Malignant external otitis is a dangerous infection of the external ear that has spread to the temporal bone (the skull bone that contains the ear canal), the middle ear, and the inner ear.
Malignant external otitis occurs mainly in older adults with a weakened immune systemor diabetes. 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) can also cause this infection.
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)
Culture of discharge
Biopsy
The diagnosis of malignant external otitis is based on results of CT. Doctors also do a culture (a sample of the discharge is grown in a laboratory) to identify the microorganisms causing the infection. 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)
Corticosteroids applied to the outer ear
Sometimes hyperbaric oxygen therapy
Control of diabetes or other conditions that weaken the immune system
Repeated cleanings of the ear canal
Some people may be treated in a high-pressure oxygen chamber (hyperbaric oxygen therapy).
Meticulous control of diabetes is essential. If possible, doctors stop giving any drug that suppresses the immune system.
Although surgery is usually not necessary, repeated cleanings and removal of dead skin and inflammatory tissue (debridement) in the ear canal, done in a doctor's office, are necessary until the infection goes away.
