title: Mitochondrial abnormalities in dermatomyositis: characteristic pattern of neuropathology.
abstract: The objective of the work described in this paper was to evaluate mitochondrial abnormalities in perifascicular atrophic fibers in muscle biopsies from patients with dermatomyositis (DM). We localized cytochrome c oxidase (COX) and succinate dehydrogenase (SDH) histochemically in muscle biopsies of 12 patients with DM, and 12 control patients with neurogenic atrophy. These two histochemical techniques were also combined on single tissue sections in order to accentuate any COX-negative fibers. Eleven out of 12 patients (91.6%) with DM showed histochemical evidence of mitochondrial dysfunction in perifascicular distribution. Similar abnormalities in histochemical staining were not seen in comparably sized myofibers that were atrophic due to denervation. It is concluded that abnormal SDH and COX histochemical activities in atrophic perifascicular fibers are characteristic of dermatomyositis. These abnormal staining characteristics could not be accounted for solely by myofiber atrophy, or by generalized abnormalities in histochemical staining.
authors.affiliation: Department of Neurology, Emory University School of Medicine, Atlanta, Georgia, USA. malhatou44@hotmail.com
authors.forename: Mohammed I
authors.initials: MI
authors.lastname: Alhatou
authors.forename: John T
authors.initials: JT
authors.lastname: Sladky
authors.forename: Omar
authors.initials: O
authors.lastname: Bagasra
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Glass
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D003882:Dermatomyositis / Q000201:enzymology* / Q000473:pathology*; D003576:Electron Transport Complex IV / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000201:enzymology* / Q000473:pathology*; D018482:Muscle, Skeletal / Q000166:cytology / Q000201:enzymology / Q000473:pathology; D013385:Succinate Dehydrogenase / Q000032:analysis
chemical_list: D013385:Succinate Dehydrogenase; D003576:Electron Transport Complex IV