What is the definition of Malignant Otitis Externa?

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.

What are the alternative names for Malignant Otitis Externa?

Osteomyelitis of the skull; Otitis externa - malignant; Skull-base osteomyelitis; Necrotizing external otitis

What are the causes for Malignant Otitis Externa?

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:

  • Chemotherapy
  • Diabetes
  • Weakened immune system

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.

What are the symptoms for Malignant Otitis Externa?

Symptoms include:

  • Ongoing drainage from the ear that is yellow or green and smells bad.
  • Ear pain deep inside the ear. Pain may get worse when you move your head.
  • Hearing loss.
  • Itching of the ear or ear canal.
  • Fever.
  • Trouble swallowing.
  • Weakness in the muscles of the face.

What are the current treatments for Malignant Otitis Externa?

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.

Dead or infected tissue may need to be removed from the ear canal. In some cases, surgery may be needed to remove dead or damaged tissue in the skull.

What is the outlook (prognosis) for Malignant Otitis Externa?

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.

What are the possible complications for Malignant Otitis Externa?

Complications may include:

  • 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

When should I contact a medical professional for Malignant Otitis Externa?

Call your 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:

  • Convulsions
  • Decreased consciousness
  • Severe confusion
  • Facial weakness, loss of voice, or difficulty swallowing associated with ear pain or drainage

How do I prevent Malignant Otitis Externa?

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.
  • Maintain good glucose control if you have diabetes.

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.

Ear anatomy


Araos R, D'Agata E. Pseudomonas aeruginosa and other pseudomonas species. In: Bennett JE, Dolin R, Blaser MJ , eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 219.

Pfaff JA, Moore GP. Otolaryngology. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:chap 62.

  • Condition: Malignant (Necrotizing) Otitis Externa (MOE)
  • Journal: European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery
  • Treatment Used: Hyperbaric Oxygen Treatment (HBOT)
  • Number of Patients: 16
  • Published —
This study evaluated the effectiveness of hyperbaric oxygen treatment (HBOT) in the treatment of malignant otitis externa (ear infection; MOE).

There are no recent clinical trials available for this condition. Please check back because new trials are being conducted frequently.