Malignant external otitis occurs mainly in people with a weakened immune system Overview of Immunodeficiency Disorders Immunodeficiency disorders involve malfunction of the immune system, resulting in infections that develop and recur more frequently, are more severe, and last longer than usual. Immunodeficiency... read more and in older people with diabetes Diabetes Mellitus (DM) Diabetes mellitus is a disorder in which the body does not produce enough or respond normally to insulin, causing blood sugar (glucose) levels to be abnormally high. Urination and thirst are... read more . Infection of the external ear, usually caused by the bacteria Pseudomonas, spreads into the temporal bone, causing severe, life-threatening infection. Methicillin-resistant Staphylococcus aureus (MRSA) has also been identified as a cause. Despite the name, the infection is not cancerous (malignant).
Symptoms of Malignant External Otitis
People with malignant external otitis have severe ear pain (often worse at night), a foul-smelling discharge from the ear, pus and debris in the ear canal, and usually decreased hearing. In severe cases, paralysis of nerves in the face and head may occur as the infection spreads along the base of the skull.
Diagnosis of Malignant External Otitis
Computed tomography (CT) scan
Culture of discharge
The diagnosis of malignant external otitis is based on CT scan results. Doctors also do a culture (a sample of the discharge is grown in a laboratory to identify the microorganisms). Often doctors need to take a small piece of tissue from the ear canal and examine it under a microscope (biopsy) to make sure that the symptoms are not caused by cancer.
Treatment of Malignant External Otitis
Antibiotics, typically given by vein (intravenous)
Sometimes hyperbaric oxygen therapy
Control of diabetes
Repeated cleanings of the ear canal
Typically, malignant external otitis is treated with a 6-week course of antibiotics given by vein. However, people with a mild infection may be treated with high doses of an antibiotic such as ciprofloxacin taken by mouth. Some people may be treated in a high-pressure oxygen chamber ( hyperbaric oxygen therapy Recompression Therapy Recompression therapy involves giving 100% oxygen for several hours in a sealed chamber at pressures higher than 1 atmosphere. (See also Overview of Diving Injuries.) Recompression therapy has... read more ). People who have extensive bone disease may require antibiotic therapy for a longer period.
Meticulous control of diabetes Diabetes Mellitus (DM) Diabetes mellitus is a disorder in which the body does not produce enough or respond normally to insulin, causing blood sugar (glucose) levels to be abnormally high. Urination and thirst are... read more is essential. If possible, doctors stop giving any drug that suppresses the immune system Some Drugs That Can Cause Immunodeficiency .
Although surgery usually is not necessary, repeated cleanings and removal of dead skin and inflammatory tissue (debridement) in the ear canal in the doctor's office are necessary until the infection goes away.