The outer one-third of external acoustic meatus has skin with sebaceous glands, hair follicles, and sweat glands. The infection of hair follicle may result in formation of boil in the external ear. It is mostly caused by staphylococcus aureus.
Any condition that causes damage to skin of the external acoustic meatus is a risk factor of furuncle. Most common among them are trauma to ear, bad instrumentation, scratching of ear, skin diseases, seborrhea, swimming in contaminated water, and allergies. Diabetes is also common.
The presenting complaint is almost always pain. Since skin in external auditory canal is tightly adherent to the underlying perichondrium, the pus cannot spread in the plane which results in severe pain. The ear is tender to touch. Itching is also a common complaint. Associated symptoms are fever, malaise, headache, and conductive ear loss due to blockage of canal. Boil can burst and cause discharge; it relieves pain.
Furuncles in ear mostly heal spontaneously. Symptomatic treatment may be required. It includes relieve of pain and fever. Hot compresses are also beneficial. Antibiotics are administered in case of severe infection. If the boil enlarges, incision and drainage may be imperative.
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