Definition of Malignant otitis externa:

Malignant otitis externa is a disorder involving inflammation and damage of the bones and cartilage at the base of the skull.

Causes, incidence, and risk factors:

Malignant otitis externa is caused by the spread of an outer ear infection (otitis externa, also called swimmer's ear). It is an uncommon complication of both acute swimmer's ear and chronic swimmer's ear.

Risks for this condition include:

• Chemotherapy
• Diabetes
• Weakened immune system

External otitis is often caused by difficult-to-treat bacteria such as pseudomonas. The infection spreads from the floor of the ear canal to the nearby tissues and into the bones at the base of the skull. The infection and inflammation may damage or destroy the bones. The infection may spread more and affect the cranial nerves, brain, or other parts of the body.