Malignant otitis externa
Key points
- Malignant otitis externa is a disorder involving inflammation and damage of the bones and cartilage of the base of the skull.
- A doctor will look into your ear for signs of an outer ear infection (otitis externa).
- Malignant otitis externa usually responds to prolonged treatment but may return in the future.
- Go to the emergency room or call the local emergency number (such as 911) if Convulsions, decreased consciousness, severe confusion, or similar symptoms develop.
Alternative names
Osteomyelitis of the skull; Otitis externa - malignant
Definition
Malignant otitis externa is a disorder involving inflammation and damage of the bones and cartilage of the base of the skull. It is caused by the spread of infection from an external ear infection (otitis externa).
- Malignant = harmful and invasive
- otitis = ear infection and inflammation
- externa = outer
Causes, incidence, and risk factors Otitis externa, also called swimmer's ear, is an ear infection that occurs in the outer ear. Malignant otitis externa is an uncommon complication of both acute otitis externa and chronic otitis externa. Diabetics and people whose immune systems are compromised from diseases or medications are particularly susceptible to malignant otitis externa.
The infection of external otitis, often caused by difficult-to-treat bacteria such as Pseudomonas, spreads from the floor of the ear canal to the adjacent tissues and into the bones of the base of the skull. The bones may be damaged or destroyed from the resulting infection and inflammation. The infection may further spread and affect the cranial nerves, the brain, or other parts of the body.
Symptoms
- drainage from the ear
o yellow, yellow-green, pus, foul smelling
o persistent - hearing loss
- ear pain
o may worsen on head movement
o may be located deep within the ear - 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 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 to be performed. The purpose of the culture is to look for bacteria or fungus, usually the bacteria Pseudomonas.
To look for signs of a bone infection adjacent to the ear canal, the following tests may be performed:
- CT scan of the head
- X-rays of the skull
- MRI scan of the head
- Radionuclide scan
Treatment
The goal of treatment is to cure the infection. Treatment is often prolonged, lasting several months, because of the difficulty of treating the bacteria and the difficulties reaching an infection that is within bone tissue.
Written and revised by
Andrey Nailor, M.D.
Our doctors write and review articles for accuracy and keep them up to date.
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