Localized nodular myositis.
Two patients presenting with painful, localized swelling in a single muscle are described. Biopsies of involved areas showed inflammatory changes characteristic of polymyositis, but serum levels of muscle-derived enzymes were consistently normal. Both patients later developed evidence of mild diffuse myositis. A review of 4 similar cases in the literature suggests that localized nodular myositis is a heterogeneous condition, in which vascular inflammation may be a prominent feature, with frequent evolution into a generalized myopathy.
D000328:Adult; D001132:Arm; D005260:Female; D006801:Humans; D007866:Leg; D009132:Muscles / Q000503:physiopathology; D009220:Myositis / Q000503:physiopathology*