title: Toxic myopathies: muscle biopsy features.
abstract: Several drugs and toxic substances can cause muscular abnormalities and are frequent causes of acquired myopathies. We present a series of 32 patients, predominance of young adult patients, diagnosed with toxic myopathy. The most common substances inducing myopathy were corticosteroids (56.2%) followed by the propoxyphene, neuroleptics, zidovudine and drug-induced hypokalemia. The investigation showed normal serum creatine kinase levels in 65.4%, myopathic pattern of the needle electromyography in 40% and the more frequent histological diagnosis of the muscle biopsy was type 2 fiber atrophy (59.3%). Clinical features, etiology, course of the disease, serum levels of muscular enzymes, electromyographic features and, especially, muscle biopsy features are discussed.
authors.affiliation: Neuromuscular/Neurology Division, Internal Medicine Department, Hospital de Clínicas, Universidade Federal do Paraná, Rua General Carneiro 181, 80060-900 Curitiba, PR, Brazil.
authors.forename: Rosana Herminia
authors.initials: RH
authors.lastname: Scola
authors.forename: Eduardo Rafael
authors.initials: ER
authors.lastname: Pereira
authors.forename: Paulo José
authors.initials: PJ
authors.lastname: Lorenzoni
authors.forename: Lineu César
authors.initials: LC
authors.lastname: Werneck
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001706:Biopsy; D002648:Child; D003402:Creatine Kinase / Q000097:blood; D004576:Electromyography; D005260:Female; D005634:Fructose-Bisphosphate Aldolase / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D009135:Muscular Diseases / Q000139:chemically induced* / Q000201:enzymology / Q000473:pathology; D012189:Retrospective Studies
chemical_list: D003402:Creatine Kinase; D005634:Fructose-Bisphosphate Aldolase