Definition of Malignant otitis externa:

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

• Malignant = harmful and invasive
• Otitis = ear infection and inflammation
• Externa = outer

Causes, incidence, and risk factors:

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

Persons with diabetes and weakened immune systems are particularly susceptible to malignant otitis externa.

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 adjacent tissues and into the bones at the base of the skull. The bones may be damaged or destroyed by the resulting infection and inflammation. The infection may further spread and affect the cranial nerves, the brain, or other parts of the body.