[Myopathy associated to human immunodeficiency virus (HIV) infection]

Myopathy associated with HIV infection is rare and generally appears before the manifestations of other symptoms of AIDS. Its first symptoms are proximal weakness and myalgias, together with increased CPK. Electromyographic studies show either a myopathic pattern or the mixed pattern characteristics of inflammatory myopathies. Histologically they can be classified into three groups: 1) cases which present only with necrosis and regeneration of fibers; 2) those which associate to the above findings, inflammatory infiltrates, and 3) cases whose predominant characteristics is the presence of nemaline structures, with or without inflammation. The etiology of the AIDS associated myopathy is unknown, but most factors indicate an autoimmune mechanism in the pathogenesis of the disease.