoluted tubules, while
in the straight tubules apparently normal epithelia are found here
and there. The uriniferous canaliculi contain a great deal of
granular material. The glomeruli show much dilated capillaries;
otherwise they present no marked changes. The renal vessels are
all much congested. The interstitial connective tissue is quite
(Edematous.

46

In the liver we find small interlobular inflammatory foci, com-
posed of small, round cells. The parenchyma cells are finely
vacuolated or coarsely granular; some of the nuclei are absent
or do not stain. Here and there a small area is found in which
all cells are degenerated (areas of focal necrosis). A few plague
bacilli are here and there seen in the capillaries, but none in the
interlobular inflammatory foci.

The consolidated areas of the lower lobes of the lungs show an
enormous dilatation and engorgement of the vessels and alveoli,
completely filled with extravasated blood and with desquamated
alveolar epithelial cells. The latter contain much dark granular
pigmentary matter. Here and there one sees in the alveoli, cocci,
a slender bacillus, and possibly a few plague bacilli. Whether
the latter are really plague bacilli is somewhat doubtful ; certainly,
if present at all, they are very scantily represented.

Case No. 2. Left Inguinal Bubo.

[Necropsy Protocol No. 989. T. C, a male Chinese, from Ilang-Ilang Street,
San Nicolas, 29 years of age. Ill two days. Died June 20, 1904. Post-
mortem examination nine hours after death.]

The body of a slender, rather jjoorly nourished Chinese. Post-
mortem rigidity is still well-marked. Post-mortem lividity is
extensive. The anterior abdominal wall presents a mottling of
greenish discoloration. The tibial region of the left leg shows two
shallow, almost healed ulcers. Both the inguinal regions are
swollen, particularly the left one. The swelling shades off into
the surrounding tissues. On the right side no individual glands
can be distinguished, because the whole region is much infiltrated
and edematous. On making an incision into this region, a consider-
able amount of slightly blood-tinged, serous liquid escapes and the
entire tissues are found to be diffusely infiltrated with blood.
The individual glands can not be distinguished, as they have become
fused into one irregular hemorrhagic mass; nor are the capsules,
the cortices, or the medullas of the individual glands distinguish-
able. No suppurative changes are observed. On the right side the
glands are swollen, softened, and highly congested. However, the
capsules are well preserved, and the hemorrhagic condition does
not extend beyond the glands proper. The other superficial glands
are not palpable. On opening the body cavities, a moderate amount
of dark, fluid blood escapes from the veins.

The abdominal cavity contains an increased amount of serous.

47

blood-tinged fluid. The hemorrhagic infiltration of the inguinal
region extends through the inguinal canal, into the pelvis, and
along the iliac vessels and left ureter upwards. The pericardium
contains a normal amount of serous fluid, but it is blood-stained,
evidently by post-mortem imbibition. The heart presents a few
small subepicardial hemorrhagic areas. The myocardium is soft
and flabby, and pink in color.

The beginning of the aorta presents an atheromatous ulcer,
surrounded by a calcareous deposit. Otherwise the heart and the
great vessels are normal. The pleural cavities contain a moderate
amoimt of blood-tinged fluid. The pleural surfaces of the lungs
are dark purple, with some greenish putrefactive areas. The lungs
are full of blood and contain but little air. The bronchi, the
trachea and, to a lesser extent, the larynx show a congested mucosa.
The spleen is enlarged to about twice its normal size. It is steel-
gray-purplish on the external surface, and brownish-red on section.
The pulp is soft. The Malpighian bodies are fairly distinct.
The kidneys are normal in size, purplish-l)lue in color. On section
they are dull and decidedly grayish yellow. They are exceedingly
soft, a condition probably due to some extent, at least, to post-
mortem changes. The mucosa of the left ureter is highly congested
and shows some hemorrhagic spots, that of the right ureter is
congested, but to a much lesser extent. The mucosa of the bladder
shows a minor degree of congestion. The liver is normal in size,
rather increased in consistency, and dark purplish in color with
some grayish-yellow mottlings. It cuts with increased resistance,
and the cut surface is yellow brown in color. The liver lobules
are increased in size. The gall bladder and its ducts are normal.
The duodenum and the stomach show a highly congested mucosa.
The gastric mucous membrane exhibits numerous small pimctate
or somewhat larger, irregular hemorrhagic spots. The follicles of
both the small and the large intestine are highly swollen and
congested. The suprarenals are swollen, soft, and dark yellowish-
brown in color. The pancreas is normal. The abdominal glands
in general are all more or less swollen, congested, and softened.

Anatomic diagnosis. — Hemorrhagic left inguinal bubo; general
lymphadenitis; multiple hemorrhages into the serous and mucous
membranes; congestion and parenchymatous degeneration of the
kidneys; congestion and fatty degeneration of the liver; bubonic
plague.

48

A microscopic examination of smears from the left inguinal
glands shows innumerable plague bacilli, most of which are oval,
or almost spherical, in form, with a narrow peripheral stained
margin, suggesting mere empty shells. Smears from the right
inguinal glands contain a moderate number of plague bacilli, which
are also quite numerous in the juice of the spleen. The heart's
blood contains several varieties of micro-organisms in moderate
numbers. Among them possibly a very few plague bacilli are
present.

Tubes inoculated from the left inguinal bubo and from the spleen
developed a typical plague growth.

Microscopic examination. — Left inguinal glands : The finer gland
structure is practically completely lost, though follicles can here
and there still be recognized to some extent. All of the vessels show
great dilatation and engorgement, and the connective tissue at the
hilum is increased; toward the periphery tracts of coagulation
necroses are seen. Here the oedema is also marked. All throughout
the glands there are found masses composed of innumerable, very
densely crowded plague bacilli. In sections stained with eosin-
methylene-blue, but which have been too much decolorized, the
bacillar masses are somewhat stained by eosin and they look simply
like ordinary granular material, for which in such improperly
stained sections they may easily be mistaken. It is particularly
the periphery of the gland which is quite extensively infiltrated
with red blood corpuscles. This extravasation extends beyond the
capsule and into the Surrounding loose areolar connective tissue,
where it is mixed with a more or less marked leucocytic infiltration.
The parenchyma cells of the glands are small mononuclears and
some plasma cells, polynuclears of the ordinary type, and a few
eosinophilics. In sections stained by Weigert's method, numerous
capillaries and other small vessels are found to be closed by hyaline
fibrin thrombi. This thrombosis is generally complete in the
smallest vessels only. In the larger ones we see an incomplete
thrombosis. The fibrin in the latter is deposited on the intima and
leaves a free space in the center of the vessel, which, however, may
show an open network of fibrin filaments. The endothelial lining of
the vessels, totally or partly thrombosed, is apparently generally
intact, although there may be seen places where the endothelia are
missing. Such losses are probably due to an artefact. The vessel
walls proper do not show any profound changes; however, a minor

49

degree of oedema and even of hyaline degeneration may here and
there be observed. No bacilli are seen in the lumina of the vessels,
either in those containing thrombi or in those free from them, in
the right inguinal glands the most pronounced pathologic change is
the increase of connective tissue at the hilum and the great dilatation
and engorgement of the vessels. The congestion is greater on the
right side than on the left. This is to be attributed to the fact that
there are only few bacilli present on the former one, while on the
latter they are so numerous as to have a tendency more or less to
crowd all of the autochthonous tissue elements. Some few of the
vessels in the right inguinal glands show a network of fibrin, how-
ever, none complete thrombosis.

The spleen sections show very numerous plague bacilli. How-
ever, they are nowhere found in dense masses as in the primary
bubo, but very abundantly as single individuals freely distributed
between the cells. The boundaries of the follicles are rather
indistinct. The pulp spaces contain numerous crowed red blood
corpuscles. In a few small vessels tubular hyaline thrombi are
seen.

The epithelial lining of the uriniferous tubules of the kidneys
shows cloudy swelling and fatty degeneration. These changes
are most marked in the convoluted tubules, but the epithelia of the
straight ones are likewise much affected. Much granular material
is found in all of the tubules. The intertubular connective tissue
is oedematous. In a number of the glomeruli the capillaries are
closed by hyaline fibrin thrombi, while other capillaries are free
and non occluded. The thrombi mostly are solid, though some are
distinctly tubular with an open lumen in the center. Occasionally
one sees a thrombus extending from a Malpighian tuft into an
afferent or efferent, or intertubular vessel. Changes of the vascular
endothelium of the thrombosed vessels are not demonstrable. All
through the renal (and also through the hepatic) tissue, fairly
numerous large bacilli, which retain. Gram's stain, are found.
These micro-organisms clearly represent a post-mortem invasion
found frequently in Manila in bodies, when the post-mortem
examination can not be made immediately but has to be postponed
for some time. Plague bacilli are not seen in the renal tissue.

In the liver the parenchyma cells are finely vacuolated ; large,
coarse vacuoles are not seen. The capillaries are dilated, par-
2.5483 4

50

ticularly those in the central part of the lobules. Here and there
a small, interlobular, inflammatory fociis, composed of mononu-
clears, is found. The interlobular fibrous connective tissue is
somewhat increased; otherwise marked changes are not seen.

In the lungs the capillaries and the veins are much engorged.
The alveolar spaces contain much granular detritus, many desqua-
mated endothelial cells and considerable numbers of large bacilli
taking Gram's stain. These organisms are also found in large
numbers in the liver and the kidneys. ISTo plague bacilli are
encountered in the sections.

Case No. 3. Left Ingxhnal Bubo.

[Necropsy Protocol No. 940. S. Y. S., male Chinese, 25 years old, from 70
Santo Crlsto, Binondo. Ill six days. Died April 14, 1904, at 5.30 o'clock
a. m. Post-mortem examination six hours after death.]

The body of a male Chinese, about 35 to 45^ years old. Well-
developed muscles and skeleton. Eigor mortis well marked. Post-
mortem lividity of a dark port-wine red color is present over the
dependent parts of the body, also around the neck, on the sides
of the trunk, and over the anterior tibial regions. The integument
in general is quite cyanotic. On the left leg over the sharp edges
of the tibia, midway between the ankle and the knee, are seen
three small oval ulcerations; they have the size of a split pea and
are covered with a dry, dark brown crust. Below these shallow
ulcers are about a dozen depressed, healed cicatrices of the same
size as the ulcerations. The lymph glands below the left ligament
of Poupart are swollen and the skin here is covered with tenacious
brown ointment. After its removal the integument is foimd
unbroken, but puffed up and oedematous. The round swelling
which protrudes over the surrounding skin has the size of a walnut,
feels doughy, and is rather firm ; but the individual glands are not
distinctly palpable. On section of the skin there escapes first a
small amount of yellowish, watery fluid, which becomes bloody as
soon as the subcutaneous adipose tissue is cut into. The glands
of this region have become fused together, and the individual
components of the group are indistinguishable. The whole tissue
shows an intense hemorrhagic infiltration and well-marked soften-
ing. A good deal of dark, bloody fluid can be scraped off from the
cut surface and it can be seen that the hemorrhagic infiltration

^The deceased was evidently much older than the figure given officially
in the death certificate.

51

extends beyond the glands into the periglandular and general
subcutaneous connective tissue. The capsules of the glands are
indistinguishable.

After opening the abdomen, the left iliac glands are found in
the same condition as those in Scarpas' triangle. They form a
bubo of the size of a small walnut. However, those higher up
are much less affected; they are moderately increased in size and
dark purple in color, but there is no marked hemorrhagic infiltra-
tion beyond the gland substance. The peritoneum, the pleura,
and the pericardium show deeply injected, dilated vessels. The
intestinal serosa appears dull and exhibits slight greenish dis-
coloration; shining through it are found hemorrhagic spots in
moderate numbers both in the small and in the large intestine.
The pericardium contains a normal amount of clear straw-colored
fluid. The epicardium shows greatly congested vessels and a
number of fiat, slightly elevated, yellowish-gray, old, fibrous cica-
tricial bands. These are found on the right side, over the auricle
and the ventricle. The auriculo-ventricular zone exhibits quite
a number of small petechise from the size of a pin head to that
of a millet seed. The riglrt ventricle is much distended and
contains a large amount of dark red, fluid blood ; the left ventricle
is firmly contracted and contains a small, dark red, firm clot.
The heart as a whole is moderately hypertrophied, the walls of
the left ventricle are thickened, and those of the right rather thin
and flabby. The myocardium in general is firm, and on section
of a dull, brownish-pink color. The arch of the aorta shows a
number of atheromatous patches. Both lungs are quite hea,Ty,
their upper lobes being of a slate-grayish-pink color and the lower
ones dark bluish-purple. On the cut surface the upper lobes are
moist and their vessels discharge a moderate amount of dark blood ;
the lower ones are brownish-red and their tissues are very rich in
dark, fluid blood and very poor in air. The small bronchi of the
lower lobes contain a bloody, foamy, fluid; slightly blood-tinged,
foamy, viscous fluid is also found in the trachea. The mucosa of
the bronchial tree, of the trachea, and of the larynx is slightly
swollen and much injected. The bronchial glands are not enlarged ;
however, they are very dark in color and much congested. The
spleen is much enlarged, its diameters being 34 by 12 by 5 centi-
meters. All the hilus vessels are much enlarged. The capsule is
smooth and transparent everywhere, except in one place at the

52

upper convex surface, where it is somwliat thickened, though not
elevated, and opaque and dull grayish-white in appearance. The
cut surface of the organ is dark brownish-red; the trabeculse can
be seen very well and are distinctly thickened; the pulp is moder-
ately soft; and a moderate amount of juice can be scraped off the
cut surface. The Malpighian corpuscles are not distinguishable.
On the whole the consistency of the spleen is rather increased than
decreased. Its weight is 675 grams. The kidneys are normal in
size, much congested, and the capsules are rather dull and not very
translucent. The outer surface is dark purplish-blue. Here and
there a grayish-white mottling is seen. The capsules peel off
easily. On the cut surface the vessels appear injected, the tubules
decidedly grayish-yellow. The glomeruli are not very distinct, and
the pyramids are dark pinkish-purple in appearance. The relation
of the cortex to the medulla is normal. The mucosa of the pelvis
is smooth and much injected, so that the small vessels are distinctly
visible. The suprarenals are normal in size, moderately injected,
yellowish-brown in color, and somewhat softened. The liver is of
normal size, the capsule very tense, shining, and transparent. The
external color is bluish-purple. The cut surface discharges a rather
moderate amount of dark, fluid blood. The liver lobules are
distinct and of a dark brownish-yellow color. The gall bladder
is distended with very dark, turbid, pitchy bile. The mucous
membrane is swollen. There are no stones. The ducts are normal.
The serosa of the stomach and intestines is injected, that of the
latter being of a dull appearance, as before described. The dark
spots seen through the intestinal serosa correspond to hemorrhagic
spots of the mucosa. The gastric mucosa shows numerous small,
punctiform petechige on a dirty grayish background. The pancreas,
the prostrate, and the bladder show no particular changes.

Anatomic diagnosis. — Hypertrophy and hemorrhagic inflamma-
tion of the left inguinal and iliac glands; passive congestion and
parenchymatous degeneration of the kidneys ; congestion and oedema
of the lungs; multiple subserous and submucous hemorrhages;
moderate hypertrophy of the heart; old epicardial cicatrices;
atheroma of the aorta; splenomegaly. Bubonic plague.

Smears made from various organs show the following : From the
primary bubo, quite a number of very poorly staining oval or round
bacilli. Only a very small peripheral rim has taken the dye; the
center is entirely unstained. These bacilli appear as empty shells.

53

Another bacterium present is a long, slender, well-stained bacillus.
The juice from the spleen contains a moderate number of plague
bacilli ; that from the liver and the kidneys a few only ; none at
all are found in the smear from the heart's blood. Cultures
inoculated from the inguinal glands and from the spleen developed
plague bacilli; a tube from the liver remained sterile.

Microscopic examination. — The glands of the inguinal region
show a marked increase of connective tissue and thickening of the
walls of the vessels at the hilum. While some portions still
exhibit a fairly normal lymphoid tissue others are thoroughly
infiltrated with extravasated blood. The loose, areolar, pericapsular
connective tissue is infiltrated with mononuclear and polynuclear
inflammatory cells. Innumerable plague bacilli are difi:used
throughout the gland and penetrate into the periglandular con-
nective tissue. Here and there a moderate amount of fibrin is
seen, particularly around some small vessels, but hyaline thrombi
obliterating the vascular lumina are not visible. The capsule of
the spleen is not thickened, but the trabeculge are broad. The
Malpighian bodies are quite small, not sharply defined, and shade
off gradually into the surrounding tissue. The fibrillar connective
tissue of these follicles is increased. The pulp spaces are fairly
well recognizable and are densely filled with red blood corpuscles,
while a moderate number of polynuclears, some typical plasma cells,
and large mononuclear cells are also present. The last, which
appear to be proliferated endothelia of the pulp spaces, have a
large vesicular round or oval nucleus, not very rich in chromatin,
with generally one or more distinct nucleoli. A moderate number
of plague bacilli is found in the spleen sections. The kidneys
show both large and small vessels to be greatly engorged. There
is extensive cloudy swelling of the epithelium of the uriniferous
tubules, and a moderate amount of granular material is scattered
through the latter. The liver exhibits engorged capillaries and
a very moderate degree of fatty degeneration of parenchyma cells.
Very small interlobular inflammatory foci are seen in a few places.
The pulmonary tissue shows an enormous engorgement of the
blood vessels. • Most of the alveoli are open and empty, but a
moderate number contain red blood corpuscles, or more or less
granular material, in which are embedded leucocytes and shreds of
fibrin, the latter forming a network like that occurring in
fibrinous pneumonia. Plague bacilli are not found in such small

54

incomplete areas of consolidation. The stomach shows engorge-
ment of the veins of the suhmucosa. The congestion is continued
into the small veins and capillaries of the mucosa. Blood is
found extravasated between the glands and upon the surface of the
latter. The cells lining the peptic glands show evidence of nutritive
disturbance. Here and there one sees karyokinetic figures, while
a number of the sustentacular central cells show two or more
nuclei. Plagiie bacilli are not seen in the mucosa.

Case Xo. 4. Right Inguinal Bubo.

[Necropsy Protocol No. 932. F. H., young male Filipino, from 20 Alma Street,
Tondo. Died March 20, 1904, at 2 o'clock p. m. Post-mortem examination
made March 21, at 10 o'clock a. m., twenty hours after death.]

Body of an unusually strong young native, of 20 to 25 years of
age. The right heel shows a large, open, ulcerated surface about the
size of the palm of the hand, dark purplish in color, covered with
a dirty greenish libro-purulent secretion. The entire anterior
surface of both legs shows a scaly vesicular eruption. Post-mortem
lividity is well marked all over the body. The skin in general is
markedly cyanotic. Post-mortem rigidity has almost disappeared.
Putrefaction is well advanced.

On opening the abdomen a great deal of ill-smelling gas escapes.
The superficial blood vessels discharge a moderate amount of dark,
fluid blood. The serous membranes are quite dull, their vessels are
markedly injected. Heart: The left ventricle is well contracted,
the right ventricle dilated. The visceral pericardium is strongly
injected and shows a few small hemorrhagic areas. The myocar-
dium is pinkish in color, and fairly firm in consistency. Valves
normal. Endocardium smooth. The large vessels are normal.
Lungs: Slightly adherent to the pleura costalis. Extensively
adherent to the upper surface of the diaphragm. The upper lobes
are pinkish in color and contain a good deal of air; the lower
lobes are highly congested and of a dark purplish color; they con-
tain but little air, are very oedematous and full of dark fluid blood.
The mucous membrane of the bronchi and of the trachea is swollen
and congested ; the air tubes contain a moderate amount of frothy,
viscid mucus. Larynx likewise congested. Spleen: Normal in
size; the capsule is smooth and slightly wrinkled and the outer
surface is dark purple in color. The cut surface is dark bro^-n, the
pulp is soft. A good deal of dark-brown juice can be scraped off
the surface. The Malpighian bodies are not distinctly visible.

55

The trabeculae are fairly well marked. Kidneys : Capsules smooth,
surface purplish in color. After removal of the capsules, which
peel off easily, the glomeruli stand out as highly injected points,
surrounded by a grayish white tissue. On section the glomeruli,
the vessels, and the pyramids appear highly congested. The
tubules are grayish wdiite. The pelves are smooth and much
congested. The surparenals are enlarged, soft, oedematous, and
congested. Brownish purple in color. Liver : The liver is some-
what swollen, capsules smooth and transparent. Outer surface
purplish gray. The cut surface is purplish brown. The vessels
discharge a good deal of fluid blood. Boundaries of liver lobules
distinct. The gall bladder is of a dark grayish purple color. Its
mucous membrane is swollen and congested. The viscus contains
a large amount of dark greenish turbid bile. No stones. Stomach
and intestines : The serosa is rather dull, showing injected vessels.
A number of small hemorrhagic spots are seen on the serosa of
the small intestines. The mucous membrane of the stomach is
grayish-white and shows a number of small hemorrhagic spots. It
is covered with dirty gray, tenacious mucus. The small intestine
likewise shows some small hemorrhagic spots in its mucosa. Lymph
glands : The inguinal glands of both sides are much swollen, rather
soft, oedematous, congested, and purplish in color. These changes
are more marked on the right side than on the left. The mesenteric
lymph glands show similar changes, though to a less degree. The
cervical glands show only a very moderate amount of enlargement
and congestion.

Anatomical diagnosis. — Large granulating ulcer on the right
heel. Congestion and oedema of the lungs. Passive congestion
of the liver and kidneys. Parenthymatous degeneration of the
kidneys, ffidema, general hypertrophy, and congestion of the
lymph nodes, particularly of those of the right inguinal region.
Multiple subserous and submucous hemorrhages. Bubonic plague.

Smears are made from the heart's blood, spleen, liver, and left
inguinal glands. The smears from the heart's blood show only
a few pest bacilli, while those from the spleen and glands show a
considerable number. Culture tubes are inoculated from the heart's
blood, spleen, and liver. The tube from the spleen developed a
pure culture of plague bacilli ; those from the liver and the heart's
blood showed a mixed culture of plague bacilli and staphylococcus
pyogenes albus.

56

Microscopic examination. — The inguinal lymph glands show
an oedematous infiltration and great dilatation and congestion of
blood vessels. The perivascular connective tissue at the hilum is
much increased. An area of extensive blood extravasation is found
near the capsule. The majority of the parenchyma cells of the
gland are small mononuclear and ordinary polynuclear cells;
plasma cells are fairly numerous, and plasma mast cells are j)\en-
tiful. Here and there are seen globular, homogeneous masses of
a diameter of 20 to 30 /a and more which have a strong affinity for
eosin. Keither the blood vessels nor the other parts of the tissues
show any fibrin. Plague bacilli are only sparingly seen in sections
of the glands. Sections of splenic tissue show mostly ill-defined
Malpighian corpuscles, obliterated pulp spaces, and an overcrowding
of the latter with red blood corpuscles. As in the lymph gland
tissue, plasma cells and plasma mast cells are numerous. Bacilli
are found in small numbers only. The renal tissue shows greatly
dilated and engorged vessels, very small areas of blood extravasa-
tion between the tubules, an occasional thickening of Bowman's
capsule, and most extensive cloudy swelling of the tubular
epithelium. While the latter is still found intact here and there,
most tubules, both convoluted and straight, are lined by greatly
swollen, irregular, hazy cells in which a nucleus is not seen, or if
seen at all, it is very poorly stained.

In the pulmonary tissue one sees enormously engorged interal-
veolar capillaries and air spaces partly filled with desquamated-
epithelia and erythrocytes. No fibrin is found in the alveoli.

Case No. 5. Right Inguinal Bubo.

[Necropsy Protocol No. 977. O. C, Chinese, 25 years, male, from 214 San Jacinto
Street. Died after an illness of two days on May 25, 1904, 9.15 p. m. Post-
mortem examination fifteen hours after death.]

Body of a young male Chinese about 25 years old ; rather slender,
but well developed. Post-mortem rigidity moderately well marked.
The skin as a whole is quite cyanotic, and the post-mortem lividity,
which has extended well to the anterior surfaces, is marked. A
small amount of dirty-brown foamy fluid exudes from the nares.
No wounds or ulcerations are to be found anywhere on the integu-
ment. The right inguinal region is somewhat swollen, but the
swelling is not high ; it is not well defined but shades off: gradually
into the surrounding tissue. The swollen area is markedly cyanotic
and cedematous, the skin here pits on pressure. On section the

57

subcutaneous connective tissue discharges a serous, slightly yellowish
fluid, and on further dissecting into the tissues an extensive
hemorrhagic infiltration is encountered. This hemorrhagic infil-
tration surrounds ill-defined, swollen, soft, and hemorrhagic glands.
The bloody extravasation extends from Scarpa's triangle through
the inguinal canal, into the pelvis along the iliac glands, thence
into the abdominal cavity up to the region of the kidney. All
lymph glands along this course are swollen, much softened, and
hemorrhagic. The same pathologic changes, though to a lesser
degree, are shown by the mesenteric, the peritoneal, the mediastinal,
and the bronchial glands. The latter are more markedly enlarged,
softened, and hemorrhagic than any other glands mentioned except
those of the chain beginning with the right inguinal glands. The
superficial lymph glands, aside from the right inguinal, are mod-
erately swollen, softened, and congested. Subserous hemorrhagic
spots are found on the epicardium, on the pleuras, on the external
surfaces of the stomach, the small intestines, the kidneys, and on
the capsule of the liver at the insertion of the suspensory ligament.
The pericardium is smooth, much injected, and contains a moderate
amount of fluid. The heart shows a number of subepicardial hemor-
rhages, varying in size from a small point to irregular spots several
millimeters in diameter. These petechise and ecchymoses are
found on both ventricular surfaces and on the sulcus. The myo-
cardium is of fair consistency. ISTo further dissection of the heart
is made, since it is to be preserved as a museum specimen. The
lungs are well expanded, their pleurae smooth, nonadherent, and
dark purplish-blue, with a moderate number of small hemorrhagic
spots and with some small elevated emphysematous areas on the
lower lobes. On section the pulmonary tissue is of dark purplish-
brown color, containing very much dark blood and foamy, aqueous
fluid. The limgs on the whole are heavy and contain but little
air. The bronchial, tracheal, and laryngeal mucosa is somewhat
swollen and greatly congested. The epiglottis is of a dark purplish-
blue color. The spleen is normal in size, the capsule slightly
wrinkled, transparent, and bluish-gray. The organ as a whole is
fairly firm. The cut surface is reddish-brown and granular. The
amount of juice which can be scraped off the surface is quite mod-
erate. The trabeculge and corpuscles are distinct.^ The kidneys

^ Many plague bacilli were found in the smears from the spleen ; yet
it was neither enlarged nor softened.

58

are much congested and very soft. Externally they are dark bluish-
gray, with some subcapsular petechia and ecchymoses. On section
the vessels are greatly engorged, the tubules grayish-white, and the
surface as a whole dull. The mucosa of the pelvis and bladder is
greatly congested. The mucosa of the ureters and the bladder is
moderately congested, but shows no hemorrhages. The suprarenals
are large, swollen, soft, and dark yellowish-brown. The liver is
large, its margins rounded, its capsule thin and transparent, and its
external color a yellowish-bluish-purple, alternating with decidedly
grayish-yellow areas. Along the insertion of the suspensory liga-
ment are seen numerous subcapsular hemorrhages, varying in size
from a mere point to a diameter of 5 to 7 millimeters. The organ
is of much increased consistency, and the cut surface is brownish-
yellow in color. The gall bladder is distended with dark yellowish-
green bile. The serosa of the stomach and intestines shows a
number of hemorrhagic spots. The gastric mucosa is studded with
small hemorrhagic areas and so is that of the duodenum, though to
a lesser extent. The lymph follicles of the intestines are swollen.

Anatomic diagnosis — Congestion of the lungs; congestion and
parenchymatous degeneration of the kidneys ; fatty degeneration of
the liver; multiple subserous and submucous hemorrhages; mul-
tiple hemorrhagic lymphadenitis. Bubonic plague.

Smears from the right inguinal glands show innumerable typical
plague bacilli ; those from the spleen show numerous pest organisms.
Culture tubes inoculated from the inguinal glands and the spleen
developed a typical growth.

Microscopic examination. — The inguinal glands show an enor-
mous dilatation and engorgement of the blood vessels, a moderate
degree of free blood extravasation, and marked oedema. A number
of the smaller blood vessels are completely obliterated by hyaline
thrombi. Other larger vessels show closely packed blood corpus-
cles and a network of fibrin between the corpuscles. The number
of leucocytes in the engorged blood vessels, including those which
show a network of fibrin, is very moderate. If at all increased over
the normal, they are not very greatly so. Any damage to the
vessel walls, which are much dilated, is not demonstrable, and
the vascular endothelium appears' intact. The cellular elements
of the gland are the same as in the other cases described above.
Plague bacilli are very numerous. However, they do not form
dense, almost solid masses, but infiltrate the intercellular spaces

59

and surround, as it were, each individual cell. Spleen : The bound-
aries of some of the Malpighian corpuscles are distinct and sharply
cut; others show an indistinct limitation, because the small mono-
nuclear cells forming the follicles are densely infiltrating the
neighboring tissues. The pulp spaces are quite indistinct, because
they are crowed with cells. Most of these are leucocytes, but in
some places red blood corpuscles predominate. All through the
pulp spaces of the splenic tissue a fibrin network can be seen. No
fibrin, however, is found in the vessels and the network has, of
course, no intravascular connection. Here and there one can see
the fibrin threads take their origin from leucocytes. Plague bacilli
are present in large numbers. Kidneys: The glomeruli do not
show any marked changes, but the capillaries of the tufts are
greatly engorged with blood. In general all renal vessels, par-
ticularly the capillaries and the smaller veins, are much engorged.
In a few places, near the capsule, smalls areas of blood extravasation
are encountered; however, none are found at a distance from the
surface. The epithelium of the convoluted tubules shows consider-
able cloudy swelling and also more profound degeneration, with
complete loss of nuclei. The tubular lumina are generally filled
with more or less granular detritus. Few, and not greatly advanced,
changes are seen in the straight tubules. No bacilli are seen in
sections from the kidneys. All parenchyma cells of the liver are
in an advanced stage of fatty degeneration and their nuclei are
either poorly or not at all stained. Aside from this degeneration
the hepatic tissue shows no marked changes. Sections from the
lungs present greatly engorged capillaries; the alveoli are partly
filled with desquamated epithelia, red blood corpuscles, and a
granular detritus. Plague bacilli are not found. In the gastric
mucosa the intergiandular capillaries are much enlarged and free
blood is found between the glands up to the very uppermost strata.
However, no blood is seen on the free surface of the mucosa.

Case No. 6. Right Inguinal Bubo.

[Necropsy Protocol No. 998. Post-mortem examination performed on July 3,
1904, twelve to eighteen hours after death, upon the body of V. D., from 17
Azcarraga Street, Tondo ; a male Filipino 17 years old.]

Post-mortem rigidity is not well marked;. it has evidently begun
to disappear. Post-mortem lividity is noticeable over dependent
parts of the body. The integument, particularly around the chest,
the neck, and the face is quite cyanotic. The right inguinal glands.

60

particularly the lowermost ones, show considerable swelling. The
latter are enlarged to the size of a walnut. The skin is unbroken.
The region is quite firm and hard, somewhat oedematous, but not
fluctuating. The boundaries of the individual glands can not be
well differentiated and the swelling shades off gradually into the
surrounding tissues. A chain of swollen indurated glands can be
felt along the spermatic canal. On opening the body, the abdominal
cavity shows a moderate amount of slightly turbid fluid. The serosa
is dull. The intestinal serosa is deeply injected, and here and there
small hemorrhagic spots are seen. The general color of the intes-
tinal serosa is varied by some greenish discoloration due to
putrefactive changes. On the right side all the iliac glands are
swollen, much congested, and more or less hemorrhagic on section.
In fact, the whole chain of glands from those in Scarpas' triangle
up to the retroperitoneal ones, and as far as the kidneys, is in
this condition. The hemorrhagic infiltration is most marked in the
inguinal glands. There it extends into the periglandular connective
tissue, -the individual glands have become confluent, and their
capsules and their finer structure have become indistinct. The
heart shows a larger number of irregular subepicardial hemorrhages,
measuring from 1 to 5 millimeters in diameter. They are situated
over the left ventricle. The myocardium is fairly firm, pinkish,
with a slightly yellowish tint. Otherwise normal. The lungs are
very slightly adherent by some few thin adhesions. The upper
lobes contain a fair amount of air and are pinkish-purple in color.
The lower lobes are heavy, congested, oedematous, and purplish-
blue in color. A few subpleural hemorrhagic spots are seen on
the lower lobes. Bronchi, trachea, larynx show an injected mucosa.
The papilse circumvallatas of the tongue are much swollen. The
spleen is 15 by 12.5 by 6 centimeters. It weighs 645 grams.
Capsules smooth, transparent, steel-grayish-blue; consistency fairly
firm. Cut surface brownish red. Malpighian bodies not very
distinct, trabeculge distinct; cut surface slightly granular, amount
of juice which can be scraped off, moderate. Kidneys normal in
size, soft; capsules smooth, peel off easily. Pinlcish purple show-
ing a few small subcapsular hemorrhages. Cut surface, vessels
injected, tubules yellowish gray, dull. Pelves smooth. The lower
third of the left ureter is dilated to three times its normal diameter.
The bladder contains several ounces of turbid urine. On the right
side posteriorly below the apex, there is seen a flat elevation about

61

the size of a split bean. There the tissue is purplish-pink and the
swelling appears somewhat like an enlarged lymph gland. On
section this part seems somewhat tubercular, and one of the nodules
projects into the vesical mucosa. Otherwise the mucosa is smooth,
moderately congested. Prostate normal. Suprarenals swollen, soft,
yellowish-brown. Liver rather small. Capsule smooth, transparent,
much grayish-yellow mottling alternating with a pinkish-purple.
On section, veins moderately filled, cut surface slightly granular,
boundaries of acini distinct ; color ocher-light brown. Gall bladder
normal. Gastric duodenal and general intestinal serosa and mucosa
injected. Lymph follicles of small and large intestines somewhat
swollen. ]\Iesenteric, retroperitoneal, and other lymph glands
swollen and congested.

Anatomical diagnosis. — Congestion of the lungs; congestion and
parench}Tnatous degeneration of the kidneys, splenomegaly, inter-
stitial hepatitis with fatty degeneration, hemorrhagic lymphadenitis
of the right inguinal glands. General hypertrophy and congestion
of lymph glands. Subserous and submucous hemorrhages. Bubonic
plague.

Smears from the right inguinal glands show numerous, those
from the spleen a moderate number of plague bacilli. No Donovan-
Leishman bodies found in the splenic juice. The liver smears
exhibit a very few plague bacilli. The culture tubes inoculated
from the right inguinal glands and from the spleen developed
typical plague colonies.

Microscopic examination. — Sections from the hemorrhagic areas
of the right inguinal glands show an abundant infiltration with
plague bacilli, particularly well pronounced in some peripheral
areas. Bacilli, while numerous, are not present anywhere to such
an extent as to form solid, clumped masses. Even where they are
most abundant there are a ie\v cells left between them. In general,
the histologic elements can be much better studied in sections of
this case than in those from glands which are simply choked by solid
colonies of the plague organism. The general characteristics of
the gland sections are a universal hemorrhagic infiltration with
marked oedema, increased diastases between the original parenchyma
cells, swelling of the fibrillar connective tissue reticulum, the
presence of numerous leucocytic elements, and geat dilatation and
engorgement of the vessels. Both in transverse and in longitudinal
sections of small veins, considerable damage to the vessel wall is

62

manifest. The cells forming these walls show coagulation necrosis,
hyaline degeneration, and more or less complete loss of their nuclei.
The perivascular concentric fibers are loosened and pushed apart
from each other by a leucocytic infiltration. The lumina of these
very much dilated vessels are crowded with apparently normal red
blood corpuscles, and with a slightly increased number of leucocytes.
Plague bacilli are not seen in the vessels. The original parenchyma
cells, the small mononuclears, show as a rule, a normal nucleus.
In some nuclei there is considerable pyknosis, while others are quite
poorly stained. Mononuclears, with large hyaline protoplasmic
bodies, are only rarely seen, plasma mast cells likewise are scanty.
The very numerous polynuclears are generally of the ordinary type,
a few are typically coarsely granular eosinophilics, while some have
an angular vacuolated protoplasm which does not show any granules
but stains very deeply with eosin. The infiltrating, extravasated
erythrocytes are mostly, to all appearances, normal; however, in
some places they have become agglutinated and confluent, almost
completely forming homogeneous masses, deeply staining with eosin.
No complete hyaline thrombi are found in the vessels, but a few
of the latter show an open network of fibrin. Such fibrin reticula
are also found here and there free between the cells. In the spleen
the pulp spaces show a considerable number of large, proliferated
endothelial cells. These appear to be derived from the lymphatic
endothelia lining the pulp spaces. They are generally phagocytic
cells, containing from two to twelve and more engulfed mono-
nuclears, polynuclears, and erythrocytes. The picture which the
pulp, with its many large endothelia, furnishes is much like that
seen in typical primary splenomegaly or splenic anaemia, but
the generally marked phagocytic character of the large pulp cells
is analogous to the condition found in the spleen in typhoid fever.
Plague bacilli are foimd very sparingly in the splenic sections.
Kidneys : The epithelial lining of the convoluted, as well as of the
straight tubules, is in an advanced state of cloudy swelling and
fatty degeneration. Some of the canaliculi contain a moderate
amount of granular matter. The glomeruli do not show any marked
changes. All of the vessels are much engorged and small sub-
capsular hemorrhagic areas are encountered. Liver: The veins
and capillaries are dilated and they contain much blood. The
protoplasm of the parenchyma cells shows fine, dust-like vacuola-
tion; their nuclei are generally well stained. Some of the liver

63

cells are swollen, hazy in outline, and without nucleus. The
interlobular septa contain acute inflammatory foci mostly composed
of small mononuclear cells with a few" neutrophilic and a still lesser
number of eosinophilic polynuclears. The pulmonary sections
are characterized by enormously engorged capillaries with some
blood extravasated into the alveoli. In some places an increase
of the interalveolar connective tissue is noticeable. Otherwise there
are no important changes. The microscopic examination of the
nodule found in the bladder shows it to have the structure of a
subacute inflammatory focus, composed of connective tissue fibers,
small mononuclears, and some polynuclear eosinophilics. Quite
a number of bacilli are seen in this area. They do not retain
Gram's stain; however, they appear smaller and more delicate than
plague bacillus, and they stain more uniformly than the latter.

Case No. 7. Right Inguinal Bubo.

[Necropsy Protocol No. 1000. July 5, 1904. Post-mortem examination, thirty-
nine hours after death, on the body of G. A., from No. 43 Valderana Street,
San Nicolas ; a Filipino boy about 10 years old.]

Post-mortem rigidity has disappeared and putrefactive changes
are well advanced. The skin in the region of the abdomen shows
green discoloration, as does also that of the neck. The right
inguinal region exhibits a swelling about the size of a walnut, and
here the boundaries of enlarged glands can be made out by palpa-
tion. On section, the tissues are found to be oedematous and
slightly hemorrhagic. The glands are much enlarged and hemor-
rhagic ; but their capsules can still be distinguished and they are well
differentiated from the- surrounding tissue. The latter is likewise
hemorrhagic, but to a less degree. On the cut surface the glands of
the right inguinal region appear mottled; dark-red areas predomi-
nate and alternate with grayish-white ones. Considerable turbid and
hemorrhagic juice can be scraped ofl". The glands from Scarpa's tri-
angle, through the abdominal ring, up into the pelvis, are swollen,
softened, and hemorrhagic. The right iliac glands as well as the
right retroperitoneal ones are in the same condition. The altera-
tions found in the internal organs, not considering putrefactive
changes, are as follows: Heart: Two small subepicardial hemor-
rhages; myocardium, soft, flabby, and pinkish-brown. The lower
lobes of the lungs are bluish-purple and quite oedematous, showing
a few small subpleural hemorrhages. The spleen is enlarged to
twice the size of the adult organ; it is bluish-purple externally,

64

dark brownish-red on the cut surface, and granular; much juice
can be scraped off. The trabeculae and Malpighian corpuscles
are fairly well marked. Kidneys: The right kidney is much
congested and dark purplish-blue; the cut surface shows injected
vessels and somewhat yellowish tubules. The mucosa of the
pelvis is injected and shows several hemorrhagic spots. The left
kidney is also much congested, but rather pale yellowish-gray on
the cut surface. The tubules are decidedly grayish-yellow and quite
dull in appearance. The pelvis is smooth and not markedly con-
gested. The ureters and the bladder are normal. The liver is
rather large with rounded margins and much yellowish mottling
alternating with bluish-purple areas. The cut surface is reddish-
brown and the vessels much injected. The mesenteric, retroperi-
toneal, bronchial, and other glands are all enlarged, congested, and
rather soft and juicy. There is nothing abnormal about the
intestines excepting a moderate swelling of the lymph follicles.
The serosa and the mucosa of the stomach are much injected;
there are no hemorrhages.

Anatomic diagnosis. — Hemorrhagic lymphadenitis of the right
inguinal glands; multiple lymphadenitis with great congestion and
softening ; congestion of the kidneys and parenchymatous nephritis ;
fatty degeneration of the liver. Bubonic plague.

Smears from the right inguinal glands show numerous plague
bacilli, those from the spleen only a moderate number. Tubes
inoculated from the glands developed a typical growth.

Microscopic examination. — The right inguinal glands and those
of the chain which leads into the right iliac fossa show changes
resembling those in the other cases of hemorrhagic plague buboes.
The bacilli are present in very large numbers; however, solid
masses of them are found only in a limited area. In general, they
densely infiltrate the hemorrhagic and oedematous tissue. The tis-
sue elements of the infected glands in this case include a very
considerable number of mononuclears with a large body of proto-
plasm. The latter is hyaline and stains rather well with methylene
blue. A number of these large mononuclear cells contain bacilli
in their protoplasm, and the cells of this type are the only ones
which exhibit this phagocytic tendency. That the bacilli are
really inside the protoplasm and not on top of it can be seen in
very thin sections from oedematous areas where isolated cells can be
studied. Some of these mononuclears have engulfed other cells.

65

The other cells in the gland sections are of the nsual type — small
mononuclears, plasma cells, mast cells, and neutrophilic and eosino-
philic polynuclears. A number of vessels contain a network of
fibrin. Such reticula are often seen independently of vessels in
several parts of the sections. A continuation of the intravascular
fibrin network to the extravascular reticula is nowhere demonstra-
ble. The kidneys show profound parench3Tnatous degeneration with
cloudy swelling; hyaline glomerular thrombi are not found. The
post-mortem changes in the renal tissues are very advanced, so
that the finer histological changes are not well preserved. The
liver cells are in a condition of cloudy swelling and fatty degenera-
tion with both fine and coarse vacuolation. The interacinous con-
nective tissue is much increased. The septa contain numerous
connective tissue fibers and infiltrating inflammatory cells. This
change is so pronounced as to be due evidently not merely to
plague infection but to some cause acting before the latter occurred.
The interlobular inflammatory foci do not show plague bacilli.
The capillaries and veins are much engorged. In the spleen the
boundaries of the follicles are generally sharp and the Malpighian
bodies are well differentiated from the surrounding tissue. The
pulp spaces, however, are not distinct, since they are densely crowded
with cellular elements. The red blood corpuscles predominate in
number. The different types of leucocytes include many of the
large mononuclear cells with large hyaline protoplasm, staining
faintly with methylene blue. In the spleen, as in the Ij^mph glands,
some of these large hyaline mononuclears contain plague bacilli
in their protoplasm. A few of the phagocytes contain other
leucocytes or erythroc}i;es. Plague bacilli are only sparingly found
in the splenic sections.

Case No. 8. Inguinal Bubo.

[Necropsy Protocol No. 965. R. F., native, female, 45 years old, from No. 33
Calls Victoria, Intramuros. Died May 7, 1904, at 11.45 p. m., said to have
been sick four days. Admitted to San Lazaro Hospital on May 7 at 11.30
p. m., and died fifteen minutes later. Post-mortem examination eleven hours
after death.]

The body of a strong, stout woman, about 45 years of age. Post-
mortem rigidity is well marked; post-mortem lividity is extensive.
There are large livid patches on the anterior surface of the thighs
and trunk. No petechise or ecchymoses are seen. The integument
shows several old healed cicatrices, which might have been produced
25483 5

66

by a sharp cutting instrument. There are no ulcerations, wounds,
or recent cicatrices. None of the superficial glands are palpable,
but on being dissected out, the inguinal glands on both sides are
found to be much enlarged and congested, but relatively firm and
not hemorrhagic. On section, the superficial vessels discharge a
moderate amount of dark fluid blood. The serous membranes are
shining, very moderately injected, and the serous sacs contain small
amounts of clear fluid. The pericardium is smooth and normal.
The left ventricle of the heart is well contracted and the right one
moderately dilated. The valve openings, the endocardium, etc., are
normal. The m3^ocardium is moderately soft, of a reddish-brown
color, and not very easily torn. The beginning of the aorta is
atheromatous; the coronary vessels are moderately engorged. The
lungs are slightly adherent in a few places and collapsed. Their
pleural surfaces are smooth and even. The lower lobes are uni-
formly congested; the upper ones are very moderately so and
pinkish-gray in color. The former, on section, are found to
be engorged with dark fluid blood and to contain little air; the
latter have a moderate amount of blood and more air. The bronchi
are filled with a foamy, slightly blood tinged, viscid mucus. Their
mucosa is somewhat congested, as is also the mucous membrane
of the trachea and the lar}Tix. The spleen is very much enlarged,
measuring 20.5 by 12 by 7 centimeters and weighing 865 grams.
It has retained the general shape of the organ and its capsule as
a whole is thickened and nowhere transparent, but rather opaque.
The surface is in general grayish-blue with some areas which are
grayish- white. A larger area of this type is found in the center
of the upper surface; it is slightly raised above the surrounding
tissues and quite opaque. The vessels entering at the hilum are
much enlarged in caliber, particularly the veins, which are rather
thin walled. The organ is quite firm in consistency. On section,
the pulp does not protrude over the cut surface, but is even, quite
firm, and of reddish-brown color. The trabecule are increased
in width and stand out prominently. The Malpighian bodies are
not distinct. A very moderate amount of juice can be scraped off
the cut surface. The kidneys are different in size, the left one
being much larger than the right. The weight of the former is
165 grams and that of the latter is 120 grams. Both have smooth
capsules and their external surfaces are bluish-pink in color. On
section, the vessels are found to be much engorged, the glomeruli

67

injected, the tubules grayish-white, the pelvis smooth and slightly
injected, and the cut surface dull. The liver is very firm in
consistency. Its capsule is slightly uneven and finely nodular.
The external color is grayish-yellow. The organ is rather small,
and the left lobe in particular is flat and atrophic. The measure-
ments are 22 by 12 (high) by 13 (antero-posteriorly), right lobe;
the left lobe is only 2-2.5 centimeters thick. The weight is 1,595
grams. There is increased resistance on cutting the organ. The
color of the cut surface is ochre yellow. The acini are retracted,
and the boimdaries are well marked by an increase in the interlob-
ular connective tissue. The vessels discharge a moderate amount
of blood. The gall bladder is distended and contains a deep golden-
yellow turbid bile. Its walls are normal and its mucosa smooth.
The ducts are open. The mucosa of the stomach and duodenum
are moderately injected, the injection being most marked in the
gastric mucosa. There are no petechiae or ecchymoses. The uterus
is small and hard; the uterine mucosa is thin and atrophic. The
ovaries are small and nodular. There is no fresh corpus luteum.
Otherwise the genital organs are normal. None of the internal
lymph glands show marked changes.

Anatomical diagnosis. — Splenomegaly (primary?) ; perisplen-
itis; cirrhosis of the liver with moderate fatty degeneration; con-
gestion and parenchymatous degeneration of the kidneys ; congestion
of both lungs; Banti's disease. Bubonic plague.

After the completion of the post-mortem examination, it was
thought that this was not a case of plague but one of some other
infection which had taken a speedy fatal termination on account
of a complication with splenomelagy and hepatic cirrhosis. How-
ever, the examination of the smears made from the inguinal glands
revealed the presence of very numerous typical plague bacilli.
Few such organisms were found in spreads from the spleen, the
liver, and the lungs, while none were found in the heart's blood.
Cultures from the spleen and the lungs developed a plague growth.
No bacilli grew in the tube inoculated from the heart's blood.

Tissues were taken from both lungs, the liver, the kidneys, the
spleen, and the heart, but none had been taken from the glands.

Microscopic examination. — Spleen: The capsule is markedly
thickened, consisting of connective tissue fibers, spindle-shaped cells,
and occasionally an unstriped muscle fiber. An accumulation of
round mononuclear cells exists at the inner surface of the capsule.

68

The subcapsular hmph sinus is not very distinct, though to some
extent it may be recognized. The trabeculse are thickened; their
connective tissue is poor in nucleated cells and consists mostly of
wav}' fibers. The larger arteries show considerable hypertrophy of the
adventitia. The Malpighian bodies can hardly be recognized. The
accumulation of l}Tnphoid cells around the terminal arteries forming
these bodies has become much rarified, the boundaries of the cells
have almost completely disappeared, and they are gradually lost in
the surrounding tissue. With a low power no pulp spaces can be
distinguished, but with high magnification the original ones can
be recognized, at least here and there, as narrow clefts. The predom-
inating cell element in these sections is the mononuclear type,
with a vesicular nucleus, a reticular chromatin, one or more nucleoli,
and a protoplasmic body, generally of medium and frequently of
considerable size. These cells are clearly proliferated lymphatic
endothelia derived from those which lined the original normal pulp
spaces. Therefore, the great increase in volume of the spleen is to
be attributed mainly to an endothelial proliferation, as several
writers have previously described in certain cases of primary
splenomegaly (among them the author of this report). A con-
siderable number of pohmuclear neutrophiles are also found in the
pulp spaces, as well as some mononuclear plasma cells. Eed blood
corpuscles are present to a certain extent, though they are not so
numerous as in an equal area of a normal spleen. Some of the
larger mononuclear endothelia are phagocytic, containing red or
white blood corpuscles, or both. (jSTone were seen which included
plague bacilli.) Here and there in the sections one sees dense and
more or less irregular masses about 20 to 30 /a or more in diameter,
which show a marked afiinity for the eosin stain. It was first
believed that these were peculiar cells, but it was finally decided
that they were composed of deformed, agglutinated red blood corpus-
cles, sometimes including a mononuclear or pohTiuclear leucocyte.
Plague bacilli generally arranged in small groups were found in
the pulp spaces or in the outer parts of the ill-defined follicles. A
search for the Donovan-Leishman bodies was negative. Liver : The
interlobular hepatic tissue is increased and some of the liver lobules
show marked atrophy. The septa between the acini exhibit both old
connective tissue fibers without nuclei and nucleated inflammatory
cells. Most of the latter are mononuclears of the small l}Tnphoid
t3-pe. Plasma cells are seen only very rarely, but ordinary poly-

69

nuclears are fairly numerous. The interlobular inflammatory foci
also contain the same type of eosinophilic masses described above
as occurring in the much enlarged spleen. The intralobular capil-
laries are quite distended and show an increased proportion of
polynuclear leucocytes. Many of the parenchyma cells are in an
advanced stage of fatty infiltration and degeneration. Few plague
bacilli are seen in the liver sections. Kidneys : The capsule is
somewhat thickened and a few subcapsular inflammatory foci are
seen. They are composed of small mononuclear and embryonal
connective tissue cells. The epithelia of the uriniferous tubules
are in a condition of advanced cloudly swelling or show the vacuola-
tion of fatty degeneration. The lumina of the tubules contain
desquamated cells, mere cell shadows, detritus, and granular
material. A few hyaline casts are also occasionally seen staining
with eosin but not with the fibrin dye. Some of the small veins
contain fibrin; none, however, is found in the glomerular capil-
laries. The pulmonary tissue shows engorged interalveolar capil-
laries and in some places a broadening of the interalveolar septa.
Otherwise there are no marked changes. A very few plague bacilli
are found in some of the sections.

Case No. 9. Right Ceevical Bubo.

[Necropsy Protocol No. 928. C. S., Filipina, age 5 years, from 170 Estero San
Nicolas. Sick five or six days ; three days in San Lazaro Hospital. Died
March 18, 1904, at 11 o'clock p. m. Post-mortem examination three hours
after death.]

The body of a little girl well nourished. Post-mortem rigidity
and lividity marked, the latter extending well over the thorax and
neck. The integument in general is quite cyanotic. The cervical
glands along the right side are swollen, so that the whole mass
has the size of a small apple. This region shows a very intense
cyanotic condition. The tissues are very oedematous, imparting a
doughy, almost fiuctuating sensation to the touch. The swelling
shades off gradually into the surrounding areas and in fact extends
over the whole of the right side of the face. The eyelids of the
right orbit are somewhat swollen and oedematous and completely
closed. On incising the body, a small amount of fluid blood escapes
from the veins. The stomach and the intestines are much distended
with gas. The gastric veins are much congested, the injection being
particularly noticeable in those along the larger curvature of the
stomach. The intestinal serosa likewise shows injection of its

70

vessels, and there are a number of dark, hemorrhagic spots, par-
ticularly on the ilium. The mediastinal, the mesenteric, and in
fact all of the glands which can now be inspected, are swollen,
highly congested, and dark purplish in color. The large th}Taus
persists; it is of a dark purple color and shows a number of very
dark, almost black, hemorrhagic spots. Such hemorrhages are
seen also on the visceral layer of the pericardium. The coronary-
veins and their branches are much injected. The myocardium is
fairly firm, well contracted on the left side and dilated on the right,
and of a pale pinkish color. The valves are normal. The lungs
are generally pinkish-purple in color and the subpleural veins are
much injected. The upper lobes contain a fair amount of air, but
the lower ones very little and are much darker than the former, a
good deal of dark, fluid blood escaping from them on section. The
bronchial glands are in the same condition as the others, being
swollen, softened, and highly congested. The spleen is much
enlarged, its size being more than that of a normal adult's. Exter-
nally it is dark purplish-blue. The capsule is shining and the
surface slightly wrinkled. It is soft in consistency, and on sec-
tion is of a brownish-red color and has a very soft pulp. The
Malpighian bodies are fairly well marked, but the trabecule are
not easy to distinguish. A good deal of dark brown juice can be
scraped from the surface. The liver is swollen and of a dark
purplish color with an occasional alternating grayish-white area.
Its margins are rounded. On section the veins are found to be
filled with dark fluid blood. The cut surface is pinkish-brown in
color, with some grayish-white areas. The gall bladder is deeply
injected and studded with hemorrhagic areas of a deep purple,
almost black, color. Its walls are much thickened, very oedematous,
and ahnost gelatinous in character. The mucous membrane is
swollen and its small vessels are so highly injected that they can
be seen with the naked eye as dark red tortuous lines. The kidneys
are pinkish-purple in color, with a number of subcapsular, dark,
hemorrhagic areas, which vary in size from that of a millet seed
to that of a pea. The capsule peels off easik, and on its removal
the glomeruli are seen as dark red points surrounded by rather
grayish-white areas. The tubules are grayish-white. The mucous
membrane of the pelves is smooth, but even here the small vessels
are so much injected that they can easily be distinguished with the
naked eye. The suprarenals are much swollen, oedematous, and

71

of a dark purplisli-broAvii color. The stomach contains a few
ounces of a dark greenish fluid, in which are seen grayish-white
flocculi. The mucous membrane is thrown into well-marked rugjB,
and is rather pale on the whole, but contains many very small,
irregular hemorrhagic spots. The mucous membrane of the
duodenum likewise shows numerous small hemorrhagic spots. The
pancreas is normal in color and slightly softer than usual. On
cutting into the cervical glands of the right side, the tissues are
found so highly oedematous that they discharge a considerable
amount of clear, slightly yellowish fluid. All the glands of this
region are much swollen, almost black in color, and very oedematous.
The deepest ones near the angle of the inferior maxilla, the sub-
mentals, are the largest of the group, being increased to the size
of walnuts. The cervical glands of the left side likewise show a
good deal of congestion and oedema; however, they are small when
compared with those of the right side. The inguinal glands of
both sides are swollen, congested, and oedematous. In fact, all of
the glands of the body which are examined during the post-mortem
are in this condition. The trachea, larynx, and esophagus are
highly congested. On inspection of the mouth it is found that the
front teeth are small, irregularly set, and partly decayed. The
right side of the soft palate is completely perforated by an ulcer
which has destroyed most of the tissues forming the pillars of the
fauces. The margins of the ulcer, which is about 2 centimeters in
diameter, are irregular and somewhat raised. Contracted cicatricial
tissue is found in the neighborhood of the ulcerations.

Anatomic diagnosis. — Perforating ulcer on the right side of the
soft palate; general hypertrophy; congestion and hemorrhagic
oedema of the general lymph glands of the body ; oedema and conges-
tion of the lungs; congestion and parenchymatous degeneration
of the kidneys; oedema of the gall bladder; multiple subserous and
submucous hemorrhages; syphilis hereditaria tarda. Bubonic
plague.

Smears from the. different organs show the following : Those from
the lungs a moderate number of typical plague bacilli; from the
liver a somewhat larger one; and from the spleen an enormous
number, these last showing the bipolar staining in a typical manner.
In the preparations the common involution forms of the bacilli
are also to be observed. Smears from the cervical lymph nodes
show a large number of bacilli.

72

Agar culture tubes inoculated during the post-mortem exam-
ination from the heart's blood, the liver, and the spleen developed
typical plague cultures.

Microscopic examination. — Sections from the submental glands
of the right side show much enlarged and congested vessels, general
oedema, areas of blood extravasation, varying from the accumulation
of a few red blood corpuscles to extensive and widely spread
hemorrhagic areas. The finer structures of the gland are almost
completely obliterated and the cortex and medulla are indistin-
guishable. The gland cells are mostly of the usual mononuclear
type. Here and there plasma cells are found. Eosinophilic poly-
■nuclears are very scanty. The vessel walls show little or no
change, appearing fairly normal even in the middle of areas of
extravasated blood. Hyaline thrombi are not found in the gland-
ular vessels. The whole of the tissue is densely infiltrated with
innumerable plague bacilli, which are characteristic in shape and
show polar staining. The capsule and the surrounding areolar
tissue are oedematous and infiltrated with blood. The whole peri-
glandular tissue is completely permeated by a cellular exudate. At
the hilum the vessels are enormously enlarged and the perivascular
tissue is increased and quite oedematous, so that the individual
connective fiber tissues are separated by wide diastases. In spite
of these profound changes, there is comparatively little advanced
coagulation necrosis and areas where the nuclei have lost their
staining properties are few and far between. In the spleen the
Malpighian corpuscles are generally distinct in outline, although
in some of them the boundaries have become indefinite. Here and
there one of the corpuscles shows a proliferating center with large
mononuclears, but without mitotic figures. The pulp spaces are
not distinct because of dense crowding with erythrocytes and
leucocytes. Among the latter there are seen small mononuclears,
ordinary polynuclears, and a considerable number of eosinophilic
pol}Tiuclears. There are also found fairly numerous large mono-
nuclears with large, round, vesicular nuclei and a protoplasm which
stains to some extent with methylene blue, though not as markedly
as the plasma cells. Some of these cells show two nuclei; they are
very probably proliferated endothelial cells. jSTone of them in
this case show phagoc3'tic properties. Numerous plague bacilli are
found in the pulp spaces, but very few, if any, in the corpuscles.
The thymus shows the normal lymphoid tissue with included con-

73

centric bodies of Hassall; no atrophic changes are yet noticeable.
A very prominent feature of sections of this gland is the presence
of very numeroiis plasma mast cells with large, eccentrically situated
vesicular nuclei and many coarse basophilic granules. The gland
tissue proper does not contain any extensive areas of extravasated
blood. However, the capsule and the periglandular loose areolar
tissue show considerable blood extravasation. Only very few bacilli
can be found in these sections. The renal tissue shows a moderate
degree of cloudy swelling. Many of its tubules are more or less
completely filled with a granular material, some of them containing
hvaline casts. A moderate number of glomerular vessels show
h5'aline (fibrin) thrombi. Nowhere is this thrombosis very exten-
sive or at all complete; it affects only a minor part of the vessels
of one glomerulus. The renal vessels in general are very much
congested, and a very few small areas of blood extravasation are
found. The few bacilli which are visible are found in connective
tissue — lymph clefts or in the capsular space of a glomerulus, but
not inside of blood vessels. The liver shows a few small inter-
lobular inflammatory foci and a moderate degree of fatty degenera-
tion of the parench3^ma cells. The interlobular capillaries are much
distended with blood. No areas of free blood extravasation are
seen. The mucosa of the gall bladder is practically normal,
although the walls of the organ are intensely cedematous. The
cedema and extravasated blood have infiltrated the connective tissue
so extensively that the fibers form a loose open network, the meshes
of which are filled with numerous pale, red blood corpuscles.
From the erytlirocytes the infiltrating fluid has extracted almost
all of the hemoglobin, so that they do not stain well with eosin.
The veins in the mucosa of the stomach are much dilated and are
frequently surrounded by small periphlebitic areas of cell infiltra-
tion. The congestion of the veins of the submucosa is continued
into the interglandular capillaries, from which blood extravasation
has infiltrated the tissue. Some of the extravasated blood is found
between the fixed cells of the mucosa, some of it being deposited
free on the surface. The picture seen in these sections is very much
like that found, in a menstruating endometrium. Sections from
the lungs, the heart, and the pancreas do not show any pronounced
changes. The hemorrhagic areas in sections from the different
organs were carefully examined for plague bacilli, but none were
found. Hence the changes must be looked upon as due to toxic

74

effects and not directly to the presence of the bacilli. In fact,
even in the large hemorrhagic areas of the lymph glands bacilli
were practically absent, though they abounded in the neighboring
ones formed by the fixed tissue elements. Stress is also to be laid
upon the fact that these organisms, as a rule, were not found in the
blood vessels of the sections examined. The perforating ulcer of
the soft palate, surrounded by cicatricial tissue, in connection with
the defective incisors, suggested the diagnosis of syphilis heredita-
ria tarda. It appears that the chronic syphilitic perforating ulcer
became the portal of entrance for the plague virus,

INSECTS AS PLAGUE CARRIERS.

Among the plague cases investigated there is one in which it
appears probable that the infecting bacilli were carried into the
body of the patient — a child — by Pediculi capitis. It is advisedly
stated that this mode of infection appears very probable, because
it is naturally impossible beyond doubt to be certain as to such an
occurrence. Only experimental trials on human beings could firmly
establish the possibility of this mode of transmission; but such
tests with plague bacilli are of course inadmissible.

The question whether insects, and particularly parasitic ones,
play a more or less important role in the spread of plague is still
far from being definitely settled, as the views of investigators and
writers upon this subject are diverse.

Among the modern workers on plague who first gave their attention
to insects as plague carriers is Hankin, who reports on a long series
of researches on the relation of ants having fed upon rats dead of plague
to the possible spread of the disease. He found that ants neither die
from plague nor retain the infection for any length of time. By pre-
paring extracts of ants shortly after they had fed upon rats dead of
plague, Hankin obtained a fluid which, when injected into rats and mice,
would kill and produce typical plague lesions in these animals.

Ogata, in studying a plague epidemic in Formosa, took seven fleas from
a rat dead of plague, crushed them between sterile slides, and injected
the material so obtained into two mice, one of which died, while the
other remained well.

La Bonadiere and Xanthopulides, as they maintain, by cultural methods
demonstrated the presence of plague bacilli in a mosquito ( ?) (moustique)
which had bitten a patient sick with plague.

Simond is inclined to attribute much importance to rat fleas as plague
carriers. In fleas taken from rats infected with the disease he foimd
bacilli siinilar morphologically to those of plague. He inoculated three

iO

mice with material obtained from such fleas, but only one of them died,
the other two survived.

Loir goes so far as to see the principal intermediary carrier of plague
between rat and man in the flea. But, as Galli-Valerio has pointed out.
Loir has really no valid experiments to support his claim, which he
sees fit to bring forward as a demonstrated fact.

Kolle has systematically attempted to infect healthy rats from those
sick with or dead of plague through the agency of fleas. However, he
has never succeeded in transmitting plague in this manner, though he
was able to demonstrate that fleas had really traveled from the sick rats
to the healthy ones. From his observations on rats he thinks that the
disease spreads among these animals because the living eat the cadavers
of the dead of their own kind and not because of fleas which pass from
the plague-sick to the healthy individuals. The primary bubo in rats
dead of plague is generally found in the submaxillary region, which
points to an infection through a slight lesion of the buccal mucosa. Kolle,
in speaking on this subject, very properly remarks: "It is clear that
plague bacilli will enter the body of parasitic insects which suck the
blood of animals sick with the plague. It has, however, not yet been
shown beyond doubt that the bite of such parasites w^ill infect other
healthy animals."

Nuttall made experiments to clear up the question as to what part
insects play in the spread of plague. He demonstrated that when flies
had been fed on material containing plague bacilli they still harbored
the virulent organisms twenty-four and even forty-eight hours after the
last feeding. According to this author, the danger of a spread of the
disease through bedbugs is negligible. The evidence in favor of the "flea
hypothesis" as far as the spread of plague is concerned, Nuttall considers
worthless and unable to withstand scientific criticism. He states that
all of his attempts to infect rats or mice through the bite of freshly infected
fleas have proved futile.

Galli-Valerio severely and justly criticises the evidence so far brought
forward to show that rat fleas play the most important part in the
dissemination of plague among the human inhabitants of a district
infected with this disease. He particularly shows that most of those
who, on very insuflicient evidence, assumed tliat fleas from rats spread
the plague among human beings, have not even ascertained whether the
species of fleas infesting the rats will bite man. Galli-Valerio found
Typhlopsylla musculi and Pulex fasciatus on European rats and mice under
normal conditions. He allowed himself to be invaded by fasting individuals
of these two flea species, but neither of them bit him. By this investigator
Pulex serraticeps, the flea infesting dogs and cats and which occasionally
bites man, was not found on rats.

Tidswell, who made his observations during the latest plague epidemic
at Sydney, reports that he collected one hundred fleas from rats, of
which ten were identified as Pulex fasciatus, eight as Typhlopsylla musculi,
one as Pulex serraticeps, and eighty-one as Pulex pallidus. Tiie last one,
it appears, has not previously been mentioned as occurring on ordinary

76

rats; its stated hosts are, according to Thompson, Mus albipes of Socotra
and Herpestes ichneumon of Egj-pt. This species, the author states, bit
human beings in laboratory trials, as did also Pulex fasciatus on one
occasion. Typhlopsylla miisculi did not bite.^

Thompson, who, during the Sydney epidemic, observed blebs which he
considered to be produced by fleas and to be the place of entrance of
the plague virus, concludes that the transmission of plague from rats
and mice through the intermediation of fleas must be frequent.

Zirolia believes that plague can easily be spread by fleas. He observed
Pulex irritans and P. serraUceps, after they had been fasting for some
time, to suck blood from a plague-infected mouse, and he found living,
virulent plague bacilli in the bodies of these fleas seven to eight days
thereafter. Zirolia also says that the feces of fleas from plague-infected
animals contain virulent bacilli, and that in the bodies of the dead
fleas these parasites survive for a long time.

Maxwell, from his observations made at Changpoo, China, states that
he is coming more and more to doubt the rat-flea theory. "I can not
see," he says, "how we can escape plague. I must have been bitten,
in spite of flea powder, many times off plague patients and so must
my students. The Chinese, especially the women, catch the fleas and
kill them with their teeth. If they catch fleas with plague bacilli in
them, how do they escape?"

The Indian Plague Commission, which studied plague in all of its
phases in India, has also looked into the question of insects as carriers
of the disease, and in its report states that Simond's endeavors to
establish the proposHion that suctorial insects play an important part
in the transfer of plague from sick to healthy animals is so weak as
hardly to deserve consideration. The experience of plague hospitals in
India, and especially that of the Arthur Road Hospital at Bombay, seems
to indicate very clearly that suctorial insects do not come into consideration
in connection with the spread of plague. The staff and attendants in
the Arthur Road Hospital (where thousands of plague cases are treated)
were continually bitten by insects, especially mosquitoes, and yet no cases
of transfer of the infection from the sick to the healthy came under
observation.

The commission also states on reviewing all the facts which have come
to its knowledge, that it has little reason to suppose that ordinary, casual
contact with plague-infected rats, dead or alive, is especially liable to
convey the disease. On the other hand, examples are known of cases
where the bite of plague-infected rats and other animals has conveyed
the disease.

^ Galli-Valerio, trying to invalidate Tidswell's observations, says that
this author, like others, failed to transmit plague from rat to rat through
the agency of fleas and proposes the question: "If the transmission is so
difficult from rat to rat, why, on the other hand, should it be so frequent
from rats and mice to man, who is not as a general rule attacked by
mouse and rat fleas?"

77

However, the report of the commission does contain some information
which suggests that pediculi may be factors in the spread of plague.
According to the Bombay statistics of the plague epidemic of 1896, the
rate of mortality per 1,000 individuals among the Jains ^ of that city
as compared with that among other castes is surprisingly large,' and it
is believed to be due to the fact that animal life is sacred among the
Jains. "They will not." the report states, "sweep their staircases, or
sweep their sleeping rooms, or their cooking rooms very often, lest they
should destroy some animal life, so scrupulous are they. * * * Xot
that their places are very dirty. They are a wealthy people, and their
places look comparatively clean. * * * The Jains, owing to their
aversion to taking life, are said to be infected with parasites."

A NEW SPECIES OF RAT FLEA.

As yet much evidence certainly has not been presented in favor
of the theory that the most important intermediaries in the spread-
ing of plague from rats to man are fleas from plague-infected
rats. Even if rat fleas should have played an important role in
the spread of plague in Sydney, as maintained by Tidswell and
Thompson, their conclusions can not be generalized. How neces-
sary it is to study this question in every place where plague occurs
endemically or epidemically is shown by our observations of the
rat fleas in Manila. Looking into this subject, we found, somewhat
to our surprise, that the fleas infesting rats are not identical with
those which have been described for other countries. Indeed, the
species found here on rats appears to be new. Previous to the
time when the writer began to collect rat fleas. Dr. W. B. Wherry,
bacteriologist of this Laborator}^ had already collected eight, which
he kindly placed at my disposal. Thirty-four were subsequently
caught. It is not easy to procure a large number of rat fleas,
because, when the rodents have been caught, by the time they are
killed and examined, the fleas have left them. For this reason
Dr. Wherry succeeded in obtaining only eight fleas from flfty-
three rats; while the thirty- four others were subsequently obtained
from about one hundred animals. A few of the parasites were
procured alive, were kept in a glass vessel for some time, and were
then given an opportunity to bite both Caucasians and native
Filipinos. In not a single instance did any of these fleas bite
human beings. We have also collected a number of fleas from

^Average mortality per 1,000 males in the plague epidemic of 1896 at
Bombay, 2.63; per 1,000 females, 1.88; per 1,000 male Jains 8.69; per
1,000 female Jains, 6.77.

O^ THE

VERSITY

OF

78

persons working in the old laboratory, where numerous animals
were kept and where large numbers of rats were sent for examina-
tion for plague infection; these fleas proved to be Pulex irritans
and Pulex serraticeps. The flea occurring on rats in Manila was
never found on human beings.

I am indebted to Mr. W. Schultze, assistant entomologist of this
Laboratory, for the greater part of the following description of the
flea found on rats in Manila:

Pulex pMlippinensis, sp. nov., Manila, July 19, 1904.

Head, with very small bristles; front of head high and rounded.
Eyes round. Above the latter and directed backward are the
antennae, which are club shaped and consist of three segments.
First and third segments equal in size; the third segment cup
shaped; the second segment very small. Superior maxilla elon-
gated, triangular. Palpi maxillarum consist of four segments, of
which the last is the longest. The posterior margins of the
thoracic segments possess each a row of flne bristles, as do also
the abdominal ones. On the latter the bristles extend from the
back downward to the middle of the abdomen, and from below
upward. On the back, on the posterior margin of the eighth abdom-
inal segment are two large bristles. In the male, below the
external genitals, two large bristles on each side— i. e., four in all.
Abdomen of the male bent upward. In the interior of its abdomen
are the spinally curved internal sexual organs, more or less distinct
in different individuals. The abdomen of the female is oval and
egg shaped. Bristle on the ninth segment around the external
genitals. In the abdomen of the female between the seventh and
the eighth segment is an intestine or sausage-like curved organ — the
ovary. Behind it in one individual are several barrel-shaped ova.

The longest bristles are found at the lower ends of the femora.
They measure 0.2 millimeter in the female and 0.15 millimeter in
the male:

Color: Light reddish-brown.

Size of the female: Length, 1.8 to 2.67 millimeters; breadth,
0.80 to 1.25 millimeters.

Size of the male: Length, 1.16 to 1.78 millimeters; breadth,
0.70 to 0.75 millimeter.

Size of the ova: Length, 70 /x; breadth, 55 fx.

Types in the collection of the entomological division of the

79

Biological Laboratory, Bureau of Government Laboratories, Manila,
P. I.

Pulex philippinensis appears to be a stationar}' parasite of the
rat; it is found in Manila. It is much like P. anomalus recently
described by Baker and found by him in California. However,
the head, eyes, antennae, palpi, and bristles offer marked points of
differentiation.

It is of interest to mention that Baker in his monograph on
American Siphonaptera describes a new species of rat flea from
Brazil, South America. It is a very large one, the male being
3.5 millimters and the female 5.5 millimeters in length. Evidently
there are several different species of rat fleas in different parts of
the world.

EXPERIMENTS WITH FLIES.

Experiments which have been made to demonstrate that plague
may be spread by flies are all inconclusive, because the arrange-
ments were such that the transmission of the disease was inevitable.
Flies were fed with bouillion containing plague bacilli and after
varying intervals of time had elapsed were groimd up. The
emulsion so obtained was subsequently injected into guinea pigs
or rats, which of course died of the disease. Such experiments
can not determine with certainty whether plague can or can not be
carried by flies.

Experiments were therefore conduct which were designed more
closely to imitate what might take place in nature. The organs
of plague cases, both from man and from guinea pigs, were kept
in an anatomical jar, over which was placed a flytrap containing
a number of flies. The door of the trap was then opened and
the files allowed to come in contact with the plague organs in the
lower vessel. After the}' had remained in the lower vessel for
varying periods of time (from one to several hours) they were
again induced to enter the trap by surrounding the lower vessel
with some dark material, which caused them to seek the upper
light space. The trap was then closed and placed over an especially
constructed fly-proof cage, in which were two guinea pigs. The
door of the trap was opened so that the flies could enter the cage.
The guinea pigs had been shaved over an extensive area of the back
and some sirup had been dropped on a few spots, to attract the
flies and to cause them to come in contact with the bodies of the

80

animals. This experiment was performed twice; but in neither
case did the guinea pigs contract plague. It had been proved by-
preliminary trials that the flies which had been allowed to come in
contact with and to eat from the organs of plague cases had bacilli
either in or on their bodies. Flies which had been allowed to come
in contact with plague organs were then caught in the trap,
chloroformed, picked up with sterile forceps and dropped into
slightly alkaline bouillon; in every case a growth of plague bacilli
was observed in the media in which they were placed.

Another observation, which was not made experimentally but
under perfectly natural conditions, may here be recorded. The
San Lazaro morgue at Manila, a building so constructed as to be
insect proof, owing to the inclemency of the weather soon became
in such a condition that flies could readily go in and out in large
numbers. During post-mortem examinations on plague cases flies
generally passed freely from the dissected cadavers to those making
the examinations as well as to others present, and undoubtedly
also to the outside of the building; yet no cases of plague have
occurred in the part of the city where the morgue is located.
However, this part of the town is only sparingly inhabited. Hence,
no case can be attributed to flies as carriers of the infection.

When one takes what has been said above into consideration,
one is certainly inclined to conclude that insects, as a rule, do not
probably play a very important role in the spread of plague.
However, the observation that this disease is exceedingly prevalent
among that caste in Bombay which is probably more infected with
pediculi than any other suggests that certain parasites may be
operative in its transmission. As stated in the remarks intro-
ductory to this part of the paper, one of the cases here observed
strongly suggests that pediculi may be carriers of the infection.

A CASE OF BUBONIC PLAGUE IN A CHILD, IN WHICH THE
INFECTION WAS POSSIBLY CARRIED BY PEDICULI.

Case No. 10. Cervical Btjbo,

[Necropsy Protocol No. 910. C. S., a Filipina girl, 9 years of age, from Anda
Street, Intramuros, Manila. Post-mortem examination five hours after death,
on Saturday, March 5, 1904, at 4 p. m.]

The body of a female child, 9 to 10 years of age, well developed.
Post-mortem rigidity strong. Post-mortem lividity well marked
and extending over the sides of the body, being particularly notice-

81

able around the neck. The cervical glands on both sides are swollen,
imparting a doughy sensation to the touch. The tissues in the
neighborhood of the swollen glands are quite cedematous. The
integument of the bod}^ shows no lesions. There is no discharge
from the ears ; nor does the external meatus on either side show any
ulceration. The mucous membrane of the Iniccal and nasal cavities
is congested, but otherwise normal. The scalp is infested with
numerous pediculi, which seem to be ill at ease and run about
as if disturbed. On section the superficial veins of the body dis-
charge a moderate amount of very dark, fluid blood. The heart is
i\ormal, except that the superficial, subepicardial veins are much
injected. The myocardium is somewhat soft, dull, and rather pale
pinkish-yellow in color. The lungs are pinkish-purple. The lower
lobes on the cut surface are dark reddish-brown, containing much
dark, fluid blood and little air. Some of the areas seen on section
are in a condition of almost red hepatization, containing a very
large amount of dark, fluid blood. The mucous membranes of the
bronchi are slightly swollen, hyperemic, and moist. The tracheal
mucosa is in the same condition. The larynx is much injected,
particularly the epiglottis. The bronchial glands are dark purplish,
slightly swollen, and somewhat softened. The spleen is of medium
size. The capsule is smooth as a whole, though slightly wrinkled
and grayish-blue in color. The cut surface is reddish-brown. The
trabeculge are well marked; the Malpighian bodies are fairly well
visible. The mesenteric glands are reddish-purple, swollen, and
rather soft. Both kidneys show fairly numerous subcapsular hemor-
rhagic areas, varying in diameter from about one-haf centimeter to
a mere point. The capsules peel off easily, and after their removal
the surfaces show alternating areas, either deeply injected or
grayish-yellow. On section the vessels appear highly congested
and the glomeruli stand out as deep reddish-yellow points. The
tubules are grayish-yellow; the pyramids are deeply injected. The
mucous membrane of the pelves is smooth and slightly swollen,
but not hemorrhagic. The substance of the kidneys is soft and
almost gelatinous. The suprarenals are large, swollen, congested,
and very soft. The surface of the liver is bluish-pink, mottled
with pale grayish-yellow areas. The capsule is smooth. The cut
surface is grayish-yellowish-pink. The veins contain a good deal
of dark, fluid blood. The gall bladder contains a turbid, yellowish

25483 6

82

bile. The mucous membrane is smooth. The serosa of the stomach
and intestines is injected. The superficial veins are marked as
reddish lines. The mucosa as a whole is moderately injected, with
punctiform hemorrhages in the ventricular portion. The intestinal
lymph follicles are somewhat swollen. The peritoneal covering of
the uterus and tubes is much injected. All of the fine super-
ficial vessels are visible in consequence of the marked congestion.
The cervical glands on both sides, including those along the sterno-
cleido-mastoid muscles and the deeper submental ones, are enlarged,
highly congested, and softened. On section a good deal of dark,
bloody fluid can be scraped from the surface.

Anatomic diagnosis. — Hemorrhagic, acute, parenchymatous
nephritis; congestion and oedema of the lungs; moderate fatty
degeneration of the liver; hemorrhagic inflammation, hypertrophy,
and softening of the cervical glands on both sides ; more or less
general hypertrophy of most of the lymph glands. Bubonic plague.

Smears from the cervical glands show numerous plague bacilli,
but those from the spleen only a moderate number.

Before the body had been opened, three pediculi were picked up
from the scalp with sterile forceps and dropped first into an
empty sterile test tube and later into three fiasks containing 50
cubic centimeters of sterile, slightly alkaline bouillon. All of the
three flasks developed cultures of plague bacilli. The cultures
were then transferred to various media and the bacteria were
fully identified as typical plague organisms. One culture from the
spleen and two from the cervical glands likewise developed plague
bacilli.

Since this child, dead of bubonic plague, had come from a dis-
trict which had been considered plague free for some time, inquiries
were made as to the possibility of the girl's having been infested
with pediculi from some one living in an infected district. Dr.
E. E. S. Newberne, district medical inspector, reported on the
matter as follows :

So far as the records show, only two cases of bubonic plague, prior
to the one under discussion, have occurred on Calle Anda, the first in
1900 at No. 11, and the second in 1901 at No. 137. These numbers being
at a considerable distance from No 89, and in opposite directions, it may
be assumed that the district is not infected. The orphan, C. S., was taken
to 89 Anda from the Hospicio de San Juan December 24, 1903, and remained
in good health until the last days of February, when she became ill,

83

complaining of earache and fever, which did not yield to local treatment.
The patient was sent to San Juan de Dios Hospital about March 4,
where she died twenty-four hours later, after an illness of nine days.
So far as can be ascertained, this child did not handle rats or do anything
else to which infection could be ascribed. She slept on a petate on the
floor of one of the upstairs rooms, as is the native custom. With the
exception of the time from the 7th to the 16th of February, when she
attended the public school on the corner of Victoria and Magallanes, she
did not associate with children outside her home. The family assert
that she was free from vermin when she was sent to the hospital, though
it was admitted that Filipino children are generally infected with Pediculi
capitis. Five bedbugs found in a crack of the floor upon which she slept
and thirteen rats, only one of which was foimd alive, were sent to the
Laboratory on March 11 for examination.

Mr. Chas. B. Hare, assistant bacteriologist in this Laboratory,
who examined the rats, did not find any evidence of plague in
them. Smears were made from the five crushed bedbugs, which
likewise did not show any plague bacilli. It was intended to
test the bedbugs by cultural methods, but this was overlooked by
mistake.

Microscopic examination. — Sections from the cervical glands
show, even on a superficial examination, a number of most profound
changes, namely: (1) Almost complete loss of the normal structure
and differentiation of the gland into cortical follicles and medullary
cords; (2) advanced coagulation necrosis; (3) extensive extravasa-
tion of blood; (4) deposit of granular and fibrillar fibrin; (5)
the presence of enormous solid, irregularly distributed masses of
bacteria. The deeper portions of the cortex still present some
oval compartments outlined by fibrous connective tissue, evidently
once the trabeculse; however, the latter do not contain normal
lymph follicles, but masses of necrotic tissue and free extravasated
blood. Where the dense masses of bacilli are located, there are few
tissue elements left. The cells which are still recognizable as such
are the mononuclears; their nuclei generally show a marked pyk-
notic condition. At the margins of the bacillar masses and clumps
are mononuclear cells more normal in character, among which are
found quite a few polynuclear eosinophiles. Almost as numerous
as the latter are the plasma mast cells. The bacilli are found also
in the tissues, next to the large colonies ; here the micro-organisms
do not form solid, dense masses, but are freely distributed among
the cells. Intimately mixed with the leucocytic cells and the
bacilli are numerous red blood corpuscles. The peripheral tissue,

84

next to the capsule, shows a dense infiltration with completely degen-
erated erYthroc3'tes and contains hematoidin and hemosiderin.
This zone appears as a part of the former lymph sinus; however,
this can no longer be distinctly recognized as such. Here, likewise,
numerous bacilli are found. Fibrin is quite irregularly and exten-
sively distributed throughout the gland. In its interior it is
observed to be in the form of a granular deposit and also in the shape
of finer or coarser threads. Around the dense masses of bacilli
it occurs in the form of fibrillar network, sending fine threads into
the masses of micro-organisms. The tissue next to the capsule —
i. e., the former Ij-mph sinus — likewise contains a network of fibrin.
The small vessels are more or less completely occluded by hyaline
(fibrin) thrombi, which are seen both in the interior of the gland
and in the capsule. Here and there the fibrin extends from the
interior of the vessel, through its wall, into the perivascular tissue.
In the blood vessels bacilli, if found, are present in scanty numbers.
Kidneys: The renal tissue presents a most striking picture. Sec-
tions from both kidneys, treated by Weigert's fibrin method, appear
as if the vessels had been injected with a violet-stained gelatin.
There is not a normal glomerulus to be seen. All the sections
show a more or less complete obliteration by hyaline thrombi. In
most of the Malpighian bodies the hyaline thrombosis of the capil-
laries is so perfect that both the main branches of the afferent
vessel and the smaller capillaries given off from the larger loops
are sharply outlined. Most of the thrombi appear perfectly solid;
however, some are hollow in the center, as can be seen both in
transverse and in longitudinal sections. The endothelial lining
of the thrombosed vessels is well preserved. Where the thrombi
are comparatively thin, one can see, both in the transverse and in
the longitudinal sections, endothelia which are perfectly normal
to all intents and purposes. Xowhere do the thrombosed vessels to
any extent show a loss of endothelia. Therefore, the thrombosis
can not be attributed to a denudation of the vessels of their endo-
thelial lining. The capsules of Bowman are likewise normal,
though a few of them show a very moderate amount of thickening ;
their lining epithelium exhibits no marked changes. In some
places the hyaline thrombi are continued into the vasa afferentia,
and even into the vessels of which these are branches. Quite com-
monly there are seen between the uriniferous tubules parts of such
small vessels filled with hvaline thrombi. However, none are found

85

in the larger arteries or veins, in some of which finel)^ granular
fibrin and desquamated endothelial cells are present. The vessel
walls themselves show no damage aside from a minor degree of
denudation of the intima. Tliere is in particular no extension
of the fibrin through the vessel walls, nor is there any evidence
of mesophlebitic or periphlebitic — or arteritic processes. The
epithelia lining the convoluted uriniferous tubules are somewhat
swollen, with indistinct outlines and a vacuolated protoplasm; but
their nuclei are yet quite normal. A granular material partly fills
some of the convoluted tubules. The epithelial lining of the
straight tubules does not show any marked changes. The capsule
of the kidney is normal. Nowhere do any of the renal blood vessels
show a large number of plague bacilli ; a few are possibly seen inside
some vascular lumina ; but even this is not certain. A moderate
number of l)acilli are seen in the lymph clefts between the tubules
and around the Malpighian bodies. A few slender, long bacilli,
which retain Gram's stain, are occasionally found in the tubules;
but they are probably of no significance and represent an agonal
or post-mortem invasion. Sections of the liver show a very few
small periphlebitic inflammatory foci composed of small, round
mononuclears. The liver cells all show a coarse vacuolation, some
of the vacuoles being larger than the nuclei. The capillaries are
moderately filled. There is no free extravasated blood. A very
few plague bacilli are found between the liver cells.

Case No. 11. Right Inguiival Bubo.

]S3"o complete necropsy protocol was kept. Body of a male Chinese,
20 years old. who died after an illness of seven days. Sections of
the kidneys show hyaline fibrin thrombosis of the glomeralar capil-
hiries. with an extension into the afferent and efferent vessels as
well as into the intertubular capillaries and small veins. There is
general vascular dilatation and engorgement and cloudy swelling
of the epithelia of the uriniferous tubules. In the spleen, which
contains numerous plague bacilli, there is found a liomogeneous,
eosin-staining material, which is apparently derived from red
blood corpuscles which have become confluent. At the margins of
the homogeneous material erythrocytes singly and in groups may
be distinguished. Coarse fibrin threads, forming a network, are
here and there seen in the homogeneous material. Hyaline fibrin
thrombi are likewise encountered in tlie small splenic vessels.

86

GROUP II. PRIMARY BUBONIC PLACUE WITH SECONDARY
PLAGUE SEPTICO-PYEMIA.

Case No. 12. Right Ixguixal Bubo with Secondary Plague

Septico-Pyemia.

[Necropsy Protocol No. 1011. M. N., Filipino male, 40 years old, from 77
Sacristia Street, San Nicolas. Ill six days; died early July 29, 1904.
Post-mortem examination about six hours after death.]

The body of a middle-aged man, about 40 to 45 years old, in a
fair state of nutrition, and strongly built. Post-mortem rigidity
strongly marked, as is also post-mortem lividity on dependent
parts. There are no wounds or abrasions. The right inguinal
glands are swollen. Here the tissues are hard, infiltrated, and
oedematous. Individual glands are not distinguishable. None of
the other lymph glands, with the exception of the left inguinal ones,
are palpable. Much dark, fluid blood escapes from the vessels
when the body is opened. All the serous membranes are highly
injected and reddened and numerous hemorrhages, to be more
fully described, are seen. The pericardium, aside from congestion,
is normal. The heart shows a number of subepicardial hemorrhages,
varying from one to several millimeters in diameter. The left
ventricle is well contracted and the right one dilated. The myo-
cardium is rather soft, pinkish-yellow, and dull in appearance.
Otherwise the heart is normal. The beginning of the aorta pre-
sents several raised, hard, atheromatous patches. The lungs are
heavy and externally are bluish-purple, with black patches and
subpleural hemorrhages. The right apex is adherent and con-
solidated, and at its very point there is an emphysematous . cystic
bladder of the size of a hazelnut with a smaller one of the size of
a pea. These vesicles contain air and collapse on being cut in to.
The apex as a whole is consolidated, and this area contains fibrous
and calcarepus nodules. The lungs, on section, are generally dark
brown and contain much blood and oedematous fluid. The bron-
chial, tracheal, and larjTigeal mucosa is moist, swollen, and deeply
injected. The epiglottis is uneven and dark red in color. The
papilla circumvallata of the tongue are much swollen. The spleen
is enlarged to from two to three times its normal size and is firm
in consistency. The capsule is smooth and steel-grayish-blue. The
cut surface is smooth and rather light brownish-red. The pulp is
not softened and does not protrude. The trabeculse are easily
visible: the Malpighian bodies are less so. The kidneys are normal

87

in size. The capsule is smooth and in general grayish-blue in
color, with numerous and large subcapsular hemorrhagic areas.
On section the vessels are engorged, the tubules grayish-yellow, and
the surface dull in appearance. The pelves are smooth but highly
injected, with several hemorrhagic spots. The ureters likewise
show hemorrhages. The bladder is contracted and its wall firm;
its serosa is highly injected. The mucosa is swollen, congested, and
studded with small hemorrhagic spots. This organ contains 25
to 35 cubic centimeters of a coagulated, gelatinous, bloody material.
Liver: The capsule is smooth and pinkish-purple, with a good
deal of yellow mottling. There are confluent, subcapsular hemor-
rhagic spots on both sides of the insertion of the suspensory liga-
ment. The consistency is increased, the elasticity decreased. The
cut surface is ocher-yellowish-brown in color and very dull, as well
as slightly uneven. The vessels contain much dark blood. The wall
of the gall bladder is deep green with black hemorrhagic spots. It
is thickened, oedematous, and almost gelatinous. The viscus con-
tains a moderate amount of thickened, almost black, pitchy bile.
Stomach : The serosa is injected and shows a number of hemor-
rhagic spots. The walls as a whole are thickened. The contents
of this organ consist of a dark cofi'ee-brown, grumous mash. The
mucosa is swollen and all the vessels are injected. The whole sur-
face is studded with small hemorrhagic dots. On the posterior
wall, not far from the pylorus, there is a perfectly smooth cicatrix
with radiating lines; however, this is not at all well marked and
can be seen only on close and careful inspection. There is a fairly
hard nodule, not larger than a pea, in the circumference of the
pylorus; it is not well differentiated from the neighboring tissue,
and shades off gradually. There is no ulceration in the region
of the pylorus and the mucosa above the described nodule shows
no changes beyond congestion, etc. The esophageal and duodenal
mucosa likewise shows great congestion and hemorrhagic spots.
In the large intestine there are found a number of dark, sub-
mucous nodules of the size of a pea; they contain dark, partly
coagulated blood. The intestinal follicles are swollen. The tissues
in the right inguinal region on being cut discharge a considerable
amount of blood-tinged serous fluid. The glands are swollen,
completely hemorrhagic, and generally indistinguishable as to out-
line. The capsules are only exceptionally recognizable, and as a
rule the whole tissue forms one undifferentiated, bloodv mass. The

88

bloody infiltration is extensivelj' continued into the surrounding
tissue. The whole inguinal region is adherent to the overlying
skin. The hemorrhagic condition is continued into the inguinal
canal. The whole chain of glands, the right iliac, the retroperi-
toneal, the abdominal, the aortic, etc., is in a state of hemorrhagic
inflammation. The areolar tissue of the left side of the pelvis and
the abdominal cavity is oedematous, gelatinous, and extensively
infiltrated with blood. The sheaths of some of the pelvic and
abdominal vessels show hemorrhagic infiltration, as does also the
loose tissue around the right kidney and the gall bladder. Except
where specifically mentioned, the glands are all swollen, softened,
and at least highly congested, if not hemorrhagic. Smears from
the right inguinal glands show numerous plague bacilli. The
organisms are also present in moderate numbers in those from the
spleen.

Anatomic diagnosis. — Congestion and oedema of the lungs ; hem-
orrhagic, acute, parenchymatous nephritis; parenchpnatous and
fatty degeneration of the liver; hemorrhagic inflammation of the
right inguinal and many other hiiiph glands; extensive subserous,
submucous, and interstitial hemorrhages. Bubonic ^^lague.

The cultures inoculated at the post-mortem examination devel-
oped a typical growth.

Microscopic examination. — Upon a general survey, the glands of
the right inguinal region show an extensive hemorrhagic infiltra-
tion with much necrosis, particularly in those places where the
extra vasaton is the greatest. The normal gland structure in general
has disappeared, but here and there follicles may still be recognized
where the blood extravasation is not so extensive. All vessels are
much dilated and engorged. The connective tissue at the hilus
is greatly increased. The capsules of the glands are loosened by a
hemorrhagic oedema ; and their cells as well as those of the connective
tissue reticulum of the glands themselves are swollen and even
completely necrotic. The periglandular, loose, areolar tissue is
likewise hemorrhagic and in part distinctly necrotic. If the vessel
walls are examined with a high power, it is seen that they are
rarified by an cedematous infiltration. The cells forming them
either show no nucleus at all or a poorly stained or a pyknotic one.
The same changes are noticeable in the capsular and periglandular
vessels. A number of the parenchyma cells, outside the zone of
the dense bacillar zooglea masses, consist of fairly normal, small

89

mononiiclars. Others of this type show a swollen protoplasm with
either a poorly stained niiclens or one not stained at all. Bodies
are also present which may best be described as cell shadows, which
contain a rather fine, dark broA\'n, grannlar pigment, probably
a hemoglobin derivative. Coarse and fine granular, yellowish-brown
pigment is also seen between the cells. Typical plasma cells,
mononuclears with- a large hyaline protoplasm, and polynuclears are
not numerous. Eosinphiles are not seen. A few small vessels
contain hyaline fibrin thrombi; but there is no extravascular fibrin
reticulum present. Plague bacilli are found in dense masses, in
which only a few autochthonous tissue cells are left and those greatly
changed. From the dense clumps the bacilli infiltrate the spaces
between the cells in those parts of the sections where more cells
are still present. Spleen: The capsule shows no marked changes;
the trabecule, on the other hand, generally show hyaline swelling
and loss of nuclei. A small trace of an original Malpighian body
is seen here and there. Most of the corpuscles have disappeared
in consequence of necrotic processes, or at least their boundaries
have become quite indistinct, the follicle losing itself in a dense
mass of changed nucleated cells and degenerating erythrocytes.
The pulp spaces are indistinguishable on account of their great
engorgement with blood. Everywhere there is present a homo-
geneous mass with vacuoles, which are more or less occupied with
nucleated cells. The homogeneous matrix, which stains well ^vdth
eosin (in some places it takes the stain particularly well), is very
probably a product of degenerated, agglutinated, confluent red
blood corpuscles. In fact, in some places the more or less homo-
geneous, eosin-staining material is undoubtedly composed of red
blood cells. The cells found in the vacuoles of the hemogeneous
matrix are mostly polynuclears. Next in order of frequency come
small mononuclear cells. These show more marked changes than
the former, namely, poorly stained or very pyknotic or fragmented
nuclei. Eosinophiles are also found. Plasma cells and large hyaline
mononuclears are not seen in the spleen. Bacilli in snuill numbers
are scattered all over the sections, and in places are found in more
numerous groups. A few small vessels contain hyaline thrombi.
Kidneys: All vessels are much dilated and engorged. The intersti-
tial connective tissue is oedematous and shows a decided increase in
some places, although not so great as that seen around the capsules
of Bowman. Tn general the glomerular capillaries are like the

90

renal vessels^, much dilated and engorged. Hyaline fibrin thrombi
are fomid in few of the glomeruli. The thrombosis of the glom-
endus is as a rule not complete and only a part of the tuft is closed
by fibrin. The thrombi are sometimes continued into the vasa
afferentia and eff erentia and beyond them. The capsular epitheliimi
shows a minor degree of degenerative, but no proliferative, change.
The tubular epithelium is in a state of cloudy swelling and fatty
degeneration. These degenerative processes are more marked in
the convoluted than in the straight tubules. Most of the uriniferous
canaliculi contain an abundance of granular material, while others
have casts. Sections from the kidneys show an extensive infection
with plague bacilli, which is mostly localized in the glomerular
capillaries. Both in the open and in the thrombosed capillaries
numerous bacilli may be seen in loose groups or sometimes even
in dense masses. In the thrombosed vessels the bacilli are some-
times between the thrombus and the vessel wall. The organisms
occasionally extend beyond the glomerulus into the vasa recta. Here
and there bacilli are found at quite a distance from a glomerulus
and occasionally in the capsular space and in the uriniferous
tubules. Liver: The interacinous tissue shows small, round-cell,
inflammatory foci and increase of the fibrous connective tissue.
The portal and hepatic veins and the interlobular capillaries are
dilated and engorged, showing a somewhat increased number of
leucoc}i;es. The parenchjona cells are very coarsely vacuolated and
contain much bile pigment. Here and there plague bacilli are
found in the capillaries; they appear in larger, denser groups
near the central vein of the lobule and near the interlobular inflam-
matory foci. Where the bacilli are present extensivel}', there are
seen cells with one, two, or three nuclei with many bacilli included
in their protoplasm. These phagocytic cells appear to be vascular
or lymphatic endothelial cells. Lungs : All vessels, including the
interalveolar capillaries, are much dilated and engorged. The
alveoli are partly or completely filled vdth a granular, or almost
homogeneous, eosin-staining material; they also contain quite a
few desquamated, pigment-filled epithelial cells. Here and there
extravasated blood is found in the air spaces. Fibrin is not visible
in the pulmonary sections, nor are plague bacilli found. Stomach :
The interglandular capillaries of the mucosa are greatly dilated,
and free blood is observed between the glands. Towards the surface
of the mucosa the hemorrhagic areas become larger. The most

91

superficial parts of the mucosa, which are strongly infiltrated with
blood, are necrotic. Here we find places where the surface epithe-
lium is missing, so that the blood is free on the surface of the
mucosa. The large parietal cells are very coarsely granular and
stain deeply with eosin. Some of them have two or three nuclei,
while others are much swollen and have lost their nuclei. Fairly
dense masses of plague bacilli are found in some of the superficial
hemorrhagic areas. The nodule in the region of the pylorus of
the stomach shows a mucosa in an extensive state of glandular
hypertrophy. The gland formation, however, is so typical that the
process cannot be looked upon as an early stage of carcinoma. It
is simply a glandular hypertrophy. In the duodenum the same
vascular changes are seen as in the gastric mucosa. However, the
blood extravasation is very insignificant and the vascular dilatation
more moderate. In spite of this, the more superficial parts of
the duodenal mucosa is necrotic, not uniformly so but in small
patches. Eosinophilic polynuclear are numerous in the duodenal
mucosa and submucosa. Plague bacilli are not found. The
dark cysts encountered in the interior of the large intestine
are blood cysts formed between the muscularis and the submucosa
of the bowel. The hemorrhage has completly dissected apart the
muscularis and the submucosa. The contents of the cysts are pale,
changed, or fairly normal erythrocytes, between which are found
hyaline degenerated vessel walls and some irregularly distributed
elastic fibers. The mucosa overlying the cysts is in a condition of
coagulation necrosis. Plague bacilli are not found in or near these
blood cysts; neither are any animal parasites encountered.

Case No. 13. Left Sxjbmentajl Bubo.

[Necropsy Protocol No. 1027. F. C, a Filipina, 14 years old, from No. 195 Plaza
Leon XIII, Tondo. Died after a short illness of unknown duration, on Sep-
tember 7, 1904, at 7.10 o'clock p. m. Post-mortem examination made on
September 8, at 3 o'clock p. m.]

The body of a slender young girl about 15 years of age. Mam-
mary glands fairly well developed and the pubes scantily covered
with hair. The nutrition is good. There are no deformities,
external wounds, sores, pustules, etc. The post-mortem rigidity
is fairly strong ; the post-mortem lividity is well marked on depend-
ent parts and spreads toward the sides of the trunk. The left
side of the face is quite cyanotic and swollen. The swelling is
most marked underneath the parotid region; it is not sharply

92

defined but shades off gradually into the surrounding tissues. The
swollen area is oedeniatous and doughy to the touch. The enlarged
glands can not be distinguished well by palpation. The abdominal
cavity contains a small amount of fluid. The lungs are nowhere
adherent. The pericardium is normal, as is also the pericardial
fluid. The right ventricle of the heart is well contracted, the
left one dilated. A few small subepicardial hemorrhages are.
found on the surface. The myocardium is fairly firm, pink with
a very faint tinge of yellow and somewhat dull in appearance.
Otherwise the heart and the large vessels are normal. The coronary
vessels are much congested, the two sides containing chicken-fat
clots and some dark, fluid blood. The lungs are inflated, heav}^,
and bluish-purple on the outer surfaces. The right lung shows
a number of small subpleuritic hemorrhagic spots, most of which
are found at the two adjoining surfaces of the middle and the
lower lobes. On section the pulmonary tissue is found to be much
congested and oedematous and dark brownish-red. The bronchi
contain some foamy, viscid mucus and their mucosa is slightly swol-
len and injected. The injection of the bronchial mucosa is very
marked and the small arteries and veins are quite visible. The
mucosa of the larynx is in a similar condition. The internal
surface of the epiglottis exhibits al^out half a dozen pin-head-sized
submucous hemorrhages. The In'onchial glands are quite markedly
enlarged, softened, and congested, those on the right side being
more so than the ones on the left. Posteriorly at about the middle
of the trachse there are found two lymph glands each of the size
of a bean, which are swollen, soft, and much congested. The left
tonsil is swollen, hyperemic, and slightly ulcerated. The spleen is
about one and one-half to two times the size of the normal adult
spleen. Externally it is bluish-gray and has a smooth capsule. In
consistency it is quite soft and flabby. On section the surface is
granular and the pulp is found to be very soft. The trabeculge
are distinct; the follicles are very indistinct. Much brown juice
can be scraped from the surface. The kidneys are quite large and
fairly firm. The capsules are smooth, and the external color is
pinkish-gray. Both kidneys show a few subcapsular hemorrhagic
spots, the largest one being of the size of a split pea. The capsules
peel off easily. On section the siirface is quite dull and grayish-
yellow, with injected blood vessels, which have a prominent
yellowish-gray background. The glomeruli are visible as rea

93

points. The pyramids are rather pale. The relation of" the cortex
to the medulla is normal. The pelves are injected but without
hemorrhagic spots. The right ureter is somewhat dilated and
about one and one-half times the diameter of the left one, which
is normal in size. The bladder contains about two ounces of turbid,
3'ellow urine. The mucosa of the bladder and the ureters is
hyperemic but not hemorrhagic. The ovaries, the tubes, and the
uterus are normal. There are no fresh corpora lutea, but the
uterine mucosa is diffusely hemorrhagic. The serosa of the corpus
^nd the tubes shows dilated and congested vessels. The suprarenale
are dark brownish-yellow, fairly soft, somewhat swollen, congested,
and oedematous. The gastric and duodenal mucosa is enormously
congested, the former showing extensive hemorrhages in the form
of denselv crowded dots and irregular areas which have evidentlv
been formed by petechias and ecchymoses which have become con-
fluent. The submucous hemorrhages in the duodenum are moderate
in extent. The mucosa of the small as well as of the large intestine
shows a marked hyperemia, but the lymph follicles are not swollen
or at most very moderately. The mesenteric and retroperitoneal
glands show only very moderate swelling and congestion. The
liver is of normal size. The capsule is smooth and purplish-blue
with grayish-yellow mottling. The consistency is perhaps somewhat
increased. On section the surface is even and yellowish-pinkish-
broAvn. The distended veins of the liver contain much blood. In
the center of the right lobe there was found a focus the size of a
pea, composed of a somewhat loose, soft, grayish-white mass. The
gall bladder is normal and contains some dark greenish-yellow bile.
The ducts are normal. The pancreas is slightly swollen but other-
wise normal. When the swollen region of the left side of the face
is incised, a yellowish serous fluid escapes from the areolar sub-
cutaneous connective tissue. The skin is firmly adherent to this
tissue and can be dissected only with some difficulty. The color
of the serous fluid is yellowish with a faint tinge of red. On
dissecting deeper into the tissue, enlarged lymph glands are encoun-
tered, which are swollen, soft, and much congested. Glands are
met with deeper down which are intensely so. The hemorrhages,
however, do not extend into the oedematous periglandular tissue.
The parotid gland is swollen and much congested, but not hemor-
rhagic. Brain: The longitudinal sinus contains a large chicken-
fat clot. The pial vessels both on the convexity and at the base

94

are enormously congested. The brain substance shows many hemor-
rhagic points (small hyperemia vessels) ; otherwise no noteworthy
changes are seen.

Anatomic diagnosis. — Congestion and parenchymatous degenera-
tion of the kidnej^s; congestion and oedema of the lungs; one
necrotic focus of the liver with congestion and fatty degeneration;
multiple subserous and submucous hemorrhages; left submental
hemorrhagic bubo. Bubonic plague.

Smears from the deep hemorrhagic submental glands show many
typical plague bacilli; while those from the superficial, softened,
and congested glands reveal only a very moderate number. In
the juice of the spleen there are very few, and in that of the lungs
they are exceedingly scanty. Culture tubes inoculated from the
hemorrhagic glands and from the spleen developed a typical growth.

Microscopic examination. — Sections from the deep submental
glands show a complete loss of the finer structure, extensive free
hemorrhages, and the formation of a homogeneous eosin-staining
material (evidently derived from degenerated blood corpuscles
which have become confluent, and extensive areas of necrotic
material. In the latter there are a few cells with pyknotic nuclei.
Vessels are still recognizable in this necrotic mass, but merely by
faint outlines, the greatly dilated walls having become much
thinned and loosened. The capsule has been loosened by a cellular
infiltration comjoosed of mononuclear and polynuclear leucocytes.
The infiltration extends beyond the capsule into the loose, periglan-
dular, areolar tissue. In the outer part of the gland, the cells
are better preserved and the hemorrhagic extravasation is moderate.
The cells found here, aside from erythrocytes, are mononuclears
and a few polynuclears. The former are mostly of the small type,
although there are some large ones, with a vesicular nucleus
containing a reticular chromatin and a large body which has a
marked afiinity for methylene blue. Bacilli are found irregularly
diffused throughout the gland; they are very poorly stained, shell-
like, and oval. The more superficial cervical glands are fairly well
preserved in structure, showing an increase of the hilum connective
tissue, great dilatation of the otherwise intact vessels, very small,
scanty areas of blood extravasation, and large mononuclears with
a somewhat basophilic protoplasm. Bacilli are present in very
scanty numbers. No fibrin thrombi or fibrin networks are found
in any of the glands. The spleen shows small, not well defined

95

corpuscles and indistinct pulp spaces crowled with red blood cor-
puscles and nucleated cells. Most of the latter are small mononu-
clears. Large mononuclear, hnrnphatic endothelia are not very
numerous, a few of them containing the remnants of red blood
corpuscles. A moderate number of plague bacilli are present in the
sections. The vessels of the kidneys, including the glomerular
capillaries, are greatly engorged and small areas of blood extravasa-
tion, both subcapsular and interstitial, are seen here and there.
The uriniferous tubules show a loss of epithelium and advanced
cloudy swelling with granular material in the tubular lumina.
The capsules of Bowman are not thickened. There is no prolifera-
tion of the glomerular epithelium. The interstitial connective
tissue is cedematous and here and there shows 'some finely granular
material deposited between the tubules. Plague bacilli are not
seen in the renal sections. The suprarenals show an enormous
engorgement of the interfascicular capillaries. In the liver one
sees great dilatation of the capillaries, and veins with an increased
number of leucocytes in the former. The parenchyma cells are
both finely and coarsely vacuolated. One of the three pieces of
of liver which was taken for microscopic examination shows a
very small focus of coagulation necrosis. Here the parenchyma
cells are completely necrotic and in fact indistinguishable. A few
small mononuclears are found scattered over the necrotic focus,
which also shows a reticular, finely fibrillar matrix. At the very
margin of the focus is seen a .multinuclear giant cell, with a
crescentic arrangement of its nuclei. The large cell has the
typical appearance of a giant cell in tuberculosis. There are also
encountered in this area a very few cells approaching the type of
the epithelioid cells of the bacillar tubercle. The larger necrotic
focus found in the center of the right lobe likewise consists of
cells in a state of complete coagulation necrosis and finely granular
material. At the periphery of the mass there is a zone of cellular
infiltration composed of small lymphoid cells, mixed with consider-
able numbers of ordinary pohTiuclears. Eosinophiles are not seen.
In the interior of the necrotic mass there are found a number of
reticula of typical fibrin which gives Weigert's reaction. It is in
connection with this fibrin and in its neighborhood that great
numbers of shell-like plague bacilli are encountered. No plague
bacilli are found in other parts of the hepatic sections. Neither
in the small tubercle nor in the larger necrotic focus could any

9()

tubercle bacilli be demonstrated. In the lungs the vessels are
dilated and the alveoli are mostly open, some of them containing
desquamated epithelia, others fairly numerous red blood corpuscles,
and still others a hyaline or finely granular material, evidently the
product of an cedematous fluid, coagulated by the fixing and harden-
ing liquid. No plague bacilli are found in the pulmonary sections.
The gastric vessels are dilated and greatly engorged. Much blood
extravasation has taken place from the intergiandular capillaries.
The petechia and ecchymoses are in the outermost layer of the
mucosa and often separated from the surface only by a thin remnant
of tissue. The other zone of the mucosa towards the free surface
is necrotic and its cells are swollen and have lost their nuclei.
Numerous plasma mast cells are seen in the submucosa. Plague
bacilli do not appear in the areas of blood extra\'«sation, nor any-
where else in the stomach wall.

Case No. 14. Right Cervical Bubo with Secondary Plague

Septicopyemia.

[Necropsy Protocol No. 889. E. J., Filipino, male. 63 years old, from No. 142
Caballeros Street, San Nicolas District. Died February 18, 1904, at 1 o'clock
p. m. Sick five days ; cause of death unknown. Post-mortem examination made
February 19 at 8.45 o'clock a. m., about twenty hours after death.]

The body of a native well advanced in 3^ears; hair gray. Post-
mortem rigidity still fairly well marked, but beginning to disap-
pear. The post-mortem lividity is pronounced on dependent parts
and spreads toward the sides and interior surfaces of the body.
The integument shows no injuries or sores. There are no buboes
externally visible in the inguinal, cervical, or any other region.
The abdomen is slightly distended. On section some dark, fluid
blood escapes from the severed veins. The peritoneal and pleural
cavities contain a small amount of serous fluid, the serous mem-
branes are somewhat dull and their vessels markedly injected.
The pericardium contains a small amount of clear fluid. The
heart muscle is soft and flabby; the left ventricle is moderately
contracted, and the right one dilated. The external surface shows
a number of small irregularly distributed subepicardial petechiae.
The myocardium is pinkish-yellow. The valves are nonnal. The
arch of the aorta is atheromatous. Lungs : Both apices are adher-
ent, the adhesions being firm and fibrous. Externally the lungs are
dark purplish-blue in color; on section they are dark purplish-
brown. They are rich in dark, fluid blood, but do not contain much

97

air. The bronchi show a swollen and congested mucosa, and con-
tain a moderate amount of viscid mucus. The mucosa of the
trachea and larj'nx is congested, particularly that of the epiglottis.
The spleen is small and its capsule slightly wrinkled and rather
soft in consistency. On section the trabeculse are well marked, the
Malpighian bodies are indistinguishable and the soft pulp soft and
dark brownish-red. The kidneys are normal in size; their capsules
are smooth, rather dull, and purplish-blue. On section the surface
is grayish-white, and the vessels considerably injected -and
prominent. The mucosa of the pelves is smooth and-hyperemic.
Liver : The capsule is smooth and purplish-blue with some grayish-
white. On section the veins discharge a good deal of blood; the
surface is smooth and dull brownish-yellow. Here and there a
pale gra}^ soft necrotic focus of small size is seen. The gall
bladder and ducts are normal. The gastric and intestinal mucosa
is hyperemic, the former showing a moderate number of small
hemorrhagic spots. The lymph glands in general are not much
changed, except the right superficial cervical glands, which are
swollen, soft, oedematous, and highly congested, but not diffusely
hemorrhagic.

Anatomical diagnosis. — Congestion and oedema of the lungs;
congestion and parenchymatous degeneration of the kidneys; sub-
serous and submucous hemorrhages; right cervical bubo. Plague.

Smears from the cervical glands of the right side show numerous
plague bacilli as well as numerous delicate, small streptococci.
Culture tubes inoculated from the cervical glands and from the
spleen developed a typical plague growth. No streptococci were
found in the cultures.

Microscopic examinations. — The capsule of the cervical glands is
thickened, and the connective tissue at the hilum much increased.
The vessels of the capsule and the hilum are dilated and much con-
gested. The entire substance of the glands is traversed by dilated,
densely filled vessels; the differentiation into follicles is almost
completely lost, the medullar}^ cords are no longer distinguishable.
The peripheral Ijonph sinus is dilated and contains a number of
mononuclear cells and a good deal of granular material. The
blood vessels, though dilated and much congested, show no marked
changes in their walls, except some thickening of the adventitia;
they do not contain any fibrin but are densely crowded with
25483 7

98

erythrocytes, and show an increased number of leucocytes. The
cells of the lymphatic tissue proper consist of small mononu-
clears of the ordinary type and a considerable number of plasma
mast cells. Eosinophiles are not seen. Great numbers of plague
bacilli are found in the lymph sinus, in the other distinct lymph
channels, vessels, and clefts and all over the gland substance. The
interior of the most of the blood vessels generally is free from
bacilli, although some of the vascular lumina show these organisms
in considerable numbers. Gram's stain shows no streptococci in
this gland, though smears made from the cervical glands at the
post-mortem examination contain typical streptococci. Spleen:
The trabecule and the walls of the splenic arteries are thickened;
some of the Malpighian corpuscles are still recognizable, although
most of them can no longer be distinguished, even those which
are preserved being quite small. In general, corpuscles and pulp
form one almost structureless mass consisting of a large number
of red blood corpuscles and mono- and polynuclear cells. The
original pulp spaces can no longer be outlined, and all of the
splenic tissue is profusely infiltrated with plague bacilli; however,
these are not found in large solid masses, as in the lymph glands,
but in small groups. The kidneys show profound parenchymatous
degeneration. The lining epithelia of the convoluted tubules have
generally lost their nuclei ; the cells as a whole are much swollen and
indistinct in outline; and the tubular lumina are more or less
obliterated by granular material. The straight tuliules show the
same changes, though to a much less degree. The glomeruli do not
show such profound changes, and are fairly normal in appearance,
though quite a number of plague bacilli are found in some of them.
However, these organisms are located, as it appears, not in the
glomerular capillaries but between the loops of the tufts. The
lymph clefts between the tubules likewise contain plague bacilli,
but in moderate numbers only. The liver shows some very small
interlobular inflammator}' foci composed of small round cells, and
here and there some increase in fibrous connective tissue around
the interlobular vessels and bile ducts. The parenchyma cells are
finely vacuolated. The capillaries are rather distended but not
well filled with blood. In general the hepatic capillaries show
very few plague bacilli, except in some places — i. e., those cor-
responding to the necrotic foci seen at the autopsy, where we find
enormous sausage-like masses of these organisms. They are located

99

in the capillar}- lumen, none being seen inside the cells. The
parench3'ma cells in the neighborhood of these bacterial emboli
show evidence of necrobiosis (poorly stained nuclei, etc.). The
pulmonary tissue exliibits alveoli partly filled with desquamated,
pigment-containing alveolar epithelia, and granular material, while
here and there ma}' be seen an air space almost completely filled
with blood. The interalveolar capillaries and the other pulmonary
blood vessels are much congested and densely filled with blood.
Quite a few plague bacilli are found in the interalveolar con-
nective tissue. It appears that these organisms are located inside
the epithelial cells lining the l}Tnph clefts, some also being found
inside the alveolar epithelia. Xone are found in the pulmonary
blood vessels. The alveoli show the presence of a small number
of large, slender bacilli, which, like the organisms of plague, are
decolorized by Gram's method.

Case No. 15. Right Axillary BtrBo.

[Necropsy Protocol No. 973. F. A., Filipino, male, age 28 years, from 661 Calle
Bllibid, Santa Cruz ; died May 9, 1904, at 11 o'clock p. m. Post-mortem exam-
ination made fifteen hours after death.]

The body of a strong, well-developed man between 25 and 30
years of age. Nutrition is good. Post-mortem rigidity is marked ;
post-mortem lividity is well developed. Near the right nipple
there are seen two dried-up vesicles, which are completely collapsed
and covered with dry epidermal scales. Otherwise there are no
open wounds on the body. The right axillar}^ lymphatics form a
flat doughy mass of the size of the palm of the hand. The swelling
in the right axillar}' space is not well defined but gradually shades
off into the surrounding tissue; the skin overlying this region is
very cyanotic. On being cut the mass is found to be very cedematous
and it first discharges a blood-tinged serum and then a bloody
fluid. Xo individual glands can be mapped out, but everything is
completely infiltrated by a hemorrhagic exudate. The latter is
continued into the deep fascia of the thorax and the pectoral
muscles, finally reaching the intercostal muscles and penetrating
into the thorax. The inguinal, cervical, and cubital glands are all to
a certain extent palpable, and, when dissected out, are found to be
somewhat enlarged, softened, and congested. On opening the
body cavities the serous membranes are seen to be congested and
rather dull. The serous fluid in the abdominal and thoracic
cavities is not increased. The right lung has formed a few slight

100

adhesions. On the right side there is found an area of subpleural
hemorrhage^ which forms a direct continuation of the ones radiat-
ing from the axillary bubo. The lungs are in general normal in
form, fairly well inflated, and purplish-blue in color, with a few
small subpleural hemorrhages. The pulmonary tissues are con-
gested and oedematous. The mucous membrane of the trachea, the
bronchi, and the larynx is somewhat swollen and highly congested.
The heart is normal in size. The coronary vessels and their
branches are much engorged. A few subepicardial hemorrhages
are found on the anterior surface. The myocardium is rather soft
and flabby and pinkish-yellow in color. Otherwise the heart is
normal. The spleen is twice its normal size, quite soft, steel-gray
externally, and reddish-brown on section. The pulp is quite soft.
The trabeculse are well marked, the Malpighian bodies less so. The
liver is normal in size, though somewhat increased in consistency.
It is purplish-blue in color with some grayish-white mottlings. On
section it is found to be much congested. The gall bladder is
normal, containing a large amount of yellow, thin bile. The
kidneys are normal in size, smooth, bluish-purple externally, and
yellowish-pink on the cut surface. The pelves are much injected,
that of the left kidney containing a small amount of extravasated
blood. The adrenals are normal in size, of fair consistency, and
brownish-yellow in color. The mucosa of the stomach shows numer-
ous small hemorrhagic spots, which are also seen in moderate
numbers in the duodenal mucosa. The lymphatics of both the
large and the small intestine are somewhat swollen.

Anatomic diagnosis. — Congestion and oedema of the lungs ; paren-
chymatous degeneration of the kidneys; right axillary hemorrhagic
bubo; general swelling, hypertrophy, and congestion of the lymph
glands. Bubonic plague.

Smears made from the different organs show plague bacilli,
which are present in considerable numbers, together with some
diplococci in those from the axillary hemorrhagic bubo, and in
fair numbers in the left inguinal glands and in the liver, while
in the spleen they are plentiful. The cultures developed typical
plague bacilli, but all were contaminated.

Microscopic examination. — The right axillary glands show an
almost complete necrosis with a loss of all the finer details of
structure and an intense hemorrhagic infiltration, which extends
into the surrounding tissue. A considerable number of very poorly

101

staining plague bacilli are seen in the sections. The inguinal
glands exhibit an increase of connective tissue at the hilus, great
cedema, general vascular dilatation, and engorgement with hyaline
degeneration of the rarefied vessel walls. A moderate number of
plague bacilli are present in the inguinal glands. In the spleen
the Malpighian corpuscles are small and the pulp spaces are not
very distinct, being crowded with many poljiiuclears. The erythro-
cytes are only moderately numerous. The lymphatic endothelia of
the pulp spaces have proliferated to a moderate extent, some of them
showing two or three nuclei. The splenic sections contain innum-
erable plague bacilli; however, they are not present in such solid
zoogloeal masses as are frequently seen in primary buboes, but in very
dense groups consisting of many hundreds of bacilli, between which
the tissue cells are only sparingly seen. This condition is most
marked in the peripheral lymph sinus. In the pulp spaces the
bacilli are less numerous, though present to a large extent. A great
condensation of bacillar masses is also seen at the peripheries of
some of the Malpighian corpuscles, while their interior is almost
entirely free from microbic invasion. Phagocytic cells containing
bacteria are not seen in the spleen. The kidneys show a most pro-
found degree of cloudy swelling of the tubular epithelia, with the
presence of much granular material and some hyaline casts. All the
vessels are much dilated and engorged, particularly the glomerular
capillaries. Here and there in the glomeruli an incomplete fibrin
thrombosis is met with. Groups of plague bacilli are found in
the glomerular and intertubular vessels, some of them amounting
to fairly dense masses of bacteria. A very few isolated bacilli are
seen here and there in the uriniferous tubules. The hepatic sec-
tions exhibit veins and capillaries much dilated and engorged with
an increased number of leucocytes. The parenchyma cells are
vacuolated and coarsely granular, their nuclei often being poorly
stained and even lost. The capillaries show small, loose groups of
plague bacilli, but nowhere a complete occlusion by dense bacillar
masses, as seen in other cases of bubonic plague, with metastatic
bacterial emboli of the liver. In the pulmonary sections the veins
and the interalveolar capillaries are greatly dilated, and the latter
here and there contain small, loose groups of plague bacilli. Very
few single bacilli are seen in the alveoli. Here and there they are
in contact with the wall, so that their derivation from the intracapil-
lary groups is probable.

102

GROUP III. PRIMARY BUBONIC PLAGUE WITH SECONDARY

PLAGUE PNEUMONIA.

Case No. IC. Asibulatory Plague, ob Pestis Minor.

It has been known for many years, long before the specific bacillus
had been discovered, that plague cases exist in which the symptoms
are very mild and in which the patient may be free from any
marked elevation of temperature. These have been called ambu-
latory plague or pestis minor and have quite properly been compared
to typhus ambulatoria.

Griesinger, Liebermeister, Montague-Lubbock, Manson, Scheube, and
others have called attention to the fact that such ambulatory cases, in
spite of the mild character of their symptoms, are liable to sudden collapse
and fatal termination. Manson (Tropical Diseases, 3d edition, London,
1903, p. 249) speaks of this type as abortive or larval plague, and states
that certain epidemics are distinguished by a larger proportion of mild
cases. "In such," he says, "buboes form and suppurate or resolve, the
associated constitutional symptoms are comparatively mild or perhaps
altogether wanting. In every epidemic there may be cases in which
the patient is able to be about, having little, if any, fever, and apparently
being little inconvenienced by the disease. Such cases, however, may
collapse suddenly."

However, there is very little to be found in literature showing that a
more careful investigation of this type of cases has been made. So scanty
is our knowledge that the extensive report of the Indian Plague Com-
mission has no more to say about the pathology of pestis minor than
the following (Vol. V, p. 432) : "Death from pestis minor probably never
occurs, but, at any rate, no description of the pathology of plague deals
with this type."

The case to be rejDorted as an example of ambulatory plague
demonstrates that the term "pestis minor" is a misnomer, when
applied to such "walking-plague patients" as die suddenly. In
our case the necropsy and the microscopic examinations furnished
evidence sufficient to account for the unexpected death in the
absence of any marked previous subjective symptoms of ill health.
The history and the findings in this case, which is somewhat com-
plicated by a simultaneous, evidently very recent^ tuberculosis of
the lungs, were as follows :

The death of a Filipino lad, 17 years old, was reported to the
Santa Cruz board of health station, Manila, P. I., on February
27, 1904, at 11 o'clock a. m. The body of the deceased was found
in a dimly lighted loft in the corner of a lower unpaved room,
adjoining a soda-water factory at No. 185 Calle Misericordia. On

103

examination nothing worthy of note was seen, except enlargement
of the glands in the inguinal region and Scarpa's triangle on both
sides, as well as a chronic skin affection of both legs. The position
of the body had been changed since death. The boy had been
emploj'ed for general purposes about the place for from four to
five months, during which time he appeared to be in good health,
except that for some weeks before his death his face was rather
pale, and he did not sleep very well. He spent the evening of
February 26 playing in the street with other boys until 11 o'clock,
when he went to bed. About 13 o'clock he awoke, complaining of
pain in the chest and difficulty in breathing. His condition soon
became alarming, and a native physician was sent for, who was
unable to do anything for him. At 2 o'clock he was dead.
(History furnished by district medical inspector, Dr. Terry, of
the Board of Health.)^

Case Xo. 16. Ambulatoey Plague. TEEiiiNATiifG by Embolism of the

PxjLMONABY Artery.

[Necropsy Protocol No. 901.]

Post-mortem examination made on February 27, 1904, at 3
o'clock p. m. The body of a Filipino bo}', about 17 to 18 years of
age and well developed. Post-mortem rigidity strongly marked;
post-mortem lividity prominent on dependent parts and extending
over the sides of the trunk and neck as well as over the anterior
surface of the latter. A greenish-brown, foamy, ill-smelling fluid
oozes from the anterior nares. The anterior surface of the lower
extremities, from the ankles upward to about midway between the
knees and Pupart's ligaments, is covered with a vesiculo-pustular
eruption. The lowermost portions of this eruption consists of
shallow ulcerations covered with brownish, bloody scabs. The
skin lesions higher upon the thigh are still purely vesicular and
the collopsed vesicles are covered with epidermal scales. The
chain of l}Tnph nodes below Pupart's ligaments on both sides is
swollen, the most marked swelling being found in the lowermost
glands on each side. The swollen region is soft and doughy. How-
ever, no fluctuations are noticeable. On incision of the skin the
superficial veins discharge a rather small amount of dark, fluid
blood. The pericardium is smooth and normal, and contains a small
amount of clear, straw-colored fluid. The visceral layer of the
pericardium shows dilated and congested veins. On the posterior

104

surface^ over the left auriculo-ventricular zone two or three dozen
hemorrhagic areas are seen, varying in size from a pin-head to a
millet seed. Otherwise the visceral pericardium is normal. Heart:
The myocardium is fairly firm and somewhat pale. The left
ventricle is contracted, and the right one dilated. The latter con-
tains a rather firm, though somewhat gelatinous, reddish-gray
coagulum, which does not completely fill the ventricular cavity.
The coagulum is continued into the pulmonary artery, which it
completely fills. Here it is firmer in consistency and decidedly
more grayish in color. These variations from the consistency and
color of the clot in the heart became greater the farther the dis-
tance from the entrance of the pulmonary artery to the interior
of the ventricle. The thrombus extends into the main branches
of the pulmonary artery, from where it can be followed into the
lower, secondary branch of the right side, and it is then lost in
the highly congested lower lobe of the right lung. A distinctly
hardened infarcted area can not be found. The blood in the left
ventricle and auricle is fluid and of a dark purple color. The lungs
are quite firmly adherent to the parietal pleura. The lower lobe
of the right lung is particularly firmly adherent to the diaphragm.
The partly obliterated pleural sacs contain a small amount of
slightly turbid, yellowish fluid. The upper lobes are dark grayish-
pink and contain a considerable amount of air; the lower lobes,
particularly the right one, are dark purplish-blue and contain
very little air. On section the lower lobes are found to be quite
cedematous and filled with a very dark, purplish, fluid blood, which
oozes out freely from the larger and smaller vessels. The right
lower lobe on the cut surface shows some small, grayish-white dots.
The bronchi contain a small amount of foamy, grayish-white fluid.
Their mucous membrances are injected and rather bright-red in
color. The trachea and the larynx likewise show swollen, injected
mucosa. The spleen is large and bluish-pink in color, its capsule
smooth and shining. The cut surface is dark purplish-brown. The
trabecule and the Malpighian corpuscles are distinct. The pulp
is fairly firm in consistency. The kidneys are rather small and
their surface smooth and of a dark grayish-pink color. The
capsules peel off easily, and the denuded surfaces then show the
small vessels to be much injected. They stand out plainly on a
grayish-yellow background. On section the vasa recta and the
glomeruli appear quite strongly injected and intensely scarlet.

105

The tubules are quite markedly yellowish-gray, the surface on the
whole being rather dull. The pyramids are purplish. The mucous
membrane of the pelves is smooth and somewhat congested. Liver :
The capsule is smooth, shining, transparent, and pinkish-gray in
color, some areas being decidedly mottled. The cut surface shows
the center of the lobules to be grayish-white ; they are distinct in
outline. The surface as a whole is dull. The veins contain much
dark, fluid blood. The gall bladder contains some turbid, greenish-
yellow bile, its mucous membrane being smooth. There are no
stones; the ducts are normal. The stomach and intestines appear
fairly normal. The suprarenals and the' pancreas are normal.
The inguinal glands on both sides are enlarged, swollen, soft, and
rather bluish-pink in color. On section they show injected vessels,
which stand out prominently on a grayish-yellow background. The
substance of the glands is soft. No abscess formation has occurred.
An abundant, grayish-white fluid can be scraped from the cut
surface. The lower glands of the chains on each side are the
largest, showing a central softening quite markedly. There is,
however, no abscess formation. These glands are equal in size on
both sides and measure 4.8 by 3.7 by 1.7 centimeters. The
mesenteric, the cervical, and the other glands examined are all
moderately enlarged and more or less congested. Marked congestion
exists in the bronchial glands.

Anatomical diagnosis. — Congestion and oedema of the lungs;
parench}Tnatous degeneration of the kidneys; embolism of the
pulmonary artery; inguinal buboes. Plague.

Smears were made during the post-mortem examination from
the liver, the spleen, and the glands. In the smears from the
spleen and the glands only a very small number of bacilli are
found. They are more numerous in those from the liver. Some of
the bacilli found in the latter are quite typical in appearance,
showing polar staining and rounded ends. Other bacilli are
swollen, somewhat irregular, and approaching the type of the invo-
lution forms seen on artificial media. Still others are small and
look decidedly like diplococci. Others form small chains, the
individual members of which appear to be in a state of partial
dissolution. The cultures inoculated from the organs developed
typical plague bacilli.

Microscopic examination. — Liver: The liver shows extensive
interlobular, inflammatory foci, formed by a cellular exudate.

106

The infiltrating- cells are found around the interlobular arteries,
veins, and small bile duets. The small interlobular vessels show
a marked thickening of the adventitia, and most of the lumina are
found to be surrounded by a number of concentric rings, com-
posed of delicate connective tissue fibers. Occasionally there is
found a small vessel entirely occluded by an obliterating pro-
liferation of the lining endothelium. The cellular exudate of the
inflammatory foci consists of lymphoid cells and a high per-
centage of eosinophilic polynuclears. In some places the latter form
one-fourth to one-fifth of the total number of infiltrating cells.
Plasma cells are very sparingly represented. While this descrip-
tion conforms in general to most of the inflammatory foci in the
liver, other areas present decidedly varied appearances. In these
the foci, which are more or less nearly circular, clearly show a center
consisting of epithelioid cells with a vesicular nucleus and a large
protoplasmic body. Multinuclear giant cells are found in some
of the nodules. The histology of these round or oval nodules is
clearly that of the bacillar tubercle. The nodules also show a fine,
concentrically arranged, fibrillar network of connective tissue fibers.
Regressive changes are not seen. There is no caseation, nor does
Weigert's stain show any fibrin. The histology of the small
tubercules in the liver, and it may here he added that of the similar
structures found in the lungs, is identical with what has recently
again been described by Baumgarten as being the structure of
the tubercle experimentally produced and about two or three
weeks old, which has not yet undergone any regressive changes,
but in which the appearance of the first giant cells indicates that
the prolifieration of the tubercle bacillus, as well as that of the
inflammatory cells, has come to a standstill. Baumgarten also
describes the occlusion of small vessels by endothelial proliferation
brought about by the presence of the tubercle bacillus. The nodules
in the liver as well as those in the lungs contain an element which
is foreign to the typical uncomplicated tubercle, namely, numerous
eosinophilic polynuclears. It is impossible to prove the presence
of tubercle bacilli, but the tubercles are found to be infected with
the organisms of plague. The latter are seen here and there in
both types of inflammatory foci, in those which simply show the
structure of an ordinary inflammatory area, and in those possessing
the features of a bacillar tubercle. The parenchyma cells of the
liver exhibit a moderate degree of fatty degeneration. The capil-

107

laries are well filled with blood. Lungs: Section from the right
lower lobe show a great engorgement of the interalveolar capillaries ;
in fact, all the blood vessels are highly congested. The alveoli
present a varying picture ; some of them are open, having contained
air only, and others are filled with extravasated blood, which does
not show any degenerative changes. Desquamated alveolar epi-
thelia, containing hematoidin granules, are seen occasionally. The
imchanged character of the blood, the small amount of pigment-
containing alveolar epithelia, and the absence of areas of coagula-
tion necrosis, show that the blood extravasation must be of com-
paratively recent in date. Quite a few of the air spaces are filled
with homogeneous coagulated material, which stains deeply with
eosin. Other alveoli contain a lighter staining material. Neither
the homogeneous nor the granular material takes Weigert's fibrin
stain, nor do the capillaries contain any hyaline (fibrin) thrombi.
Here and there is found a small solid nodule, hardly greater in
size than the larger alveoli themselves. These nodules are com-
posed of epithelioid and lymphoid cells and a considerable number
of eosinophilic polynuclears. Multinuclear giant cells are likewise
found in or near the center of some of the nodules. In fact, the
latter are absolutely identical in their make-up with the tubercles
which may be seen in sectioiis of the hepatic tissue. Both in the
pulmonary and in the hepatic tissue neighboring nodules are found,
the peripheries of which are in contact with each other. However,
the individual nodules have not become confluent and their out-
lines are well preserved. It is impossible to demonstrate tubercle
bacilli in these nodules, but they show a small number of the
bacilli of plague, found scattered between the cells. In properly
stained sections it is seen that some of the alveoli contain enormous
numbers of plague bacilli, such air spaces appearing almost filled
with them. Small groups of scattered plague organisms can be
found throughout the sections. Inguinal lymph nodes : The ingui-
nal lymph nodes show numerous large, dilated vessels, replete with
blood corpuscles. Around the larger vessels, particularly of the
hilus vessels, there is a powerful development of the connective
tissue. The general fibrillar connective tissue reticuhun is every-
where much increased. The peripheral follicles generally show a
well differentiated proliferation center. The peripheral lymph
sinus and its branches are dilated. Eosinophilic polynuclears are
found throughout the tissues, though nowhere in such large numbers

108

as in the lungs and liver. Bacilli are seen but sparingly in the
sections. Kidneys: Sections of the renal tissues show practically
normal glomeruli, moderate parenchymatous changes in the tubular
epithelium, and highly congested vessels.

The noteworthy features of this case are its ambulatory nature,
its sudden termination by embolism of the pulmonary artery, and its
complication with what undoubtedly appears to be a very recent
tuberculosis. According to Scheube tuberculosis is a very grave
complication of plague; and Pearse likewise considers it a very
unfavorable factor in this disease. It is very probable that in the
case reported the plague virus first gained entrance through the
skin lesions of the legs into the inguinal glands, where only a
moderate multiplication occurred. The bacilli were then trans-
ported in the shape of a metastatic embolism into the lungs, from
where the embolish grew until it obliterated the pulmonary artery.
During the time these pathologic processes were going on, the
symptoms were so mild that the plague-infected patient never
stopped his regular work nor felt called upon to consult a physician.

GROUP IV. PRIMARY UNCOMPLICATED PLAGUE

PNEUMONIA.

Case No. 17. Primary Uncomplicated Plagiie Pneumonia.

[Necropsy Protocol No. 970. A. Q., Chinese, male, 30 years old, a shopkeeper
from No. 67 Tetuan, Santa Cruz. Sick six days ; died May 18, 1904, at 10.30
p. m. Post-mortem examination made thirteen hours after death.]

The body of a well-developed Chinese about 30 years of age.
Post-mortem rigidity moderately marked ; post-mortem lividity well
marked, extending to the anterior surfaces of the body. The skin
as a whole is markedly cyanotic. The right axillary glands are
slightly palpable; the other superficial ones are not. There are
no injuries, wounds, or abrasions of the integument. On section,
a moderate amount of dark, fluid blood escapes from the veins.
The muscles are fairly moist and of a dark red (smoked meat)
color. The serous membranes are injected and rather dull. The
pericardium is much injected and contains a slightly increased
amount of a yellowish somewhat turbid fluid. The heart is
normal in size, the left ventricle contracted, and the right one
dilated. At the sulcus a number of subepicardial hemorrhages are
seen, the largest of which is about 0.5 to 0.6 centimeter in diameter.
Both sides contain gelatinous post-mortem clots. The valves, the

109

endocardium, etc., are normal. The myocardium is of good con-
sistency and reddish-pink, with a slight shade of yellow. The
aorta and the coronaries are normal. Lungs: A few adhesions are
found at the upper lobe of the right lung. The left pleural cavity
contains an increased amount of fluid. The pleural surfaces are
deep purplish-blue, particularly on the right side, the left side
showing some admixture with grayish-wliite. On section, the
right lung is found to be much congested and highly oedematous.
The bronchi contain a fair amount of slightly blood-stained, frothy
mucus, the alveoli only a small amount of air. The left lung is
quite heavy, the lower lobe being entirely consolidated, and the
greater portion of the upper one is in the same state. On section
the consolidated pulmonary tissue is light brownish-gray. The
cut surface is quite granular, and the juice which can be scraped
off is bloody-grayish-yellow and quite turbid and opaque. In the
upper lobe the consolidated area gradually shades off into the
surrounding tissue and' is not sharply defined. On a closer inspec-
tion both of the consolidated areas, in the upper lobes as well as
in the lower show foci, var}dng in size from a pea to a hazelnut,
grayish-yellowish-red in appearance, and surrounded by much con-
gested, dark red areas. The bronchial glands are swollen, and
very soft and dark, their contents being changed into an almost
black, cheesy mass. The mucosa of the bronchi, the trachea, and
the lar}Tix are swollen and congested. The spleen is normal in
size and flabby, with a wrinkled surface somewhat bluish-gray in
color. On section the pulp is soft and protrudes over the surface,
being dark reddish-brown in color. The Malpighian bodies and
the trabeculas are not very distinct. The kidneys are normal in
size and their surfaces purplish-pink in color. On section, the
vessels are much engorged, the tubules grayish- white, and the
surface dull. The mucosa of the pelves is much injected. The
suprarenals are swollen, softened, and brownish- purple in color.
The liver is large and of increased consistency, its surface being
purplish-blue with a great deal of grayish- white in some places.
The cut surface is decidedly pinkish-yellow and as a whole dull.
The vessels are much engorged. Stomach: The serosa shows a
very few small hemorrhagic spots; the mucosa contains very
numerous petechiee and ecchymotic areas. The duodenal mucosa
likewise shows some hemorrhagic spots. The lymphatics of the
small intestine are somewhat swollen. The mediastinal, the mesen-

no

teric, the retroperitoneal, and the other superficial glands are all
moderately swollen and congested. On section their vessels are
found markedly engorged and their substance somewhat softened.
The most pronoimced enlargement is found in the axillary glands
of both sides. Smears from the consolidated areas of the left
lung show innumerable typical plague bacilli; those from the
glands and blood only a few.

Anatomical diagnosis. — Parench3Tnatous degeneration of the
kidneys; fatty and parenchymatous degeneration of the liver;
multiple subserous and submucous hemorrhages ; lobular pneumonia
of the right lung. Plague pneumonia.

Cultures inoculated from the consolidated areas of the right lung
developed a typical growth.

Microscopic examination. — Lungs: The alveolar spaces in the
consolidated area are all more or less completely occluded. The
distended air sacs, filled with a completely granular detritus,
alternate in an irregular manner with the alveoli which are filled
with a cellular exudate. The interalveolar septa are generally
markedly broadened, however, this is not due to a marked increase
in the cellular elements but to an oedema and hydropic swelling of
the fibers and cells forming the interalveolar septa. The capillaries
are greatly engorged and the walls of the veins are oedematous,
loose, and frequently in a state of hyaline degeneration. Fibrin in
finer or coarses threads is quite extensively seen, both in the interior
of the alveoli and in the interalveolar tissue. The cellular exudate
in the air spaces consist mostly of pol3Tiuclears with some mononu-
clears and desquamated epithelial cells. Erythrocytes are present
ever}'where, but in moderate numbers. Plague bacilli are found
throughout the consolidated area, but not in very dense zoogloeal
masses, though in great numbers in some places. In the renal tissue
the most profound changes are cloudy swelling and fatty degenera-
tion of the epithelia lining the uriniferous tubules. The inter-
stitial tissue is quite oedematous, and the interstitial capillaries are
filled ad mamimum. The glomerular vessels are likewise engorged,
but otherwise do not show any profound changes. Xo plague bacilli
are found in the renal tissue. The liver shows small, interlobular,
inflammatory foci, composed mostly of mononuclear and embr\'onal
connective tissue cells and a few polynuclears. However, these
foci are quite small. The parenchyma cells show fine as well as
coarse vacuolation. The interlobular capillaries contain a good

Ill

deal of blood. The spleen shows no marked histologic changes^
and only a veiy few bacilli are seen after a prolonged search.
Several lymph glands show marked dilatation and engorgement
of their blood vessels as well as some oedema; otherwise they are
fairly normal. The stomach exhibits greatly dilated vessels and
capillary hemorrhages between the glands and upon the surface of
the mucosa. No plague bacilli are found in the gastric areas of
blood extravasation. In fact, none of the organs except the lungs
contain any large number of these organisms. Outside the pulmon-
ary tissue they are practically not found at all. The necropsy
of this case shows it to be a pure plague pneumonia, without a
general septic or septico-pyemic dissemination of the bacilli.

Case No. 18. Primary Uncomplicated Plague Pneumonia.

[Necropsy Protocol No. 971. C. C, Chinese, male, 27 years old, from No. 67
Tetuan, Santa Cruz. Sick six days ; died May 18, 1904. Post-mortem exami-
nation fourteen hours after death.]

The body of a slender Chinese from 25 to 30 years of age. Post-
mortem rigidity well marked ; post-mortem lividity moderate. The
surface is slightly cyanotic. There are no external wounds or
ulcerations. JSTone of the superficial lymphatics are palpable. On
section the veins discharge a good deal of dark, fluid blood. The
muscles are fairly moist and reddish-brown. The serous membranes
are injected and dull. The pericardium is much congested, but
the pericardial fluid is normal. The heart is normal in size, the
left ventricle well contracted and the right one dilated. The
anterior surface of the left ventricle, the apex on all sides, and the
sulcus show numerous small subepicardial hemorrhages. Both sides
contain gelatinous coagula. The myocardium is rather soft, pale,
and reddish-pink. Otherwise the heart is normal. The aorta
and coronaries are normal. Lungs : The entire anterior and a part
of the posterior surface of the lower lobe of the left lung is com-
pletely adherent to the pleura costalis. After the removal of the
left lung it is found that the pleura pulmonalis of the lower lobe
is thickened, yellowish, and covered with a thin fibrinous deposit.
Both pleural sacs contain a slightly increased amount of fluid,
on the left side this is turbid and contains some fibrinous flocculi.
Externally the left lung is purplish-blue and the right one scarlet-
pink. On section it is found that the lower lobe of the left lung
contains a central area of pneumonic consolidation. In front this

112

extends as far as the pleura, and posteriorly and below it reaches
to within about one centimeter of the pleural surface; but above
there are still several centimeters of pulmonary tissue not yet in
a state of consolidation. In the consolidated area the tissue is
dark brownish-gray with lighter grayish-yellow spots. The cut
surface is granular. The juice which is scraped off is turbid,
grayish-white, creamy, and purulent. The area of consolidation
is sharply defined from the rest of the pulmonary tissue, which is
very much congested, dark brownish-red in color, and very oede-
matous, containing very little air. The upper lobe of the left side
is congested and oedematous and contains much dark, fluid blood.
The right side on section is found to be moderately congested and to
contain quite a fair amount of air. The bronchial mucosa and that
of the trachea and larynx are congested. The bronchial glands are
swollen, softened, and dark purplish. The spleen is small and flabby
and its surfaces wrinkled and bluish-gray. On section the dark-
brown pulp is found to be softened, the trabeculse visible, and the
Malpighian corpuscles swollen. Kidneys are greatly congested. On
section the vessels stand out very prominently on a very markedly
grayish-yellow background. The surface is very dull. Liver : The
surface is bluish-purplish-pink with gray mottling. The consist-
ency is moderately increased. The cut surface is yellowish-brovra
and dull. The vessels are much engorged and the lobules enlarged.
The gall bladder and ducts are normal. The gastric and duodenal
mucosa shows numerous petechise. The petechise are so numerous
and crowded in the mucosa of the stomach at the fundus that they
have become more or less confluent at their margins. None of the
superficial or deeper l3anph glands, excepting the bronchial ones,
show any marked changes.

Smears from the consolidated area of the lung show innumerable
typical plague bacilli ; others only a very few.

Anatomic diagnosis. — ParenchjTnatous degeneration of the kid-
neys and liver; multiple subserous and submucous hemorrhages;
pneumonia; acute adhesive fibrinous pleurisy. Plague.

Microscopic examination. — Sections from the consolidated area
of the lung show alveoli filled with mononuclear and poljTiuclear
leucocytes, erythrocytes, and alveolar epithelia. The polynuclear
leucocytes predominate considerably. Some of the air spaces show
a coarse network of fibrin, though such places are not numerous.
However, fibrin is found very extensively in the interalveolar capil-

113

laries and in some of the smaller pulmonary veins; it is present
both in the shape of a reticulnm and in that of tubidar or solid
thrombi. Here and there an extension of the intravascular fibrin
into the vessel wall and into the perivascular tissue is encoun-
tered. The interalveolar septa in this case, unlike those in the
preceding one, are not at all widened but rather delicate, excepting
the space occupied by the distended capillaries. Bacilli are found
extensively throughout the sections ; here and there in a dense clump
located in an alveolus and in other places distributed in such a
way that it may be said that the cells of the exudate are embedded
in a loose reticular matrix consisting of plague bacilli. In the
renal tissue the tubular epithelium shows cloudy swelling, granular
and fatty degeneration, and a loss of nuclei. Many of the tubules
are collapsed and the interlobular connective tissue is oedematous
The capillaries, includging those of the glomeruli, are congested,
and a few microscopic areas of blood extravasation are found near
the capsule. Sections of the liver show cloudy swelling and fatty
degeneration of the parenchyma cells and great congestion of the
capillaries and veins. However, there are no interstitial changes.
The lymph glands exhibit engorgement of the blood vessels and
lymph channels, some slight oedema, possibly some increase in
fibrous connective tissue, and the presence of quite a number of
plasma mast cells. Otherwise no changes have occurred. The
vessels of the gastric and duodenal mucosa are greatly engorged,
and some blood extravasation has taken place into the mucosa upon
its surface. N"o plague bacilli are found in these small hemorrhagic
areas ; in fact, practically none of these organisms are found outside
the pulmonary tissue. (The tissue from the spleen of this case
had been lost.)

GROUP V. PRIMARY PLAGUE PNEUMONIA WITH SECOND-
ARY PLAGUE SEPTICO-PYEMIA.

Case No. 19. Primary Plague Pneumonia with Secondary

Septico-Pyemia.

[Necropsy Protocol No. 962. F. S., Pilipina, female, 30 years old, from No. 148
Calle Anda, Intramuros, Manila. Died May 7, 1904, at 5.30 p. m. Cause of
death unknown. Plague suspected. Post-mortem examination made sixteen
hours after death.]

The body of a fat, stout woman, probably 40 years old. Post-
mortem rigidity moderate; lividity well marked. The posterior
surface and the sides of the trunk, as well as the extremities, show

25483 8

114

numerous small petechise and ecchymoses, varying in size from one
to several millimeters. The surface as a whole is cyanotic. On
section the superficial veins discharge a good deal of dark, fluid
blood. The serous membranes are highly injected and somewhat
dull. The pericardium contains the usual amount of fluid, which
is turbid and rather dark yellowish. The heart is somewhat
enlarged, soft, and flabby. The left ventricle is very moderately con-
tracted and the right one dilated, both of them containing clotted
blood. The auriculo-ventricular openings are somewhat increased
in size. The myocardium is soft and flabby, of a pinkish-yellow
color, and easily torn. Otherwise the heart is normal. The lungs
are adherent; the adhesions are easily broken up and are most
marked on both the lower lobes and at the right apex. Both pleural
cavities contain an increased amount of fluid of a turbid, slightly
blood-stained character. The surfaces of both lungs are highly
congested. The lower lobes particularly present numerous sub-
pleural, hemorrhagic areas of an almost black purplish-blue color.
Alternating with these are places where the surface is more grayish-
pink. The hemorrhagic areas protrude somewhat over the general
surface, so that the latter is somewhat uneven. On section the
pulmonary tissue is found to be much congested with dark, fluid
blood in some parts of the lower lobes this amounts almost to
complete red hepatization. Inside these very much congested areas
are seen spots of the size of a pea or smaller, which are grayish-
red or more decidedly grayish-white. The lower lobes contain very
little air, the upper ones a larger amount. The bronchial glands
are not much swollen, though greatly congested, softened, and pur-
plish-black in color, being somewhat hemorrhagic on section. The
mucosa of the bronchi, the trachea, and the larynx is swollen and
highly congested. The spleen is enlarged to about twice its normal
size; its surface is bluish-purple and its capsule smooth and not
very transparent. The cut surface is reddish-brown, uneven and
granular, and the pulp protrudes. The trabeculse are distinct;
the Malpighian bodies are not. The kidneys are soft and almost
gelatinous, their external surfaces being smooth, much congested,
and deep purplish-blue. The capsules are transparent and peel off
easily. On the cut surface the vessels appear highly engorged,
the glomeruli stand out as deeply injected points, the tubules are
grayish-white, and the surface as a whole is quite dull. The pyra-
mids are much injected. The mucosa of the pelves is congested.

115

The suprarenals are swollen, soft, and dark brownish-yellow in
color. The liver is large, of a somewhat increased consistency, and
elastic. Its capsule is shining and transparent. The general color
is pinkish-purple, but the areas of this hue alternate with places
of a grayish-yellowish-pinkish color. On section the organ is found
to be much congested. The hepatic veins discharge much dark,
fluid blood. The surface is of a deep yellowish-brown and is
quite dull. The acini are enlarged and the boundaries are not
very distinct. Here and there a grayish-white point is seen on
the cut surface. The gall bladder is distended, its walls cedematous,
and its mucosa swollen. The bile is viscid and dark greenish-yellow.
The ducts are open. The serosa stomach and the intestines is much
injected and rather dull. The mucosa of the stomach and the
duodenum shows numerous small, hemorrhagic areas. The pan-
creas is normal. The uterus is markedly enlarged and rather soft.
Its mucosa is softened, swollen, and hemorrhagic. The cavit}'',
however, contains no free blood. The serosa of the uterus as well
as of the appendages is much congested. The uterine muscularis
is of good, firm consistency. The left ovary is enlarged to the size
of a large walnut, nearly perfectly spherical, microcystic, and of
a deep black-bluish-purple color. The right one is small, firm, and
less congested. ISTo fresh corpus luteum is present. The inguinal
and cervical glands are slightly enlarged and moderately congested
but not softened. The internal h'mphatic glands, such as the
mesenteric, the retroperitoneal, the iliac, and the mediastinal, are
all very moderately enlarged and markedly congested, but neither
markedly softened nor hemorrhagic.

Smears prepared from the different organs show the following:
Lungs: Very many typical plague bacilli, also a number of very
small diplococci. Spleen: A moderate number of plague bacilli.
Liver : Quite a few bacilli. Heart's blood : Quite a few plague
bacilli and some small cocci. Kidneys : Numerous plague bacilli.

Anatomical diagnosis. — Lobular pneumonic foci; congestion and
beginning diffuse red hepatization of both lower lobes ; general con-
gestion of the lungs; subpleural hemorrhages; congestion and
parenchATiiatous degeneration of the liver and kidneys; submucous
hemorrhages in the gastric and intestinal mucosa; hemorrhagic
endometritis; microcystic degeneration and congestion of the left
ovary. Plague pneumonia and septicaemia.

116

Microscopic examination. — Lungs: Sections from the most con-
gested portions of the lower lobes show all the blood vessels, includ-
ing the interaveolar capillaries, to be engorged ad maximum.
Xumbers of air spaces are filled with a granular detritus including
desquamated cells, some white and a few red corpuscles. Mixed
with these elements are a moderate number of typical plague bacilli,
which in some of the alveoli are present to a considerable extent.
The majority of them are found in close proximity to the inner
lining of the alveolus and not free in the center of the air space.
Alveoli completely filled with innumerable plague bacilli are also
seen. In such masses of bacteria one occasionally encounters a
vessel broken into by these organisms ; this observation refers alike
to the capillaries, the veins, and the arteries. On the other hand,
a few interalveolar capillaries are found to be completely thrombosed
with densely packed plague bacilli. Alternating with alveoli, more
of less completely filled, are air spaces which are open and even
emphysematous, the interalveolar space having occasionally been
ruptured. Xo fibrin is found in any of the alveoli. Kidneys:
The most striking histologic change in the kidneys are metastatic
emboli in the glomerular capillaries, completely filling some of the
loops of the tufts. However, such emboli are foimd in a limited
number of glomeruli only; nor are any tufts seen where all the
capillaries are obliterated. The embolic closure is generally con-
fined to one lobe of a glomerulus. Sometimes the embolic bacterial
mass extends into the afferent or efferent vessel (it is impossible to
decide which of the two is affected). The neighborhood of such
thrombosed vessels shows small microscopic areas of blood extravasa-
tion, in which few bacilli are found. All the renal vessels are much
engorged, particularly the small vessels, and the interstitial tissue
is quite oedematous. Small microscopic areas of blood extravasa-
tion are encountered all over the sections. A few bacilli are often
seen in such areas as well as in the tubules, the lymph clefts, and
even occasionally in the small arteries and veins. The tubular
epithelium shows profound cloud swelling and fatty degeneration.
The interlobular capillaries of the liver exhibit the same metastatic
emboli, composed of dense masses of plague bacilli, such as have
been described above for the renal tissue. However, these bacterial
thrombi are not very numerous, and in general the liver capillaries
are free from bacteria. On the other hand, a small number of
bacilli were seen in one interlobular vein. The liver parenchyma

117

cells show marked fatty degeneration. In the spleen the j\Ialpigliian
bodies and the pulp spaces are not well marked, and the latter are
densely tilled. The proportion of leucocytes is increased. The
pulp spaces here and there show numbers of bacilli in fairly dense
groups; but they are not nearly as crowded in the spleen as in the
kidneys and liver. The gastric mucosa shows degenerative changes
in the glandular cells, in most of which the nucleus stains poorly
or not at all. Plague bacilli are found here and there in the loose
connective tissue of the mucosa. The interlobular capillaries are
enormously dilated, and blood is extravasated into the inter-
glandular tissue and upon the free surface of the mucosa. Few
plague bacilli are found in the oedematous and hemorrhagic inter-
glandular tissue and in the areas of blood extravasation upon the
mucosa. However, in general, the blood vessels do not contain any
plague bacilli. The uterine mucosa is quite oedematous and its
vessels much congested. Otherwise the uterus does not show any
marked changes.

A consideration of the morbid anatomy and of the histopathology
of this case shows that we are dealing with a primary plague pneu-
monia, in which the virus was very promptly carried by the blood
current from the lungs to the distant organs. It is probable that
the plague bacilli first entered the lungs by inhalation, multiplied in
the alveoli, and invaded some of the interalveolar capillaries, where
they formed solid thrombotic masses. Particles of the latter taken
up by the blood current reached the kidneys, liver, spleen, etc.,
where in several instances they grew into completely obliterating
emboli. It is a most remarkable fact that, in spite of the many
bacterial foci interpolated into the vascular system, the general
blood current did not become flooded with bacteria. In general the
lumina of the vessels, both large and small, are found free from
bacteria. Another point of great practical importance may be
learned from a histologic stiidy of this case, namely, that not
merely the sputum but vomited matter, feces, and urine may be
highly infectious.

GROUP VI. PRIMARY PLAGUE SEPTICAEMIA.

Case No 20. Primary Plague Septicemia.

[Necropsy Protocol No. 983. L. T. T., Chinese, male, 28 years of age, from
No. 211 Santo Crlsto Street, San Nicolas. Sick for ten days; died June 4,
1904, at 1 a. m. Post-mortem examination made fifteen hours after death.]

The body of a rather small, slender, young male Chinese, about
35 to 30 vears old. ISTutrition onlv fair, rather emaciated. The

118

skin is somewhat c5'^anotic. There are no ulcerations, wounds, or
recent scars. Eigor mortis is absent; the post-mortem lividity
is well marked. jSTone of the external lymphatics are palpable.
On section of the body a considerable amount of very dark, fluid
blood escapes. The serosa of the stomach and intestines is very
much congested and the small vessels stand out very prominently.
The serous membranes are rather dull. A few hemorrhagic spots
are seen in the peritoneal covering of the stomach and of the small
intestines. The serous covering of the bladder likewise shows a
few petechise. The abdominal fluid is somewhat increased, slightly
turbid, and rather dark yellowish. The pleural sacs contain a
normal amount of amber-yellow turbid fluid. Firm adhesions are
found in the region of the apex of the right lung. The .pericar-
dium shows many engorged vessels, but is otherwise normal; so
is the pericardial fluid in amount, color, etc. Heart: The left
ventricle is well contracted, while the right one is dilated. The
external surface shows several dozen irregularly distributed sub-
epicardial hemorrhages, varying in size from a small punctiform
dot to an area of 0.5 to 0.6 centimeter in diameter. The
myocardium is of fair consistency and light pink with a little
tinge of yellow. JSTo further dissection of the heart is made,
since it is to be photographed. The large vessels are normal. The
lungs are expanded and hea\'3' and the external surface is more
or less deep bluish-purple. This color is most intense over the
lower lobes, on which also a few ecch}Tnotic spots are seen. On
section the pulmonary tissue is brown in color and full of blood.
In the left lower lobe there is some admixture with grayish-yellow,
but there are no areas of distinct consolidation. A good deal of
blood and serous fluid can be pressed out of the pulmonary tissue.
The mucous membrane of the bronchi, the trachea, and the larynx
is swollen and highly injected. The base of the tongue is much
swollen and oedematous. The bronchial glands are quite dark,
but not materially, if at all, increased, in size, or markedly softened.
The spleen is enlarged to about twice its normal size; the capsule
is wrinkled and grayish-bluish-purple in color. On section the
organ is dark reddish-brown. The pulp is very soft and protrudes
over the surface, which is quite granular. The trabeculse and
Malpighian bodies are distinct. Kidneys : The capsules are smooth
and transparent and grayish-bluish-purple in color; they peel off
easily. The external surface shows a few small subcapsular hemor-

119

rhagic spots. On section the glomeruli and straight vessels are
much engorged, the uriniferous tubules grayish-yellow and the
surface dull. The mucosa of the pelves is injected, showing a
very few small punctif orm hemorrhages ; the ureters likewise exhibit
a few petechise. The mucosa of the bladder is thickened and
contains very numerous, densely crowded small petechias. The
suprarenals are swollen, soft, and yellowish-brown in color. The
liver is large, with rounded margins. Its capsule is smooth and
transparent and externally is bluish-purple, alternating with
yellowish-gray. On section the surface is dull and grayish-yellow
and the veins contain much blood. The consistency is markedly
increased; the acini enlarged. The gall bladder is distended with
a good deal of dark green viscid bile. The ducts are open; there
are no stones. The mucosa of the stomach and the small intestine
shows numerous small, irregular hemorrhagic areas. Both the
superficial and the deep lymph glands are very little, if at all,
enlarged, though they are markedly congested, particularly the
mesenteric and the inguinal ones.

Anatomical diagnosis. — Congestion and oedema of the lungs;
fatty degeneration of the liver; acute parenchymatous nephritis;
multiple subserous and submucous hemorrhages (lungs, heart,
kidneys, ureters, bladder, stomach, intestines). Plague septicaemia.

Smears from the different organs, including the glands, spleen,
liver, limgs, etc., show a moderate number of plague bacilli. Tubes
inoculated from the blood, the lungs, and the glands developed
tj'pical plague bacilli, but the cultures were contaminated by a
small diplococcus.

Microscopic examination. — The histologic changes in the kidneys
are very profound. There is universal cloudy swelling and fatty
degeneration of the tubular epithelium. The tubules are generally
filled with a granular detritus, and in many instances sharply out-
lined hyaline casts are found. These hyaline masses are composed
of a homogeneous material (staining with eosin and somewhat
with methylene blue) ; however, this does not give the tinctorial
fibrin reaction. While the degenerative changes of the renal
epithelium are. most pronounced in the convoluted tubules, they are
also present in the straight ones. The glomerular capillaries are
generally not much altered, but here and there a partial hyaline
(fibrin) thrombosis can be seen. Occasionally one observes an inter-
tubular thrombosed vessel. Plague bacilli are found in small

120

groups in some of the glomeruli; they are also observed both in the
capillaries and between them. A very few isolated organisms are
encountered in the interstitial connective tissue between the tubules.
The liver parenchyma cells show fine and coarse vacuolation. Inter-
lobular inflammatory foci composed of small mononuclear cells are
seen here and there, but the interlobular fibrous connective tissue is
not increased. The interlobular capillaries and the vessels in
general are much engorged with numerous, densely crowded red
blood corpuscles. In a number of places inside the capillaries
groups of plague bacilli are seen. However, this infection of the
hepatic blood system is not general, the bacilli being confined to
a number of more or less isolated spots. A good deal of granular
bile pigment is found scattered throughout the hepatic tissue.
The pulmonary sections show greatly engorged capillaries and
veins, with an increased number of leucocytes in some of the latter.
In a number of places the capillaries contain groups of plague
bacilli. The alveoli contain desquamated epithelia and here and
there a little extravasated blood. Otherwise there are no grave
changes. N'o plague bacilli are seen in the alveoli. Spleen: The
follicles are hazy in outline, the boundaries of the pulp spaces are
indistinct and the latter are densely crowded with red blood cor-
puscles. The cells forming the follicles contain many large mono-
nuclears with a large hyaline protoplasmic body. A considerable
number of nuclei in the large hyaline mononuclears show a general
pyknosis or lumping of the chromatin into dense granular masses.
Plague bacilli generally are disseminated in moderate numbers
throughout the splenic tissue, and in some parts of the pulp in
larger groups. A veiy few of the smallest vessels contain hyaline
fibrin thrombi. The inguinal lymph glands show much dilated
and engorged vessels and an increase in the connective tissue at
the hilum. Plague bacilli are seen here and there in little isolated
groups. In the gastric mucosa the hemorrhagic spots are situated
directly below the surface. The extravasation has taken place
from the interglandular capillaries. These hemorrhagic areas are
found to contain fairly numerous plague bacilli. It is perhaps
possible that the portal of entrance of the plague bacillus in this
case was the hnigs. However, since no areas of consolidation were
found and the infection of the lungs was quite moderate, the case
has been classified as one of primary plague septicaemia.

121

ANALYSIS OF THE TWENTY CASES REPORTED AND SUM-
MARY OF PATHOLOGICAL FINDINGS.

An analysis of the twenty cases of plague reported above shows
that the total figure is made up of:

Cases.

Group I. Primary uncomplicated bubonic plague 11

II. Primary bubonic plague with secondary plague septico-
pyemia 4

III. Primary bubonic plague with secondary plague pneumonia.. 1

IV. Primary uncomplicated plague pneumonia 2

V. Primary pneumonia with secondary septieo-pyemia 1

VI. Primary plague septicaemia 1

Sixteen of these twenty cases were of the bubonic type, three of
the pneumonic, and one of the septic type. Of the bubonic cases
there were:

Cases.

Inguinal buboes 11

Axillary buboes I

Cervical buboes 4

The great preponderance of the bubonic type of plague cases is
fully in accord with the observations made by the Indian Plague
Commission on a very large amount of material; and the pre-
ponderance of inguinal buboes over cervical and axillary ones
is likewise the rule among races and in localities where the people
in general are barefooted. Of the cases of cervical buboes there
were three found in children, among whom their occurrence is the
most common, and one in a man of 63. Twelve of the 20 cases
occurred in native Filipinos and 8 in Chinese, 15 in males, and 5
in females. The great preponderance of males over females is
partly due to the fact that in one part of the affected population —
namely, the Chinese — the greater proportion consists of males.
However, even in India the number of cases in males greatly
exceeds that in females, though not in the proportion of three
to one. As to age, the cases reported range from 5 to 63 years, which
is in accord with the general experience gained on a large scale.
The majority of our twenty cases — viz, thirteen — occurred between
the ages of 20' and 40. Almost all of tbe plague victims came
from the lowest walks of life of the native and Chinese population.
One of the cases was that of a Chinese shopkeeper or merchant.

122

PORTAL OF ENTRANCE OF THE VIRUS.

As is well known, the portal of entrance of the plague virus can
not always be found. In the sixteen bubonic cases there were
seven in which even the slightest indication of the probable portal
of entrance was absent (cases Nos. 1, 5, 6, 7, 8, 12, and 14). In
the majority of the remaining nine cases of bubonic plague proper
the portal of entrance was more or less unmistakably indicated. But
in connection with this subject one must not forget that a secondary
skin plague lesion might be mistaken for the primary portal of
entrance. This is of course particularly liable to happen in cases
in which but little, if anything, is known of the clinical history.
Where a reliable clinical history can be obtained such a mistake
is less liable to occur. In the three pneumonic cases, the portal
of entrance of the virus was the lungs, because the changes in the
bronchial glands were such as to destroy the probability of their
being the first focus of infection. In case No. 20 — primary plague
septicaemia — there was no evidence of an intestinal origin ; however,
one might in this case suppose that the bacilli were inhaled, without
causing a distinct pneumonia, entering the blood current almost
immediately and in this manner producing a general septicaemia
without any manifest focal localization.

PERIOD OF INCUBATION.

The period of incubation of plague, as a rule, is a short one. The
Indian Plague Commission has compiled a table of cases in which
the time of infection could be fixed beyond doubt, it being contracted
during post-mortem examinations or during some similar manipula-
tion of fatal human plague cases. From their table it appears that
the period of incubation generally ranges from one to five days.

"While thus," the report of the Commission (Vol. V, p. 88) says,
"no facts have been reported to us which establish that the incubation
period may be prolonged beyond the period of five days, the limit fixed
by the numerous cases detailed above, * * * we think that it is
a matter of importance to point out, that where the plague first takes the
form of pestis minor, and where afterwards pestis minor develops, owing
to some subsequent loss of resisting power, into typical bubonic plague,
there is a possibility of a considerable interval elapsing between the time
at which the infection was contracted and the time at which the clinical
symptoms became typical. Such cases. Important as they are in the
epidemiological study of the disease, as indicating one of the possible

123

but quite exceptional ways in which plague may be carried about to
distant centers over sea, are, it must be observed, of extremely rare
occurrence. One such case has, however, come unoificially to our knowl-
edge in Poona."

THE LYMPH GLANDS IN BUBONIC PLAGUE.

In the majority of cases the portal of entrance of the plague
bacillus is through the skin or the mucous membranes. We have
already emphasized the fact that there is no case of human plague
on record in which the entrance of the bacillus through the intes-
tinal mucosa could be demonstrated beyond doubt. After the plague
bacillus has gained access to the body, it generally travels through
the lymph channels to the nearest gland or glands, where it then
multiplies. Indeed, the multiplication of this organism in the
lymph glands in most cases of bubonic plague is undoubtedly in
excess of any other bacterial proliferation in any other infection,
not excluding lepra. In the lymph glands the changes produced
may vary from comparatively minor ones to those of the most
profound degree. From a study of the lymph glands in the various
stages of the infection it appears that the first change produced
is vascular dilatation and engorgement and oedematous infiltration
with a perivascular proliferation of the connective tissue elements.
Even in cases of mild infection, one generally finds an increase
of connective tissue at the hilum and usually marked vascular
dilatation and oedema of the gland. The effect of the toxines and
the other metabolic products of the proliferating bacilli clearly
brings about an early damage to the vessel walls. However, this
damage may not find a pronounced morphologic expression. From
statements made in literature it appears that a well-marked hyaline
degeneration of the vessel walls is always found. We can not
confirm this observation, because we have frequently found an
infected gland with vessels, the walls of which, to all intents and
purposes, appeared to be morphologically intact. However, there
always is noticeable a great dilatation and engorgement of the ves-
sels, factors which, as we well know from general pathology, are
perfectly sufficient so to damage the vessel walls as to render them
pervious to the serum and to the corpuscular elements of the cir-
culating blood. Hence, it is not necessary, in order to explain
some of the tissue changes in plague, always to look for a degenera-
tion of the vessel walls with grave morphologic changes. After a

124

condition of dilatation and engorgement of the vessels with general
cedema of the gland tissues has been established, diapedesis of -the
red blood corpuscles occurs; so that, as a rule, a lymph gland
infected to any extent with plague bacilli shows blood extravasation.
When the infection has become very extensive and the number of
bacilli very great, we generally encounter the most profoimd tissue
changes in the glands, associated with extensive blood extravasation.
To the naked eye a gland in this condition appears much swollen,
more or less softened, and from dark scarlet to brownish-red, with
yellow or yellowish-red mottling. Since the blood extravasation
extends beyond the gland proper, the periglandular tissue is like-
wise of a hemorrhagic color. The tissues in the neighborhood
of the gland are oedematous to a considerable extent. If the finer
histologic changes of the gland are studied, it is found that the
original tissue has frequently become necrotic; the differentiation
into cortical and medullary portions and into follicles and cords
is lost. The capsule of the gland has become loosened by oedema-
tous and cellular infiltration, and the latter extends far into the
periglandular tissue. Most of the original cells of the gland show
evidences of nuclear disturbances (pyknosis, etc.) and of coagula-
tion necrosis, and a large number of red blood corpuscles infiltrate
the entire tissue and invade the periglandular areas. The vessels
are greatly dilated and engorged and their walls are frequently
loosened by hydropic swelling and cellular infiltration ; or they may
be in a condition of more or less complete hyaline degeneration. Not
infrequetly one finds proliferated lymphatic endothelia in larger
numbers in the infected glands; these endothelia may or may not
show phagocytic properties, other cells or plague bacilli frequently
being included in them. Plague bacilli are often present in the
glands in dense zoogloeal masses. From such a center of enormous
infection the bacilli infiltrate the rest of the gland and the peri-
glandular connective tissue in more or less continuous groups.
In several of our cases we have seen in extensively infected and
hemorrhagic glands, a perfectly homogeneous vacuolated hyaline
material, which has a strong affinity for eosin and which we con-
sider a derivative of degenerating, agglutinated red blood corpuscles.
In fact, sometimes the derivation of the hyaline material from this
source becomes so obvious that there can be no doul)t of its origin.

125

FIBRIN FORMATION IN THE GLANDS AND IN THE

OTHER ORGANS.

The homogeneous material just described is not true fibrin, and
does not give the tinctorial fibrin reaction of Weigert. However,
in plague true fibrin is found in the primary bubo in quite a number
of cases as well as in the organs distant from the focus of infection.
We encounter perfectl}' solid hyaline fibrin thrombi, or some vessels
may be partly occluded by a hollow tubular wall thrombus or by
a more or less open reticulum of fibrin. Such reticula, particularly
in the bubonic glands and in the spleen, are also found in an extra-
vascular location. Occasionally one sees threads connecting the
intravascular and extravascidar fibrin reticula. Sometimes fibrin is
found, not in the shape of threads, but as granular, more or less
solid material, always of course giving a typical Weigert's reaction.
In the glandular buboes we observed fibrin in the shape of hyaline,
vascular thrombi, or in the form of extravascular fibrin reticula,
with or without a connection of the intravascular and extravascular
deposits (in seven cases, Nos. 2, 9, 10, 11, 12, 15, and 20). Further
fibrin formation was observed in the spleen in five cases (jSTos. 5,
10, 11, 12, and 20), and in the lungs in three (Nos. 17, 18 and 19).
Fibrin may be found in several organs in the same case (No. 10,
in the primary bubo, the spleen, and the kidneys) ; or it may be
found in the primary bubo and nowhere else (Xos. 1, 3, 7, and 17) ;
or it may be encountered in the organs distant from the primary
bubo without being present in the latter (Nos. 11, 12, and 15).
In cases Kos. 18, 19, and 20, types of primary pneumonia and
primary septicsemia, there were of course no lymphatic buboes
present and no fibrin was observed in any of the lymph glands.
Fibrin thrombi in the kidneys were found in seven cases. (See
below "Hyaline Fibrin Thrombi of the Glomerular Capillaries.")

HEMORRHAGES INTO THE BUBO AND INTO THE
DISTANT ORGANS.

In studing the histopatholog}' of the infected hinph glands we
encounter other changes besides fibrin formation. These changes
are quite characteristic for plague and are found not only in the
glands but in locations distant from the focus of infection.

The feature which is most characterictic of plague infection is
its tendency to produce a general dilatation and engorgement of

126

the vessels and subserous, submucous, parenchymatous, and inter-
stitial hemorrhages. The most common locations of the latter are
the epicardium, the pleura, the peritoneal covering of the stomach
and intestines, and the mucosa of the stomach and intestines. There
may also be subcapsular renal hemorrhages and blood extravasation
into the pelves of the kidneys, the ureters, the bladder, and the male
and female genital organs.

In bubonic plague proper hemorrhages into the buboes are very
rarely absent. In only two of our sixteen cases of bubonic plague
proper were they not present; in these death was clearly due not
solely to the pest infection, but to a complication of circumstances
(Case No. 8, Banti's disease; Case No. 16, ambulatory plague, ter-
minating by embolism of the pulmonary artery). In fourteen out
of sixteen cases the primary bubo showed a hemorrhagic condition.
The heart in most of our cases showed subserous hemorrhages.
In this organ they were found seventeen times, varying in size
from a few small petechise to numerous and not infrequently large
ecchymotic spots. The other internal organs, arranged in the order
in which hemorrhages occurred in them most frequently are as
follows: Stomach, fourteen times; intestines, eight; kidneys, six;
bladder, three ; and liver and ureters, each twice.. Other organs in
which hemorrhages were occasionally found are the gall bladder,
the epiglottis, the esophagus, and the th}T2ius. The most extensive
and most widespread hemorrhages were found in Case No. 12 —
namely, one of bubonic plague in a male Filipino with secondary
septico-pyemia and metastatic dissemination of the bacilli. The
primary inguinal bubo itself showed most extensive hemorrhages
and an uninterrupted continuation of them from Scarpas' triangle
up to the right kidney, involving in the area of blood extravasation
all the glands, the periglandular tissue, the sheaths of the large
vessels, and the perirenal, loose arolar tissue. The heart, the kid-
neys, the ureters, the bladder, the liver, the stomach, the oesophagus,
and the small and large intestines, all showed either subserous or
submucous hemorrhages, or a combination of both ; blood extravasa-
tion was also seen in the anterior mediastinum. On the other hand.
Case No. 8, one of the primary inguinal imcomplicated bubonic type,
did not show a single hemorrhage. This is the case in which we
found a spleen weighing 865 grams and a cirrhotic liver. It is
reasonable to suppose that this patient had no resistance to the

127

plague infection and succumbed speedily before the characteristic
tendency to free hemorrhage could bcorae manifest.

The Austrian commission, in particular, held that multiple
hemorrhages in plague are dependent upon the direct presence of
bacilli. However, this view is not adopted by most observers;
agreeing with the majority of authors we are strongly opposed to
it. In all of our cases we examined the hemorrhagic areas care-
fully and in the larger number of them found the petachise and
ecchymoses free from them. Plague organisms were found only
exceptionally in the hemorrhagic areas, and only in such cases as
showed a septico-pyemic dissemination of the bacilli. To repeat,
in the greater number of cases of the uncomplicated types of bubonic
plague, we were unable to detect any bacilli in the numerous
subserous and submucous hemorrhages.

The German commission was never able to find any bacilli in
the juice obtained from the petechise; and several authors have
reported the typical occurrence of hemorrhages in guinea pigs
killed by dead cultures of plague bacilli. We have likewise suc-
ceeded in producing extensive blood extravasations in distant
organs in guinea pigs killed by intraperitoneal injections of dead
cultures. Hence, we must hold that the hemorrhages are entirely
independent of the local invasion of living plague bacilli and are
due to the toxines which have entered the general blood current.

PLAGUE AS A RULE NOT A GENERAL MICROBIC

INFECTION.

In uncomplicated cases of bubonic plague, even when the infec-
tion of the glands is extensive, bacilli are generally not found in
the vessels. In fact, one may observe an area composed almost
exclusively of zoogloeal masses of bacilli, in which there is still
found a vessel with a comparatively intact wall and with a lumen
entirely free from plague bacilli. In the introduction we have
already called attention to the fact that the results of our investiga-
tion do not justify us in classifying plague, in the strict sense of
the word, as a general hemorrhagic septicemia, but as a local infec-
tion with general symptoms and a general hemorrhagic toxemia.

From a histologic study of our material, we have come to the
conclusion that a general dissemination of the bacilli from the
glands is the exception and not the rule. Usually the infection

128

remains localized in a gland or in a group of glands. However,
there does occur a final agonal dissemination of the organisms,
which does not differ in character from that of other micro-
organisms in other diseases. In a number of cases an extension of
the invasion by bacterial metastatic emboli does take place, but even
in these instances there is no evidence that the plague bacilli
multiply throughout the entire blood system, although we encounter
either more or less numerous metastatic emboli, generally in the
liver and the kidneys.

THE INFECTION OF THE SPLEEN.

However, one organ is perhaps infected in every case of plague —
the spleen. The pest bacillus, even in uncomplicated bubonic cases,
always gains access to its pulp spaces, and here it evidently finds
conditions favorable to its multiplication.

In this respect plague may be likened to typhoid fever, in which
we also have a primary infection of the lymphatic tissue (Peyer's
patches) with an infection of the spleen which is never absent.
Another parallelism between typhoid fever and plague may be
found in a secondary infection of the lungs. Just as we find
secondary typhoid pneumonia dependent upon the presence of
enormous numbers of typhoid bacilli in the lungs, so we find
secondary plague pneumonia dependent upon the presence of
enormous numbers of plague bacilli in these organs.

That cases of plague are usually not complicated by a general
septicgemic dissemination of the bacilli is also strongly indicated by
the result of blood examinations on living human beings. (For an
abstract of literature on this subject see Herzog and Hare: Does
Latent Plague Exist, etc.?)

EXTENSION OF THE PRIMARY BUBO.

After a gland has once become infected by plague organisms and
been invaded by enormous numbers of bacilli, it is usual for the
other lymphatics of the same chain to suffer likewise; the latter
then present the same gross and finer pathologic changes as the
former. For instances, it may happen that the first gland to be
invaded is a femoral one, from which the infection spreads from
gland to gland until it reaches the retroperitoneal lymphatics high
up in the abdomen. As in some of our cases, we may then find a

continuous chain of glands, swollen, .softened, and hemorrhagic,
extending from below Pupart's ligament to the kidneys and
embedded in a completel}^ hemorrhagic and gelatinous connective
tissue. The same may be true of the axillary glands where the
typical changes and the hemorrhages may extend from the axillary
space into the thoracic cavity, and in the case of the cervical glands,
from the most superficial cervical to the deepest submental lymph
nodes and even in to the mediastinal glands.

THE OTHER LYMPH GLANDS IN PLAGUE.

Aside from the primary bubo with its hemorrhagic glands of the
first, second, third order, and so on, the glands in general may pre-
sent a greatly varied appearance, and we find all gradations from
the most profound to very insignificant changes. Tn septico-pyemic
cases metastatic emboli may be carried from the primary bubo
into a distant gland, and there establish a secondary bubo, which
does not differ materially either macroscopically or microscopically
from the former. But even in uncomplicated cases, without septico-
pyemia, the distant glands may l)e much swollen, greatly softened,
and highly congested, or they may practically show no changes at
all. Only a few glands may be affected, or many of them may
exhibit marked pathologic changes. In general, the rule holds good
that the more marked the tendency to widespread, subserous and
submucous hemorrhages, the more pronounced the swelling, etc.,
of the lymph glands, both superficial and deep. In plague pneu-
monia the bronchial glands may have the appearance of a primary
bu])o, or they may merely show some swelling, softening, and con-
gestion, without any blood extravasation. The lymph vessels
proper, aside from those situated in the infected glands themselves,
are as a rule not much changed, excepting those which connect the
different glands of the chain forming the primary bubo.

THE HEART AND THE CIRCULATORY SYSTEM.

As a rule the heart does not show any very pronounced changes
in plague, aside from those which are found as common features
in the various organs in this disease. The great frequency of
subepicardial hemorrhages has already been pointed out. The
coronar}^ vessels are generally greatly dilated and engorged, and the
smaller ones of both the visceral and the parietal layers of the
25483 9

130

pericardium are often distinctly visible as red tortuous streaks and
lines. The pericardial fluid is normal or somewhat turbid and
occasionally more or less increased in amount. The left ventricle
is contracted and the right one sometimes considerably dilated.
We have never seen endocardial hemorrhages or endocarditic proc-
esses. However, Duerck has described a case of plague pneumonia
with endocarditis verrucosa of the mitral valve, further com-
plicated by a purulent leptomeningitis of the convexity. This
case was evidently one of septico-pyemic plague endocarditis. The
myocardium is frequently of good consistency and of normal color ;
although sometimes it is rather soft, flabby, friable, pinkish-yellow,
and easily torn. Both sides generally contain chicken-fat clots
and much dark, fluid blood. The great vessels present no changes
peculiar to plague; but in Case No. 16, an ambulatory one, we
found an embolism of the pulmonary artery. In general the veins
and capillaries are dilated and engorged to such an extent that
some of the internal organs, more particularly the lungs and the
kidneys, are not only greatly congested but highly oedematous. If
one considers the great dilatation and engorgement of the vascular
system and the oedematous infiltration of the tissues met with in
plague, one is inclined to think of a hydremia of the blood. Such
a condition might easily be brought about in consequence of the
vasomotor and secretory disturbances which exist in plague, namely,
scanty or suppressed urine and dry skin on the one hand, with great
thirst and a larger ingestion of fluid on the other. Whether a
hydrsemia of the blood really exists in plague is a point, which,
as far as we know, has never been determined. This question could,
of course, not be decided by a count of the corpuscles, but only by
exact chemical methods for determining water and dry residue.
The dilatation and engorgment of the vascular system often
shows the smallest veins in the serous and mucous membranes as
distinct, more or less tortuous lines, while the overfilling of the
capillaries in the membranes named produces a uniform deep
hypersemia. In areas of this kind petechia and ecchymoses are
encountered. Microscopically the myocardium often does not show
any marked changes. In other cases a moderate degree of fatty
degeneration, pigmentary degeneration of the perinuclear zone,
fragmentation or segmentation are met with. However, in general,
the histologic changes of the myocardium are insignificant. We

131

have never been able to find any bacilli in the subepicardial hemor-
rhagic areas.^

THE LUNGS.

The lungs, in uncomplicated eases of bubonic plague as well
as in complicated ones, in fact in all cases of pest which we have
examined, show great congestion and oedema, with a corresponding
diminution of the amount of air contained in them. The external
surface is generally of a deep purplish color; the cut surface dis-
charges a large quantity of blood and serous fluid. The mucosa of
the bronchi, the trachea, and the larynx is more or less swollen, con-
gested, and reddened. Hemorrhages are found on the pleural
surfaces and sometimes on the mucosa of the bronchial tract,
including the larjTix; in one of our cases they were found in the
epiglottis. In cases of primary or secondary plague pneumonia
we find interlobular foci in the lungs, varying in size from that
of a mere point to that of a hazelnut. They are generally well
consolidated and in color grayish-reddish-white to brownish-red.
They are, as a rule, surrounded by a ring of intensely congested,
deep reddish-brown pulmonary tissue. The areas of lobular con-
solidation may become confluent so as to produce a picture of
complete lobar consolidation. We have not observed such cases,
but others have established their occurrence.^ In one of ours the
pneumonic area reached to the pleural surface, where it had pro-
duced a localized exudative, fibrinous pleuritis. In general it is
found that if the areas of lobular consolidation are situated near the
surface, the pleura in this region is somewhat prominent and
imeven, and is quite well differentiated from the surrounding sur-
face. In plague pneumonia the bronchial glands may or may not
assume the character of primary buboes. They may be enlarged,,
greatly softened, and hemorrhagic, or they may show but very

* No mention of the myocardium is generally made in the microscopic
reports of the twenty individual cases reported above. However, the heart
and other organs not specifically mentioned, such as the suprarenal glands,
the pancreas, male and female genital organs, etc., were examined micro-
scopically in most of the cases. Since no changes of a marked character
or of particular interest were found, these findings have not been given
in detail but are only referred to in the summary.

* In case No. 18, the same which showed the localized fibrinous pleurisy,
most of the left lower lobe was consolidated. So this case came very
near being a lobar pneumonia.

132

little change. On microscopic examination we find that the alveoli
are eitlier filled with larger or smaller numbers of bacilli or with
a cellular exudate consisting of leucocytes, alveolar epithelia, and
erythrocytes, mixed with smaller or larger numbers of plague
bacilli. The interalveolar septa are generally widened by an (ede-
matous infiltration and by a swelling of the cells and fibers. The
capillaries are greatly dilated and engorged; they may be free
from plague bacilli or may contain metastatic emboli in complicated
cases. Fibrin may be either present or absent.

THE SPLEEN.

Much emphasis has been laid upon the enlargement of the spleen
in plague. Some observers have even gone so far as to state that
this organ is always markedly enlarged in this disease and not
infrequentl}^ very much increased in bulk. However, we have,
among our i^ost-mortem material four cases (Nos. 4, 5, 10, and 17)
in which the spleen was not enlarged and two (^o. 14, Filipinos
sixty-three years old, and Ifo. 18, Chinese twenty-seven years old)
in which it was very small. On the other hand, most cases of
plague show a considerable increase in the size of this organ, which
then is generally about two to three times the bulk and weight of
the normal one (Cases A^os. 1, 2, 7, 9, 12, 13, 15, 16, 19, and 20).
In three cases (Nos. 3, 6, and 8) a very considerable enlargement
was found, in one of which at least an increase of the organ to 20 by
12 by 7 centimeters and a weight of 865 grams, was clearly due to
causes existing prior to the plagxie infection. One must not forget
that splenomegaly is a very common finding in the Tropics; and
hence if a very large spleen is encountered in a plague case the
possibility of this being due to some other cause must always be kept
in mind. We have taken great pains to search for the Donovan-
Leishman bodies in those of our plague and in other post-mortem
cases which showed extensive enlargement of the spleen, but we
have never encountered them. This demonstrates, to a certain
extent at least, that all cases of tropical splenomegaly can not be
attributed to the Donovan-Leishman infection. In plague the
enlarged spleen is generally, though not always, soft in consistency,
dark purplish-blue externall}^, and dark brownish-red on the cut
surface. On section the pulp generally protrudes and a large
quantity of juice can iisually be scraped off. The trabeculse as a
rule are distinct, but the follicles are commonlv not very clear.

133

Why the latter are not readily tlistinguishable is easily explained
by the microscopic examination of the organ, which frequently shows
small follicles indistinct in outline, owing to the fact that the cells
forming them are lost in the surrounding pulp spaces. The latter
themselves are generally not distinct and are occluded by cellular
elements, consisting of red blood corpuscles and nucleated leuco-
cytes. In a considerable number of our cases the spleen gave
evidence of an extensive proliferation of the endothelial cells of
the pulp spaces. Sometimes great numbers of these are seen, many
of them containing two or more nuclei. A number of them are
phagocytic and include either other cells or plague bacilli. As
already stated, in all of our cases the spleen showed an invasion
with bacilli, so that we are much inclined to look upon this as a
regular occurrence in plague.

THE GENITO-URINARY SYSTEM.

It had already been emphasized by Aarchow that in plague the
genito-urinary system often presents subserous and submucous hem-
orrhages. This is the common observation of all who have studied
the pathology of the disease, and it is also confirmed by our work.
As a whole the kidneys invariably show marked congestion, and
even to the naked eye evidences of parenchymatous degeneration
are never absent. On the cut surface there are seen uriniferous
tubules which are greyish-white or grayish-yellow as well as dull,
and engorged vessels, among which are the glomerular capillaries.
The Malpighian tufts are usually observed as intensely red points,
although at times they may appear as more or less solid, grayish-
red masses. This latter «,ppearance may easily be overlooked
until our attention has been drawn to it by a microscopic examina-
tion, M'hich fully explains why one might expect to see such solid,
grayish-red, swollen glomeruli.

A microscopic change which has been described by all who have
studied the kidney in plague is profound cloudy swelling of the
epithelium of the uriniferous tubules, with the presence of granular
or hyaline material in the latter.

HYALINE FIBRIN THROMBI OF THE GLOMERULAR

CAPILLARIES.

However, a very characteristic change in the kidneys which we
have found in seven of our twenty cases, has not, it appears, before
been described, namely, a hyaline fibrin thrombosis of the glomeru-

134

lar capillaries. These capillaries may be entirely or partly occluded
by genuine fibrin thrombi, which give Weigert's staining reaction.
The thrombi are either solid or hollow tubular wall thrombi.
Where they are found, it can generally be shown that they extend
into the afferent and efferent vessels and beyond these into the inter-
tubular ones. A careful study of the vessels fails to show any appie-
ciable morphologic change of their walls. The vascular endothelium
generally appears intact; occasionally some of the lining endo-
thelium may be missing, but this is certainly not general, but rather
exceptional. The fibrin thrombi are evidently formed independently
of the presence of plague bacilli in the kidneys; because in most
of the cases where we did encounter them in our material a very
careful search for these organisms in sections failed to reveal them.
However, in one case in particular there was a simultaneous occur-
rence of hyaline thrombi and bacillary emboli. In some places
the bacilli were actually located between the vessel wall and the
thrombus. However, since this was seen only in one case, it is
very clear that it was merely a coincidence; a causal nexus between
the bacilli and the thrombi did not exist. The very characteristic
hyaline fibrin thrombosis of the glomerular capillaries does not
appear to be found frequently in acute infectious diseases in which
the kidneys are greatly involved, nor, in fact, in any fomi of acute
or chronic nephritis.

Welch, however, appears to consider it as not at all an uncommon
occurrence, and makes the following statement in regard to it : "Capillary
hyaline thromboses are common in the lungs in pneumonia, and in
hemorrhagic infarcts. In general infective and toxic states they may be
present in the liver, the lungs, and above all, in the kidneys. ^ The most
striking example of this form of thrombosis with which I am acquainted
is encountered in renal capillaries, chiefly of the glomeruli of swine
•dead of hog cholera; or of animals infected with the hog cholera bacillus.
In extreme cases there is complete anuria, and it may be impossible to
force more than a minimal amount of injecting fluid into the renal
vessels. Section stained with Weigert's fibrin sta^n look as if the capil-
laries had been injected with Berlin blue. Ribbert found similar hyaline
thrombi in the kidneys of rabbits inoculated with 8. Pyogenes aureus.
I have repeatedly found them in various experimental infections and
in human infections. They occur in eclampsia. Bacteria are not neces-
sarily present, so that toxines are probably the underlying causative factor,
and for this there is experimental evidence."

It must be borne in mind that the term "hyaline thrombosis of the

^ Italics our own ; not in the original.

135

glomerular capillaries" is freqiiently very loosely used by authors who
have written on changes of the kidneys in infections and it generally
refers to an ordinarj' hyaline degeneration and not to a true hyaline
thrombosis. In fact, a very careful study of the literature impresses one
with the conviction that the latter is very rare. It has been mentioned
with some emphasis in connection with only one renal affection, namely,
late post-scarlatinal nephritis. Our attention was first called by Klebs
to the changes in the glomeruli in diseases of the kidneys who introduced
the term glomerulo-nephritis and who stimulated further research into
this histo-pathologic change. He states that after scarlatina, the kidneys
are found either slightly or not at all enlarged and very rich in blood,
and the glomeruli appear as small, whitish points, which in sections are
seen to contain little blood and are darker and more cloudy than the
uriniferous tubules. However, neither Klebs nor Langhans, who studied
kidneys with glomerular lesions in twelve cases of scarlatina, say anything
about hyaline fibrin thrombi in the glomerular capillaries. The latter
states expressly that the fibrin cylinders in the tubules are composed of
a hyaline material which is not identical with fibrin. Boehm, Goemans,
Fichera, and Scafiddi ' have recently published contributions to the patho-
logic histology of the glomerulus, but they have not seen any fibrin
thrombosis of the glomerular vessels. The last two authors describe
hyaline degenerations of the glomerular capillaries and state that in the
kidneys, with changes in the glomeruli in the kidneys, there frequently
occur affections of the capillaries. The process begins in some loops,
which become glass like and transparent and take certain stains homo-
geneously. The process then spreads to several which become fused and
so form a homogeneous mass poor in nuclei. The few nuclei left show
profound disturbances, such as karyolisis or karyorrhexis. In still more
advanced cases one sees, in place of the glomerulus, a body smaller than
the smallest glomerulus, which is globular and bounded by a capsular
membrane. The body itself consists of a homogeneous, transparent,
uniformly stained, hyaline mass, which shows no capillaries at all or
only traces of them, and in which no more capsular space can be recognized.
Nuclei, if present at all, are either small or poorly stained, shrunken,
pyknotic, or fragmented. The cause of the necrosis and hyaline degenera-
tion of the glomerular capillares may probably be attributed in this
case, as in others to profound disturbances of nutrition of the vessel
walls and to obliteration of the capillaries which prevents the blood
circulation. Fichera and Scafiddi expressly mention that the process
described is different from true capillary thrombosis as it has been observed
in post-scarlatinal nephritis. Pearce investigated the histopathology of
the kidney in twenty-three cases of scarlatina, but did not find glomerular
thrombosis in any of them. Hansemann microscopically examined the
kidneys in 120 cases with special reference to the changes found in the

. ^ Fichera and Scafiddi's quite exhaustive study contains a complete list
of the literature and quotes 110 articles on the normal and pathologic
histology of the glomerulus.

136

Malpighian bodies. His material included the following diseases : Nephri-
tis, after cold, parturition, scarlatina, diptheria, measles, croup, pneumonia,
typhoid, erysipelas, puerperal fever, endocarditis ulcerosa, malaria maligna,
constitutional syphilis, tuberculosis, eclampsia, atrophia infantum,
encephalitis neonatorum, cholera nostras, epidemic meningitis, empyema
without tuberculosis, carcinoma, pernicious anemia, leukemia, sunstroke,
and chlorate of potash-phosphorus-lead and arsenic poisoning. In none
of these affections did he ever find a hyaline fibrin thrombosis of the
glomerular vessels; in fact, he does not mention it, though he speaks
of amyloid degeneration. Posner is probably the first writer specifically
to mention the presence of typical fibrin in the kidneys, however, not
in the glomeruli but in the interior of the tube casts, found in the kidneys
of rabbits after the ligation of the renal artery. Israel observed retieula
of fibrin in the convoluted tubules, and solid fibrin masses in the cap-
sular space of the glomeruli in experimental anemic necrosis induced
bv ligation of the renal arterv. He evidentlv did not see fibrin thrombi
in the glomerular capillaries, because no mention is made of such an
occurrence. Engel reports the observation of five cases of chronic nephri-
tis accompanied by glomerulitis with the presence of fibrin threads in the
capsular space. These threads gave a positive Weigert's staining reac-
tion. Nothing, however, is said about the presence of fibrin in the
glomerular capillaries, Kahlden describes a case of post-scarlatinal
nephritis with complete anuria, in which he observed an obliteration of
the glomerular capillaries by a fibrillar and granular material which
he considered to be typical fibrin. The glomerular fibrin thrombi were
continued into the vasa afferent ia and efferentia ,and frequently beyond
these into the arteriola recta. However, Kahlden was not successful in
staining the thrombi satisfactorily by Weigert's method, as his tissues
had all been fixed in Flemming and in Mueller's fluids. Friedlaender,
according to the preceding writer, previously described a type of post-
scarlatinal glomerulo-nephritis wliich manifests itself from three to four
weeks after scarlatina and which is characterized by oedema, albuminuria,
oliguria, or even anuria. The microscopic examination of the kidneys
in such cases shows glomerular capillaries changed into solid, sausage-
like masses, making it scarcely possible to difl'erentiate the wall of the
capillary from its contents. Whether Friedlaender looked upon this
thrombotic material as fibrin does not appear. Ernst found fibrin in the
capsular space of the glomeruli and also in the interior of the hyaline
tube casts in cases of nephritis. No mention is made of fibrin thrombi
in the glomerular vessels. Eibbert, speaking of glomerulo-nephritis in
one place and hyaline thrombosis in another, mentions hyaline fibrin
thrombi as occurring occasionally in the glomerular capillaries. Tschis-
towitsch, one of the most recent writers on obliteration and hyaline
degeneration of the glomeruli, does not mention hyaline fibrin thrombosis.

From a review of the literature on the subject of glomerular
clianges in nephritis it would certainly appear that hyaline fibrin
thrombosis of the glomerular capillaries is a rather rare occur-

137

rence, which has been more fully described only in connection
with late post-scarlatinal nephritis and with swine plague by
Welch. It would probably be a thankless task here to attempt an
explanation of the formation of hyaline filjrin thrombi in the
vessels of the kidneys and of other organs, particiilarly in the
infected lymph glands in plague. Indeed, such an attempt at
explanation would open up the whole question of blood coagulation
and of fibrin formation inside and outside the blood vessels. Loeb
has quite recentl}^ published an experimental contribution to this
subject With reference to thrombosis and the formation of fibrin-
ous exudates he expresses the view that after the removal of the
vascular endothelium the specific substances causing coagulation are
extracted from the tissues. The ferments acting upon fibrinogen,
held in colloidal solution, precipitate it in the form of fibrin. How-
ever, in most of our renal sections, in which hyaline fibrin throm-
bosis has been seen in the glomerular vessels, the vascular epithelium
was to all intents and purposes morphologically intact and well
preserved. It is of course not at all unreasonable to suppose that
the plague toxines acting as they appear to do in particular upon
the kidneys, so damage the vascular epithelium that it becomes
pervious to the coagulating ferments, before any morphologic
changes indicate a serious functional disturbance.

THE URINE IN PLAGUE.

That the kidneys are profoundly afilected in plague is illus-
trated not merely by the findings on the post-mortem table and by
microscopic examination of the sections but by the clinical history
of the disease.

The Germ.in commission reports that it found albumen in the urine
in most cases of plague in which a urine examination was made, while
hyaline and granular casts and few or numerous blood corpuscles were
seen occasionally. Calmette and Salembini state that it is only in grave
cases that the urine is diminished or entirely suppressed. They sometimes
saw bloody urine, and always found it very acid and with traces of
albumen. Aoyama states that the albuminuria is generally moderate.
Bitter formd albimien in most cases, generally very moderate in amount;
but in fatal cases it was invariably present. Yamagiwa found albumen
only rarely. The Austrian commission examined the urine in fortj^-five
cases and found albumen present in all of those where repeated examina-
tions were made. The most extensive urine examinations in plague have
been made by Cathorn in India. She found albumen absent in only 24.
or 7 per cent, out of 341 fatal cases; while in 256 nonfatal cases it was

138

absent in 64, or 25 per cent of them. In some of our cases, with a
septico-pyemic dissemination of the virus, we have found an extensive
infection of the kidneys with plague bacilli; and the conclusion is justified
that the bacilli must be abimdant in the urine in such cases. In fact
in articles on plague one frequently finds the statement that the urine
generally contains bacilli; yet exact observations on this point have thus
far been very meager.

The German commission reports that it found plague bacilli in the
urine in only two cases. The urine both from plague patients and from
post-mortem cases usually was foimd free from these organism. The
Austrian commission frequently found numerous plague bacilli in the
kidneys, but encountered them in only five out of seventeen different spec-
imens of urine obtained post-mortem from plague cases. The Indian com-
mission examined sixty specimens of urine by cultural methods and found
the plague bacilli three times. Five other specimens were examined by
inoculation into guinea pigs; in one case only did an animal develop
plague.

These results obtained from the bacteriologic examination of
urine in plague are well in accord with our own histologic observa-
tions. The bacilli were as a rule found in the renal tissue only in
moderate numbers and in such situations that their appearance
in the urine was not at all likely. Onl_y when found in the capsular
space of the glomeruli may we safely suppose them to have been
present in the urine also. However, since one can not know inter
vitam whether an infection of the kidneys exists or not, it is well
always to treat the urine in plague as a possible source of infection.
The same rule applies to feces, which likewise, as the histologic
study of the stomach and intestines teaches, may sometimes contain
plague bacilli.

However we may here insert that the presence of plague bacilli
in the feces must be still more exceptional than their appearance in
urine.

The German commission was never able to demonstrate them in the feces
either by culture or by animal inoculation. The Indian commission, after
giving a detailed account of its work on the attempted detection of
plague bacilli in the feces, says: "The results of the above series of
examinations may be summarized in the statement that the plague
bacillus as yet has not in any case been isolated from human feces. Such
a negative result is, however, of very little account in view of the fact
that it is, as we have seen, a matter of extreme difficulty to isolate by
cultural methods the plague bacillus from a material such as feces, in
which the bacillus coli and an infinity of other bacteria are to be foimd."

The pelves of the kidne3^s, in intensely hemorrhagic cases, occa-
sionally contain a considerable amount of blood. In such cases the

139

bladder may likewise contain bloody urine or even blood coagula.
Like the mucosa of the pelves, that of the ureters and the bladder
occasionally shows petechia and ecchymoses.

The suprarenals are generally somewhat swollen, enlarged, soft-
ened, and congested, and darker in color than normal. We have
not found any marked histologic changes in them, aside from
dilatation and engorgement of the capillaries, conditions which are
particularly noticeable in the interfascicular capillaries of the
cortex.

THE LIVER AND THE GALL BLADDER.

The liver is generally of normal size, though it may be slightly
enlarged. In those cases where we have found a decrease it was
clearly not due to the plague infection but to inorbid conditions
previously existing. The capsule is smooth and tense ; its external
color is deep purplish-blue or purplish-pink. Evidences of a minor
or more pronounced degree of fatty degeneration are rarely miss-
ing. Alternating with the general purplish color we find areas
which are grayish-white or grayish-yellow. The cut surface shows
a brownish-red or ocher-yellow color according to the degree of
fatty infiltration and degeneration, and the veins discharge much
blood. In septico-pyemic cases we encountered necrotic, soft,
grayish-white foci. These may also shine through the surface and
may have been noticed before the organ is cut into. The liver
lobules are either distinct or more or less indistinct; and their
boundaries may frequently be even more distinct than under normal
conditions, which is due to the fact that interacinous, periportal,
inflammatory foci are often encountered in the liver in cases of
plague. They were found in cases Nos. 1, 2, 3, 7, 8, 9, 10, 14, 16,
17, and 20. The microscopic examination, aside from these foci,
further shows dilated, engorged capillaries. The parenchyma cells
are finely or coarsely vacuolated or in a condition of cloudy swell-
ing or more or less complete granular degeneration. In uncom-
plicated cases of bubonic plague the parenchyma cells are not
profoundly changed; but in septico-pyemic cases the change is
generally quite profound. The necrotic foci, if present, contain
large numbers of bacilli and frequently show capillaries more or less
completely occluded by metastatic emboli. The cells in this neigh-
borhood are in a condition of complete coagulation necrosis, which
extends beyond the groups of bacilli into the adjacent tissues.
Phagocytic, proliferated endothelia are sometimes seen in the liver.

140

The gall bladder is generally normal; but it may sometimes be
profoundly chauged, showing numerous subserous hemorrhages and
a comj^letely oedematous and almost gelatinous condition of the wall.
The bile itself varies from a normal consistency and golden-yellow
color to a pitchy condition and almost black color. The serosa of
the gall bladder, like that of the liver, occasionally shows extensive
ecchymotic spots.

We have not encountered any marked macroscopic or microscopic
changes in the pancreas.

THE STOMACH AND THE INTESTINES.

The stomach and the intestines are generally markedly affected
in plague. Petechige and ecchymoses are found both in the serosa
and in the mucosa. Particularly the gastric mucosa is generally
in a hemorrhagic condition. The petechiae often extend into the
duodenum and occasionally even into the esophagus. Microscop-
ically, the mucosa of the stomach always shows greatly dilated
interglandular vessels and frequently hemorrhages between the
glands and into the uppermost layers of the mucosa or even upon its
free surface. Plague bacilli were found in these areas only in
septico-pyemic cases. The upper layers of the mucosa are often
necrotic; and the cells of the peptic glands, even where the mem-
brane is still fairly intact, show evidence of nutritive disturbance
(multinuclear cells). The small and large intestine in general
frequently show a great congestion of the mucosa and serosa with
petechia and ecchymoses. In one case submucous blood cysts were
found in the large intestine ; these were probably due to the plague
infection, as other, higher parasites could not be demonstrated in
them. In a considerable proportion of our material the intestinal
follicles were more or less swollen, viz, moderately in cases Nos. 6,
7. 15, and 17, and markedly in cases i^os. 1, 5, and 12, and highly
in case No. 2. In the other cases the intestinal lymph follicles
were normal.

STEPS IN ESTABLISHING THE POST-MORTEM DIAGNOSIS

OF PLAGUE.

We shall now mention briefly, but systematically, all observa-
tions and experiments which will in a given case of suspected
fatal plague enable us to come to a definite and conclusive diagnosis.
However, it must be borne in mind that there are some exceptional

141

cases in whie]i a diagnosis is impossible. When a plague infection
has run its course without having in itself killed the patient, he
may nevertheless succumb to a secondary pyogenic complication, to
parenchymatous degeneration of the internal organs or to exhaus-
tion due to toxemia, any one of which may carry off the victim
after the plague bacilli have disappeared from the primary bubo
and from the system at large. Of course such exceptional cases
are of no great epidemiological importance, since a spread of plague
can not occur if no more bacilli are present. In the great majority
of fatal cases of human plague the post-mortem diagnosis, to one
familiar with the disease and with the ordinary technique of
bacteriological investigation offers no particular difficulties. The
diagnosis of plague in rat cadavers which are much decomposed is
a matter of much greater difficulty, hut in this article this is a
subject with which we not concerned.

The report of the Indian Plague Commission (Vol. V, p. 442)
gives the following description of the body of a patient dead of
plague :

The body, if undisturbed, is stated to be generally lying on one side,
with the knees flexed, and the head slightly bent on the chest. The
skin in dry, and in a few cases petechise and purpuric spols may be
seen; the muscles are soft, as the rigidity of death is delayed; the features
retain a fixed, anxious appearance; the eyes are half closed and sunken,
Avith the pupils dilated; and the tongue is swollen, and although it
sometimes has the appearance displayed during life, not unusually it is
covered with a dry, almost horny dark or yellowish-bro^\Ti and cracked
fur. In pneumonic cases, the body seems especially shrunk and collapsed
and has a livid aspect, and blood-stained sputum is often found adherent
to the lips. Our attention was drawn by Captain Elphink, I. M. S., to
the existence of cedoma, extending over the front and sides of the chest,
the abdomen, and the upper part of the arms, which had been observed
by him and by Captain Chaytor-White, I. M. S., in all plague corpses,
and was believed to occur immediately before death. If this condition
is generally present, it would be valuable as an aid in determining if
death had been caused by plague, and especially in cases where no
buboes are present. It has not, however, been observed bj' the great
majority of those who in India have had the opportunity of seeing large
numbers of fatal cases, both before and after death.

This guide to the post-mortem diagnosis of ])lague is evidently
not intended for the pathologist performing a necropsy, but for
the general practitioner or the layman-sanitary inspector of India.
But we seriously doubt whether anybody will be materially assisted
in a plague diagnosis by so vague a description as that given

142

above. The general oedema which is mentioned we have never
seen in any of our plague cases.
The following are the steps in a systematic plague necropsy :

(1) External inspection of the body. — As the most characteristic
points brought out by the external inspection of a body dead of
plague we would mention the following: The bubo is generally
present in the femoral, the axillar}^ or the cervical region, and con-
sists of a rather firm, doughy swelling over which the skin is
generally adherent while the surrounding tissue is markedly oede-
matous. In the neighborhood of the bubo may be seen an ulcer or
a carbuncle with extensive necrosis. As a whole the surface of the
body is frequently cyanotic; skin eruptions, petechias, and
ecchymoses are commonly observed. A dark, blood-tinged, foamy,
serous fluid always oozes from the nostrils of a plague body when
it is turned over. This is due to the great congestion and oedema
of the lungs, which we have never failed to observe in any of our
cases.

(2) The dissection of the body shows the multiple, interstitial
subserous and submucous hemorrhages, the general congestion of
the organs, the spleen tumor, the parenchymatous degeneration of
the kidneys, and the lobular consolidation in pneumonic cases,
described in detail above.

(3) During the post-mortem examination inoculations of agar
and salt-agar tubes or plates and gelatin plates are to be made
from the bubo, or as the case may be, from the consolidated areas
of the lungs, the spleen, the heart's blood, a;id other organs,
particularly if they show areas of focal necrosis.

(4) Preparations of smears from the same locations are to be
made on slides, which as soon as air dry are immersed in absolute
alcohol.

(5) Pieces of tissue from the primary focus (lymph glands or
lungs), from the spleen, and from the necrotic foci, are to be col-
lected and placed in sterile, empty test tubes or Petri dishes.

(6) Pieces of tissue are to be fixed in Zenker's solution for the
subsequent histologic examination.

(7) Animal inoculations. — After the termination of the autopsy
the pieces of tissue preserved in sterile receptacles are to be used
for inoculation into guinea pigs. A number of these animals are
infected by the cutaneous method (Gohn and Albrecht) by rubbing
some of the juice from the bubo (or lung) and the spleen on the

14

■J

shaved abdomen. Other animals should receive subcutaneous and
intraperitioneal inoculations of the suspected material triturated
with sterile phj^siologic salt solution.

(8) After twenty-four hours the tube and plate cultures are
to be examined with the naked eye^ with the aid of the magnifying
glass and in stained cover-glass preparations. The animals like-
wise are to be examined. Some of those which have received
intraperitoneal injections are liable to succumb to the plague infec-
tion after twenty-four hours.

Martini has worked out a special method in the examination of guinea
pigs infected cutaneously. Since this method often enables us to make a
definite diagnosis in doubtful plague cases after forty-eight hours, it is
to be recommended. His method is as follows:

(a) The material suspected of containing the plague bacilli is triturated
with about three times the quantum of sterile bouillon. This emulsion
is rubbed with the back of a knife on the shaved abdomen of several
(five or six) guinea pigs.

(b) After twenty-four hours the guinea pigs are examined for swollen
lymph glands, and if any are found, their juice is drawn with a sterile
syringe and inoculated into agar tubes, and also examined in smears.

(c) If what appear to be plague bacilli are found in the smears, two
rats are inoculated intraperitoneally with tlie juice obtained from the
enlarged gland of the guinea pigs.

(d) The cultures obtained from the juice are examined macroscopically
and microscopically and tested with an antiplague serum of known
agglutinating power.

The agglutination test can not be made, it should here be stated expressly,
with antiplague sera selected "at random," because some have little
or no agglutinating power, as has been repeatedly pointed out by several
observers, including the Indian Plague Commission. (Vol. V, p. 68 of
report. )

Kolle and Martini recommend the desiccated antiplague serum of the
Pasteur Institute for the agglutination test. The dry fine powder is
first dissolved in ten times its weight of sterile distilled water (I gram
to 10 cubic centimeters. The solution is complete after several hours,
whereupon the further dilutions necessary for tlie tests can be prepared. It
is found that this dry serum will agglutinate genuine plague cultures, and
only those, in dilutions of from 1:1,000 to 1:6,000. The less virulent the
plague culture the greater the agglutinating powder of the dry serum;
and vice versa, the more virulent the cultures, the lesser the agglutinating
power.

Zlatogorofi", who studied the question as to how long plague bacilli
remain alive and virulent in cadavers under various conditions of tem-
perature and moisture, maintains that the cutaneous method of Golm
and Albrecht for infecting guinea pigs, is absolutely reliable only as long
as the organs do not contain any considerable number of putrefactive and

144

other microbes. For diagnostic purposes in the case of old cadavers he
therefore recommends a pernasal inoculation, which he practiced in the
following manner: The lower part of one of the nasal cavities of a
guinea pig is slightly wounded with a pair of sharp forceps or a needle,
however, in such a manner that very little blood is drawn. A small
piece, preferably of the spleen, is then grasped in fine forceps and in-
troduced into the side where the slight trauma has been produced, after
which it is well rubbed into the masal mucosa by rotatory motions of
the forceps. This method is certainly somewhat objectionable on account
of the danger of inducing a fit of sneezing in the animal operated upon,
with uncontrollable dissemination of the plague material. Zlatogoroff
himself considers this energetic procedure a "misstand," as he expresses
it, but he confesses that it is indispensable, as otherwise the test may
be negative in the presence of virulent plague bacilli. It also appears
that this author has not ruled out the possibility of producing by his
method in guinea pigs a disease which might simulate plague, a fallacy
which, according to all the testimony obtained in this matter, is impos-
sible by the cutaneous method. Zlatogoroft''s investigation, at any rate,
was not made with material derived from human cadavers, but with
pieces of organs from the decomposed bodies of animals infected experi-
mentally with plague. Since his publication has appeared after our
report was practically finished, we have not taken an opportunity to
try his method, and hence can not recommend it.

We do not wish to create the impression that all the cultural
and inoculation experiments detailed above are necessary to arrive
at a reliable diagnosis of plague in each suspected case. On the
contrary, one familiar with plague can generally make a diagnosis
after the termination of the necropsy, as soon as the smears from
the organs have been examined microscopically. But in obscure
cases all of the steps mentioned above may be necessary, and none
of them should be omitted when a first-suspected case is to be
diagnosed in a plague-free locality where an incontestable diagnosis
is a necessity in justifying the protective and restrictive measures
which should be instituted in order to prevent the spread of an
infectious disease which at times many assume such destructive
pandemic proportions.

14o

REFERENCES TO LITERATURE.

The following is a list, an'anged alphabetically by authors, of the
articles to which reference has been made in the text. A few
of these articles, marked with an asterisk (*), have not been acces-
sible in the original :

Albrecht and Gohn. * Ueber die Beulenpest in Bombay, Wien. 1898
and 1900.

AOYAMA. Mittlieilungen ueber die Pestepidemie im Jahre 1894 in Hong-
kong. Mittheil. der mediz. Fakultaet der Kaiserl-Japan. Univer.,
zu Tokio. 1895, No. 2, Vol. III. Centralbl. f. Bakf., 1896, Vol.
XIX, p. 481.

Babes and Livadite. Ueber einige diircli den Pestbacillus verursachte
histologischen Veraenderungen. Virchov^s Archiv. 1897, Vol. CL,
p. 343.

Bakeb. a Revision of American Siphonaptera, etc. Smithsonian Insti-
tution. Proc. U. S. yat. Museum. Vol. XXVII, p. 355.

Baxdi and Stagnitta. Die Verbreitung der Bubonen-pest durcli den
Verdaumigsweg. Zeitschr. f. Hygiene, etc. 1898, Vol. XXVIII,
p. 261.

Barker. On tlie Clinical Aspects of Plague. The Amencan Journal of
the Medical Sciences. 1901, Vol. CXXII, p. 377.

Baumgartex. Ueber die Patliologisch-liistologische Wirkimg des Tuberkel-
bazillus. Berl. Klin. Wochenschrift. 1901, No. 44, p. 1101.

Bazaroff. La Pneumonie pesteuse Experimentale. Annales de Pasteur.
1899, Vol. XIII, p. 385.

Bitter. Ueber die Haffkin'sche Schutzimpfung gegen Pest, etc. Zeitschr.
f. Hygiene. 1899, Vol. XXX, p. 448.

Boehm. Beitrag zur pathol. Anatomie der Malpigliischen Koerperelien der
Niere. Virchow's Archiv. 1897, Vol. CL, p. 52.

Cairxs. On the Agglutinating Property of Blood Serum in Cases of Plague.
London Lancet, June 22 1901. 1901, p. 1746.

Calmette and Salimbexi. La Peste Bubonique. Annales de Pasteur.
1899, Vol. XlII, p. 865.

Calvert. Bubonic Plague. Circulars on Tropical Diseases. ^lanila, May,
1901.

Plague Bacilli in the Blood. Centralbl. f. Bakteriol. 1 Abth., Origin.,

Vol. XXXIII, No. 4, p. 247.

Caxtlie, Jas. * The Phigue. The Pract it tuner. November. 1899, p. 522.

Childe. L. F. The Pathology of Plague. Brit. Med. Journal. 1898, Sep-
tember 24, p. 859.

Remarks on the Occurrence of Plague Pneumonia. Brit. Med. Journal.

1897. p. 1215, No. 1898.

CoRTHORX. Albuminuria in Plague. Brit. Med. Jourmil. 1901, Vol. II,
p. 671.

25483 10

146

CuERY. Report on the Plague in Manila. Boston Med. and Surg. Journal.

1901, No. 12. CeniralU. f. Bald. I Abtli., Vol. XXXI, p. 7, 1902.
Deutsche Pest Commission.* (Galfky, Pfeiffer, Sticker, Dieudonn6.)

Mittheilungen aus Bombay. Deutsche Mediz. Wochenschrift, 1897,

April, 22, No. 31, p. 501.

Bericht ueber die Thaetigkeit der D. P. Commission. Arbeiten a. d.

Kaiserl. Gesundheitsamte. 1899, Vol. XVI.
DiEUDONNfi. Article "Pest" in Kolle und Wassermann's Handhuch der

pathogenen Microorganismen. Jene, 1903. Vol. II. p. 474.
DuEBCK. Ueber pathologisch-anatomische Befunde bei der Lungenpest.

Muench. mediz. Wochenschr. 1902, p. 550.
Engel. Glomerulitis adhaesiva. Virchoto's Archiv. 1901, Vol. CLXIII,

p. 209.
Ernst. Ueber das Vorkommen von Fibrin in Nieren-cylindern. Ziegler's

Beitrdge. 1893, Vol. XII, p. 553.
Fichera and Scaffidi. Beitrag zur pathologischen Histologie der Glom-
eruli. Virchow's Archiv. 1904. Vol. CLXXVII, p. 63.
'Flexner. The Pathology of Bubonic Plague. The American Journal of

Medical Sciences. 1901, Vol. CXXII, p. 396.
Friedlaender. * Ueber Nephritis scarlatinosa. Fortschritte der Medizin.

Vol. I, p. 84.
Galli-Valerio. Les Puces des Rats et des Souris. Centralbl. f. Bakt.

1900, Vol. XXVII, p. I.
Quelques Observations sur la IMorphologie du Bacterium Pestis.

Centralbl. f. Bakt. 1900, Vol. XXVIII, p. 842.

The Part Played by Fleas of Rats. Journ. Trop. Med. 1902, p. 33.

Goemans. * La Capsule de Bowman dans ITnflammation Chronique des

Reins. Recueil des Travaux Anatomo-pathologique du Laboratoire
Boerhaave. Leyden, 1899.
GOTSCHLICH. Die Pest-Epidemie in Alexandrien in Jahre 1899. Zeitschr.
f. Hygiene. 1900, Vol. XXXV, p. 195.

Ueber wochenlange Fortexistenz lebender virulenter Pestbazillen im

Sputum geheilter Faelle von Pestpneumonie. Zeitschr. f. Ili/gicne.

1900, Vol. XXXII, p. 402.
Hankin. Note on the Relation of Insects and Rats to the Spread of

Plague. Centralbl. f. Bakt. 1897, Vol. XXII, p. 437.
Hankin and Leumann. A iMethod of Rapidly Identifying the Microbe

of Bubonic Plague. Centralbl. f. Bakt. I Abth, 1897, Vol. XXII,

p. 438.
Hanseman. Zur pathologischen Anatomie der ^lalpighischen Koerperchen

der Niere. Virchow's Archiv. 1887, Vol. CX, p. 52.
Havelburg. Die Pest in Brazilien. Bol. Klin. Wochenschr. 1901, Vol.

XXXVIII, p. 530.
Herzog and Hare. Does Latent or Dormant Plague Exist Where the

Disease is Endemic? Bulletin No. 20, Dept. of the Interior, Bureau

Govt. Laboratories, Biological Laboratory. Manila, P. I., 1904.
HOSSACK. Tlie Diagnosis of Plague. Brit. Med. Journal. 1900, Novem-
ber 24, vol. 2, p. 1486.

147

Jennings. A Manual of Plague. London. 1903.

Indian Plagite Commission. Report of tlie. Five volumes. London. lOOL

Israel. Die anaemische Nekrose der Nierenepithelien. Virchow's Archiv.

1891, Vol. CXXllI, p. 310, 327.
IvAHLDEN. Ueber die Glomerulitis bei Scharlach. Ziegler's Beitraege zur

Pathol. Anatomie. 1894, Vol. XV, p. 602.
Kellogg and Kinyoun. * The Plague. Occidental Med. Times. 1900

and 1901, Vol. XIV, XV.
KiTASATO. Preliminary Note on the Bacillus of Bubonic Plague. Lancet.

1894, Vol. II, p. 428.
Klebs. Haudbuch der pathologischen Anatomie. Berlin. Vol. I, Pt. 2,

p. 644.
Kolle. Bericht der Peststation. Zeitschr. f. Hygiene. 1901, Vol. XXXVI,

p. 397.
KoLLE and Martini. Ueber Pest. Deutsche mediz. Wochenschr. 1902,

Vol. XXVIII, p. 46.
KoNSTANZOFF. Beziehung der Bubonenpest zu anderen Formen der
haemorrhagischen Septikaemie. Centralbl. f. Bakt. 1901, Vol.
XXIX.
KossEL and Overbeck. Bakteriologische Untersuchungen ueber Pest.
Arheiten aus dem Kaiserl. Gesundheitsamte. 1901, Vol. XVIII,
p. 122.
La Bonadiere and Xanthopltlides. * De I'Existence dans le Corps d'un
Moustique de la Chambre d'un Pestifere. Annales d'Hygiene pub.
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L^eber die Veraenderungen der Glomeruli bei der Nephritis nebst

einegen Bemerkungien. Virchow's Archiv. 1879, Vol LXXVI, p. 85.
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Archiv. Vol. CLXXVI, p. 10.
Loir. * Revue Scientifique. 1900, No. 13, p. 395.

LusTiG and Zardo. Beitrag zum Studium der feineren Grewebsver. bei
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Maasen. Die teratologisehen Wuchsformen ( Involutionsformen ) der Bak-
terien und ihre Bedeutung als diagnostisches Hilfsmittel. Arbeiten
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Museholi). Die Pest, und ihre Bekaempfung. Berlin, 1901.

148

Now. The Bacteriology of Bubonic Plague. The American Journal of

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XXVIII, p. 165.

Ueber die Pestepidemie in Formosa. Centralhl. f. Bakt. 1897, Vol.

XXI, p. 769.
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Med. and Surg. Reports of the City of Boston Hospital. 10th ser.,

1899.
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149

WiLM. * Hygienische Rundschau. Nos. 5, 6, 1897.

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