INFLAMMATION OF THE EXTERNAL ACOUSTIC MEATUS 303
proportions of these organisms vary with the geographical area, Ps, pyocyanea
being commonest in tropical and subtropical regions.
SYMPTOMS. At an early stage pain in the ear and discharge from the meatus
are commonly present. Pain is usually severe in furunculosis, aural herpes
and the acute primary stage of diffuse otitis externa being preceded in the
latter by a hot burning sensation and followed by a thin serous discharge
which may become thicker and more profuse as the condition develops.
When discharge is present a swab should be taken to determine the organisms
and their sensitivity to antibiotics. If the discharge has a sticky mucoid
content an underlying otitis media must be suspected. Itching is a prominent
symptom in seborrhoeic dermatitis, drug sensitivity, neurodermatitis and
otomycosis. Conductive deafness results from obstruction of the meatus
by oedema of the walls and accumulated debris or discharge. In cases of
chronic diffuse otitis externa thickening of the meatal skin causes a perma-
nent meatal stenosis so that small amounts of wax and epithelial debris
may give rise to deafness. Fissuring of the skin around the meatal introitus
is associated with seborrhoeic dermatitis and eczema. Furunculosis of the
posterior meatal wall may be accompanied by retro-auricular oedema with
erection or protrusion of the auricle.
MANAGEMENT. Cleansing of the skin of the external meatus is necessary.,
All discharge and epithelial debris must be carefully and gently removed,
first so that the drumhead may be inspected and secondly to allow local
therapeutic applications to gain contact with the skin of the meatus. Cleans-
ing in the tender ear may be done by gentle irrigation with a bland solution,
such as isotonic saline at 38 °C, and when inspection has shown that the
meatus is clean it is carefully dried with lightly dressed cotton-wool mops
on a wire carrier. Further otoscopic examination should be done to visualize
the drumhead and to ensure that no debris remains in the antero-inferior
meatal recess. Failure to clear this pocket may result in prolonged treatment
and recurrences. In dry, scaly and crusted ears cleansing may be helped by
the use of mops dipped in sterile liquid paraffin. Trauma to the meatal skin
must be avoided and treatment by trained staff is necessary.
Furunculosis. Boils (furuncles) are due to a staphylococcal infection of
hair follicles or sebaceous glands which are present in the skin of the outer
cartilaginous part of the external meatus. They may develop in the super-
ficial layers of the skin or may be more deeply seated. A boil may occur
as a single lesion or as multiple lesions confined to the ear or associated
with boils elsewhere in the body. They commonly recur particularly hi
debilitated individuals and in diabetics.
Furuncles produce severe pain in the ear and tenderness in the region of
the meatus at an early stage. Swelling of the meatal walls may occlude the
meatus thus causing deafness. The superficial infection may be seen as a
small, red, circumscribed and very tender swelling on the skin of the meatus.
Deep infection is more diffuse and the skin initially shows no significant
change although the area may be tender on gentle pressure. When a boil is
situated on the anterior or inferior meatal wall chewing movements of the
jaw cause increased pain and swelling of the lower eyelid may be present.
If the boil is on the posterior wall the swelling may cause protrusion of the
auricle and obliteration of the postauricular sulcus by oedema. Infection
may spread to lymph glands either anterior to the auricle or below the tip