Myopathy with MTCYB mutation mimicking Multiple Acyl-CoA Dehydrogenase Deficiency

Rev Neurol (Paris). 2018 Dec;174(10):731-735. doi: 10.1016/j.neurol.2018.03.014. Epub 2018 Oct 11.

Abstract

We describe two patients with mitochondrial DNA mutations in the gene encoding cytochrome b (m.15579A>G, p.Tyr278Cys and m.15045G>A p.Arg100Gln), which presented as a pure myopathic form (exercise intolerance), with an onset in childhood. Diagnosis was delayed, because acylcarnitine profile showed an increase in medium and long-chain acylcarnitines, suggestive of multiple acyl-CoA dehydrogenase deficiency, riboflavin transporter deficiency or FAD metabolism disorder. Implication of cytochrome b in fatty acid oxidation, and physiopathology of the mutations are discussed.

Keywords: Cytochrome b; Exercise intolerance; MADD; Mitochondrial disease; Multiple acyl-CoA dehydrogenase deficiency; Myopathy.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Aged
  • Cytochromes b / genetics*
  • DNA, Mitochondrial / genetics
  • Diagnosis, Differential
  • Exercise Tolerance / genetics
  • Humans
  • Male
  • Multiple Acyl Coenzyme A Dehydrogenase Deficiency / diagnosis*
  • Multiple Acyl Coenzyme A Dehydrogenase Deficiency / genetics
  • Muscular Diseases / diagnosis*
  • Muscular Diseases / genetics*
  • Mutation, Missense*

Substances

  • DNA, Mitochondrial
  • Cytochromes b