Rheumatology

Dermatomyositis/Polymyositis

What is Dermatomyositis?

Dermatomyositis is an uncommon inflammatory disease that is accompanied by a skin rash and muscle weakness.

Dermatomyositis can affect adults and children. In adults, dermatomyositis occurs from the late 40s to early 60s; in children, it occurs between ages of 5 to 15. Dermatomyositis typically affects more females than males. Younger patients have a better prognosis than adult patients.
 

Who is impacted?

Cause of dermatomyositis remains unknown, but can occur almost at any age, typically middle age. It is more common in the caucasian population and affect twice as more females than males.
 

How is Dermatomyositis diagnosed?

Dermatomyositis is typically diagnosed with one or more of the following tests:
 

• Blood Analysis
• Chest X-ray
• Electromyography
• MRI
• Skin/Muscle biopsy

How is it treated?

Unfortunately, there is no cure for dermatomyositis, but treatment can improve skin, muscle strength, and function. The earlier the treatment for dermatomyositis is started, the more effective it is. Available treatments include medication, physical therapy, and surgery.

Corticosteroid medications, such as prednisone, are the preferred method of treatment in most cases. This class of medication can be applied to skin or taken orally. They reduce the response of your immune system, minimizing the number of inflammation-causing antibodies. For some, especially children, symptoms may resolve completely after a treatment course with corticosteroids. This is called remission. Remission may be long-lasting and at times, even permanent. This class of medication should not be used for a long period of time due to adverse effects.

If corticosteroids alone don’t improve your symptoms, other medications may be prescribed in conjunction or as an alternative to suppress your immune system. Corticosteroid-sparing medications are used to reduce the adverse effects associated with corticosteroids. Medications such as azathioprine and methotrexate may be used if you have a severe case of dermatomyositis or if you have complications associated from corticosteroids.

Intravenous Immunoglobulin (IVIG) is an effective additional therapy for patient with dermatomyositis who fail to respond to conventional therapy or who experience undesirable adverse effects. A number of clinical trials suggests an overall response rate of 80% at about 2 months, with maximal response at 4 months. Most patients requiring ongoing IVIG therapy in combination with conventional treatments given at a lower and better tolerated dose.