Differential diagnosis of fatal and benign cytochrome c oxidase-deficient myopathies of infancy: an immunohistochemical approach

Neurology. 1991 Feb;41(2 ( Pt 1)):300-5. doi: 10.1212/wnl.41.2_part_1.300.

Abstract

To differentiate the 2 major myopathies of infancy due to cytochrome c oxidase (COX) deficiency, we studied muscle biopsies from 4 patients with fatal myopathy and 4 with benign myopathy using biochemical, histochemical, and immunohistochemical techniques. Immunohistochemistry with antibodies directed against individual subunits of COX differentiated the 2 phenotypes: the fatal infantile myopathy was characterized by absence of the nuclear DNA (nDNA)-encoded subunit VIIa,b of COX, while in the benign myopathy both VIIa,b and the mitochondrial DNA (mtDNA)-encoded subunit II were absent. Early differential diagnosis between fatal and benign COX-deficient myopathies is of critical importance for prognosis and management of these infants, because the benign form is initially life-threatening but ultimately reversible.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Biopsy
  • Cytochrome-c Oxidase Deficiency*
  • Diagnosis, Differential
  • Electron Transport Complex IV / metabolism
  • Histocytochemistry
  • Humans
  • Immunohistochemistry / methods
  • Infant, Newborn
  • Muscular Diseases / enzymology*
  • Muscular Diseases / mortality
  • Muscular Diseases / pathology

Substances

  • Electron Transport Complex IV