Health Encyclopedia

Malignant otitis externa

Definition

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

Alternative Names

Osteomyelitis of the skull; Otitis externa - malignant

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.

Symptoms

Drainage from the ear - yellow, yellow-green, foul smelling, persistent
Ear pain - felt deep inside the ear and may get worse when moving head
Hearing loss
Itching of the ear or ear canal
Fever

Signs and tests

A doctor will look into your ear for signs of an outer ear infection (otitis externa). The head around and behind the ear may be tender to touch. A nervous system (neurological) examination may show that the cranial nerves are affected.

If there is any drainage, the doctor may send it to the lab for a culture. The purpose of the culture is to look for bacteria or fungi, usually the bacteria Pseudomonas.

To look for signs of a bone infection next to the ear canal, the following tests may be performed:

Treatment

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.

Antibiotics that are effective against the microorganism are given for long periods of time. They may be given through a vein (intravenously), or by mouth. Antibiotics should be continued until scans or other tests show that inflammation has gone down.

Occasionally, surgery to remove dead or damaged tissue (surgical debridement) in the skull is needed.

Expectations (prognosis)

Malignant otitis externa usually responds to long-term treatment, but it may return in the future.

Complications

Damage to the cranial nerves, skull, or brain
Return of infection, even after treatment
Spread of infection to the brain or other parts of the body

Calling your health care provider

Call for an appointment with your health care provider if:

You develop symptoms of malignant otitis externa
Symptoms continue despite treatment
You develop new symptoms

Go to the emergency room or call the local emergency number (such as 911) if you have:

Prevention

To prevent an external ear infection:

Dry the ear thoroughly after it gets wet.
Avoid swimming in polluted water.
Protect the ear canal with cotton or lamb's wool while applying hair spray or hair dye (if you are prone to getting external ear infections).
After swimming, place 1 or 2 drops of a mixture of 50% alcohol and 50% vinegar in each ear to help dry the ear and prevent infection.

Treat acute otitis externa completely. Do not stop treatment sooner than your health care provider recommends. Following your doctor's plan completely will reduce the risk of malignant otitis externa.

Review Date:10/10/2008
Reviewed By:Alan Lipkin, MD, Otolaryngologist, Private Practice, Denver, Colorado. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997-A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

The Agency for Health Care Administration (Agency) and this website do not claim the information on, or referred to by, this site is error free. This site may include links to websites of other government agencies or private groups. Our Agency and this website do not control such sites and are not responsible for their content. Reference to or links to any other group, product, service, or information does not mean our Agency or this website approves of that group, product, service, or information.

Additionally, while health information provided through this website may be a valuable resource for the public, it is not designed to offer medical advice. Talk with your doctor about medical care questions you may have.