title: Ultrastructure of skeletal muscle in rheumatoid myositis.
abstract: Muscle biopsies from 8 cases of rheumatoid myositis (5 females and 3 males) were studied by electron microscopy. All muscle fibers studied showed either necrosis or atrophy, the latter varying from slight to severe. Mononuclear cell infiltration was present in all cases, with 4 types of cells observed (lymphocytes, plasma cells, macrophages and mast cells). The capillary endothelium showed proliferation of organelles, occlusion of lumina, and thickening of the basement membrane. The pathogenesis of muscle damage in rheumatoid myositis is discussed.
authors.affiliation: Center of Electron Microscopy, Sciences Faculty, Caracas University Hospital, Venezuela.
authors.forename: H J
authors.initials: HJ
authors.lastname: Finol
authors.forename: B
authors.initials: B
authors.lastname: Müller
authors.forename: I
authors.initials: I
authors.lastname: Montes de Oca
authors.forename: A
authors.initials: A
authors.lastname: Márquez
mesh_terms: D001172:Arthritis, Rheumatoid / Q000150:complications*; D001284:Atrophy; D001485:Basement Membrane / Q000648:ultrastructure; D002196:Capillaries / Q000648:ultrastructure; D005260:Female; D006801:Humans; D008297:Male; D008854:Microscopy, Electron; D009132:Muscles / Q000098:blood supply / Q000648:ultrastructure*; D009210:Myofibrils / Q000648:ultrastructure; D009220:Myositis / Q000209:etiology / Q000473:pathology*; D009336:Necrosis; D012518:Sarcomeres / Q000648:ultrastructure