Treatment:

The main treatment is with corticosteroid medications. When muscle strength improves, usually in 4 to 6 weeks, the medication is slowly tapered off. Maintenance therapy with prednisone may be continued indefinitely. In people who fail to respond to corticosteroids, medications to suppress the immune system, such as methotrexate and azathioprine, may be used.

Intravenous gamma globulin has been tried, with mixed results. It is too soon to know what role biologic drugs may play in treating this condition.

If the condition is associated with a tumor, it may improve if the tumor is removed.

Expectations (prognosis):

Response to treatment varies, and it depends on whether there are complications. The 5-year mortality can be as high as 20%.

Many patients, especially children, go into remission (a period when no symptoms are present) and recover. For most other people, immunosuppressant drugs can control the disease.

In adults, death may result from:

• Malnutrition
• Pneumonia
• Respiratory failure
• Severe, long-term muscle weakness

The major causes of death are cancer (malignancy) and lung disease.

Complications:

• Calcium deposits in the affected muscles, especially in children with the disease
• Cancer
• Heart disease, lung disease, or abdominal complications

Calling your health care provider:

Call your health care provider if you have symptoms of this disorder. Seek emergency treatment if you have shortness of breath and difficulty swallowing.