CHAPTER 13
ACUTE SINUSITIS

Acute inflammation of the paranasal sinuses is due in most instances to
extension of an infection in the nasal cavity, and is only very occasionally
blood-borne. The sinuses may be involved singly, or two or more may
become infected. The most common cause is an acute rhinitis, especially
during a virus epidemic, but it may follow the acute infectious diseases,
infections of the pharynx or tonsils, dental infections such as apicitis or apical
abscess, or dental extraction should the floor of the maxillary sinus be
ruptured..Injury to the facial bones, operations on the nose, bathing and
particularly diving may result in sinusitis. Obstruction to the normal aeration
of, or drainage from, a sinus because of a deviated nasal septum predisposes
to sinus infection.

BACTERIOLOGY. The paranasal sinuses are probably bacteriologically sterile
in normal conditions of health, although a healthy nasal cavity may contain
micro-organisms. Acute infections are generally primarily virus in origin, the
rhinovirus, para-influenzal viruses, ECHO viruses, Coxsackie viruses and
respiratory syncytial viruses being the most common. Secondary infection
occurs from pyogenic organisms such as pneumococci, streptococci, staphylo-
cocci, H. influenzae, M. catarrhalis, B. Friedldnder, Esch. colt, B. proteus and
diphtheroids. In dental infections B. dentalis and B^necrodentalis may also be
present. Anaerobic organisms are not uncommonly found in the pus from
infected sinuses.

PATHOLOGY. An acute sinusitis may be catarrhal or suppurative, the
difference being one of degree. A catarrhal infection results in submucosal
oedema with a moderate leucocytic infiltration and only slight alteration in the
superficial epithelium. The discharge is mucoid. In the suppurative variety
there may be little oedema, but there is considerable leucocytic infiltration and
the surface epithelium may disappear or be subject to an extensive metaplasia.
The discharge is mucopurulent or frankly purulent. Obstruction of the ostium
usually occurs at the catarrhal stage and interferes with the drainage from the
sinus, allowing the infection to increase in virulence and perhaps spread
through the periosteum to involve the bony walls.

SYMPTOMS. The symptoms vary in severity. In milder cases with a patent
ostium the symptoms are similar to those of the acute coryza which precedes
the sinus infection so that it may be unrecognized until it passes to the chronic
stage. There may be complaints of a feeling of fullness or tension in the
affected sinus, or even of a slight ache which is accentuated by stooping,
straining or coughing. There may be slight tenderness on pressure over the
affected sinus.

In the more severe type there are malaise and pyrexia. Headache and pain
are complained of, and there is a sensation of tightness in the sinus. The voice

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