ULTRASTRUCTURE OF SYSTEMIC-SCLEROSIS INFLAMMATORY MYOPATHY

Muscle biopsies from 7 patients with systemic sclerosis (SS) and a slo wly progressive proximal muscular weakness were studied ultrastructura lly. In all cases an inflammatory myopathy was found exhibiting fibre atrophy, occasional fibre necrosis, connective tissue proliferation, f ilamentous bodies, concentric laminated bodies and a mononuclear cell infiltration formed by lymphocytes, macrophages and mast cells. Capill ary abnormalities included alterations of endothelium, thickening and reduplication of basement membrane and the presence of cylindric confr onting cisternae. The different associations between muscle diseases a nd SS are grouped. Our data suggest that SS inflammatory myopathy is a distinct clinical and pathological entity.