title: Inflammatory and toxic myopathies.
abstract: The major advances in the immunopathogenesis and treatment of inflammatory myopathies, and the main criteria that distinguish polymyositis (PM) from dermatomyositis (DM) or inclusion-body myositis (IBM) are presented. The origin and implications of the amyloid and ubiquitin deposits found within the vacuolated fibers of patients with IBM are considered. The pathogenesis of human immunodeficiency virus (HIV) and human T-cell lymphotrophic virus (HTLV)-I-associated PM is presented, and the role of retroviruses in triggering PM, even in the absence of detectable viral genome within the muscle fibers, is discussed. In addition, three toxic myopathies with distinct morphologic, biochemical, or molecular characteristics, caused by zidovudine [azidothymidine (AZT) myopathy], the cholesterol-lowering-agent myopathy (CLAM), and the combination of blocking agents with corticosteroids are presented.
authors.affiliation: Neuromuscular Diseases Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland.
authors.forename: M C
authors.initials: MC
authors.lastname: Dalakas
mesh_terms: D000305:Adrenal Cortex Hormones / Q000009:adverse effects; D001706:Biopsy; D003882:Dermatomyositis / Q000139:chemically induced / Q000209:etiology* / Q000473:pathology; D003937:Diagnosis, Differential; D006801:Humans; D000960:Hypolipidemic Agents / Q000009:adverse effects; D002479:Inclusion Bodies / Q000648:ultrastructure*; D009132:Muscles / Q000473:pathology; D009220:Myositis / Q000139:chemically induced / Q000209:etiology* / Q000473:pathology; D010197:Pancuronium / Q000009:adverse effects; D017285:Polymyositis / Q000139:chemically induced / Q000209:etiology* / Q000473:pathology; D015215:Zidovudine / Q000009:adverse effects
chemical_list: D000305:Adrenal Cortex Hormones; D000960:Hypolipidemic Agents; D015215:Zidovudine; D010197:Pancuronium