[Idiopathic inflammatory myopathy. Analysis of 31 patients]

A series of 31 patients suffering idiopathic inflammatory myopathy (IIM); we describe the extramuscular manifestations, specially pulmonary, the association to neoplasia, the histopathological characteristics, and their response to treatment. Fourty three percent of IIM patients presented a pulmonary involvement, 9% presented an associated neoplasia. The histopathological study allowed us to clearly differentiate dermatomyositis and polymyositis within IIM. 65% of patients initially responded to glucocorticoids and the most usefull therapeutic alternatives were azatioprine and cyclosporin-A.