Malignant otitis externa is a disorder that involves infection and damage of the bones of the ear canal and at the base of the skull.
Malignant otitis externa is caused by the spread of an outer ear infection (otitis externa) also called swimmer's ear. It is not common.
Risks for this condition include:
External otitis is often caused by bacteria that are hard to treat, 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 swelling may damage or destroy the bones. The infection may affect the cranial nerves, brain, or other parts of the body if it continues to spread.
Your health care provider will look into your ear for signs of an outer ear infection. The head around and behind the ear may be tender to touch. A nervous system (neurological) exam may show that the cranial nerves are affected.
If there is any drainage, the provider may send a sample of it to the lab. The lab will culture the sample to try to find the cause of the infection.
To look for signs of a bone infection next to the ear canal, the following tests may be done:
The goal of treatment is to cure the infection. Treatment often lasts for several months, because it is difficult to treat the bacteria and reach an infection in bone tissue.
You will need to take antibiotic medicines for a long period of time. The medicines may be given through a vein (intravenously), or by mouth. Antibiotics should be continued until scans or other tests show the inflammation has gone down.
Surgery to remove dead or damaged tissue (surgical debridement) in the skull may be needed in some cases.
Malignant otitis externa most often responds to long-term treatment, especially if treated early. It may return in the future. Severe cases may be deadly.
Complications may include:
Call your provider if:
Go to the emergency room or call the local emergency number (such as 911) if you have:
To prevent an external ear infection:
Treat acute otitis externa completely. Do not stop treatment sooner than your provider recommends. Following your provider's plan and finishing treatment will lower your risk of malignant otitis externa.
Reviewed By: Sumana Jothi, MD, specialist in laryngology, Assistant Clinical Professor, UCSF Otolaryngology, NCHCS VA, SFVA, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.