Myringitis, Infectious

Acute infectious myringitis is characterized by inflammation, hemorrhage, and effusion of fluid into the tissue at the end of the external ear canal and the tympanic membrane. This self-limiting disorder (resolving spontaneously with­in 3 days to 2 weeks) often follows acute otitis media or upper respiratory tract infection and frequently occurs epidemically in children.

Chronic granular myringitis, a rare inflammation of the squamous layer of the tympanic membrane, causes gradual hearing loss. Without specific treatment, this condition can lead to stenosis of the ear canal, as granulation extends from the tympanic membrane to the external ear.

Causes

Infectious myringitis is infection of the eardrum by a virus or bacteria.

Myringitis is caused by a variety of viruses and bacteria; the bacteria Mycoplasma is a common cause. The eardrum becomes inflamed, and small, fluid-filled blisters (vesicles) form on its surface. Blisters may also be present in otitis media; however, in myringitis, there is no pus or fluid in the middle ear.

Pain begins suddenly and lasts for 24 to 48 hours. There may be some hearing loss.

Signs and symptoms

The most significant symptom in infectious myringitis is ear pain. Because of infection of the eardrum, there may also be fever and hearing loss. In situations where blisters form on the eardrum and then rupture, there may be bloody and infected-looking material draining from the ear canal. If the myringitis is a result of an infection in the ear canal, there is often significant tenderness around the opening to the ear canal and infected draining material. On examination in a pure primary infectious myringitis, the tympanic membrane is often intensely red with increased prominence of the small blood vessels that perfuse the tympanic membrane. There may be inflammation of the lining of the middle ear. If it is a result of an acute otitis media, there may be infected material or fluid behind the eardrum. If the myringitis is from an external canal infection, then intense swelling and tenderness will be present along with purulent visible debris in the external canal. Chronic myringitis usually has a granular, red tissue on the drum surface covered by infected material.

Diagnosis

In acute infectious myringitis, the diagnosis is based on a physical examination showing characteristic blebs and on a typical patient history. Culture and sensitivity testing of exudate identifies secondary infection. In chronic granular myringitis, physical examination may reveal granulation extending from the tympanic membrane to the external ear.

Treatment

Hospitalization usually isn't required for acute infectious myringitis. Treatment consists of measures to relieve pain. Analgesics, such as aspirin or acetaminophen, and application of heat to the external ear are usually sufficient, but severe pain may necessitate the use of codeine.

Systemic or topical antibiotics prevent or treat secondary infection. Incision of the blebs and evacuation of serum and blood may relieve pressure and help drain exudate, but these measures don't speed recovery.

Treatment of chronic granular myringitis consists of systemic antibiotics or local anti-inflammatory antibiotic combination eardrops, and surgical excision and cautery. If stenosis is present, surgical reconstruction is necessary.

Prevention

Certainly measures taken to reduce the spread of viral illness would be helpful, such as avoiding ill individuals, daycare environments, crowded living conditions, and hand washing. In children suffering from acute otitis media, the pneumonia vaccine (pneumovax) and flu vaccination may help prevent the acute otitis media. Preventing the external canal infection largely depends upon keeping the ear canal dry.