Adult-onset polymyositis-dermatomyositis: description of 25 patients with emphasis on treatment.

A retrospective study of 25 patients with polymyositis-dermatomyositis (PM-DM) is analyzed with special attention to the effects of therapy and follow-up. All patients (100%) complained of muscle weakness and 68% of these demonstrated typical skin changes of DM. All patients, except 2, received corticosteroids at the onset of the disease, 23 were treated with azathioprine, 7 received cyclophosphamide, 4 methotrexate, and 1 had total body irradiation. Among the patients adequately treated with azathioprine, 75% had a good response, but 5 patients did not improve. Cyclophosphamide was used subsequently in 2, with a satisfactory response in 1. Another patient had a striking response to oral methotrexate, and total body irradiation helped to improve another patient. Although high dose corticosteroids were the preferred starting medication for the treatment of PM-DM, it is important to detect those patients who do not respond adequately and/or develop side effects. In these circumstances, the prompt use of immunosuppressive agents appears justified.