Dermatomyositis.

Dermatomyositis is one of the idiopathic inflammatory myopathies. It is characterized clinically by progressive symmetrical proximal muscle weakness and a characteristic rash. There are patients with rash who have little or no muscle disease. Although the process primarily attacks the skin and the muscles, it is a systemic disease with frequent manifestations in the gastrointestinal tract and pulmonary system. Dermatomyositis has been linked to internal malignancy in somewhere between 15% and 25%. Therapy for the muscle disease includes systemic corticosteroids with or without an immunosuppressive agent. Therapy of the skin disease begins with photoprotection and topical corticosteroids, but also includes the use of antimalarial agents and immunomodulatory therapies.