title: Cytochrome c oxidase reaction improves histopathological assessment of zidovudine myopathy.
abstract: Zidovudine can induce a mitochondrial myopathy with ragged-red fibers and partial cytochrome c oxidase deficiency. In an attempt to improve histological assessment of zidovudine myopathy, we evaluated cytochrome c oxidase histochemical reaction in the muscle of 10 patients with biopsy-proven zidovudine myopathy (Group 1), 10 myopathic zidovudine receivers without typical histopathological features of zidovudine myopathy (Group 2), and 10 human immunodeficiency virus (HIV)-infected patients not treated by zidovudine who had an immunohistological profile of HIV-associated myopathy or other neuromuscular disorders (Group 3). Among zidovudine receivers, cytochrome c oxidase deficiency was found in 10 of 10 patients from Group 1 and 7 of 10 from Group 2. No cytochrome c oxidase deficiency was observed in patients not treated by zidovudine. When present, cytochrome c oxidase-negative fibers accounted for 2 to 28% of fibers, and there was no difference for the number of cytochrome c oxidase-negative fibers between Group 1 and Group 2. Most patients with cytochrome c oxidase deficiency that could be evaluated clinically after muscle biopsy improved after withdrawal of zidovudine (5 of 7 in Group 1, 5 of 5 in Group 2). Patients who did not improve had an HIV-associated myopathy concurrently with zidovudine myopathy. We conclude that cytochrome c oxidase reaction may be used as a reliable marker of zidovudine mitochondrial toxicity in HIV-infected patients with muscular symptoms.
authors.affiliation: Department of Pathology (Neuropathology), Hospital Henri Mondor, Créteil, France.
authors.forename: P
authors.initials: P
authors.lastname: Chariot
authors.forename: I
authors.initials: I
authors.lastname: Monnet
authors.forename: R
authors.initials: R
authors.lastname: Gherardi
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy; D000328:Adult; D000368:Aged; D030401:Cytochrome-c Oxidase Deficiency; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017240:Mitochondrial Myopathies / Q000139:chemically induced / Q000201:enzymology* / Q000473:pathology*; D015215:Zidovudine / Q000009:adverse effects* / Q000627:therapeutic use
chemical_list: D015215:Zidovudine