[Dermatomyositis: assessment and follow-up of 20 patients]

Dermatomyositis is an idiopathic inflammatory myopathy that mainly affects the skin and skeletal muscle. An estimated 15% to 25% of patients have underlying tumors and some forms are exclusively cutaneous. The factors that predict disease course and prognosis in these patients have not been clearly identified. Here we report our experience through the description and analysis of a series of patients.

This was a retrospective study of 20 patients with a diagnosis of dermatomyositis undergoing follow-up in the Department of Dermatology at Hospital General Universitario Gregorio Marañón in Madrid, Spain between February 2007 and February 2010. Clinical and histopathological characteristics were assessed alongside the results of laboratory tests and the treatments used.

Nineteen of the 20 patients included in the study were women. The mean age was 61 years (median, 60 years). We identified 11 patients with classic, 3 with amyopathic, 2 with paraneoplastic, 1 with drug-associated, and 1 with juvenile dermatomyositis, and 2 patients had dermatomyositis associated with connective tissue disease. Heliotrope erythema, Gottron papules, and periungual erythema were the most frequent skin lesions. Cutaneous necrosis was present in 2 patients with paraneoplastic dermatomyositis. None of the patients had myositis-specific antibodies. Initial treatment was with systemic corticosteroids in 85% of cases. Eighty percent of patients required 2 or more drugs to achieve disease control.

Dermatomyositis is a potentially serious disease. Dermatologists can facilitate diagnosis and contribute to the early detection of associated tumors and systemic complications. In most patients, the disease has a good prognosis, although extended periods of treatment may be required. Complications occur most commonly in patients with associated tumors or cardiopulmonary disease.