A mitochondrial encephalomyopathy: the first case with an established defect at the level of coenzyme Q

Eur J Pediatr. 1986 Feb;144(5):441-4. doi: 10.1007/BF00441735.


A patient is presented who had therapy-resistant epileptic seizures from the 7th day of life. Examination at the age of 17 months revealed a mentally retarded boy with epileptic seizures, generalised myoclonic contractions, and abnormal ocular movements. A cerebral CT scan showed central and cortical atrophy. Lactate levels in serum, cerebrospinal fluid and urine were elevated, the pyruvate level was raised in serum. A quadriceps muscle biopsy revealed aspecific morphologic signs of a myopathy. Biochemical analysis showed decreased substrate oxidation rates in the mitochondria associated with low rates of ATP production. Total and free carnitine levels were decreased. Investigation of the respiratory chain revealed a defect in the proximal part of respiratory chain involving the region of coenzyme Q. Based on clinical and chemical data it is likely that the patient is suffering from a multi-system disorder.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acidosis / complications
  • Adenosine Triphosphate / metabolism
  • Brain Diseases / enzymology*
  • Epilepsy / complications
  • Humans
  • Infant
  • Intellectual Disability / complications
  • Lactates / metabolism
  • Male
  • Mitochondria, Muscle / ultrastructure*
  • Muscle Spasticity / complications
  • Muscle Spasticity / enzymology*
  • Myoclonus / complications
  • NAD / metabolism
  • Nystagmus, Pathologic / complications
  • Oxidation-Reduction
  • Pyruvates / metabolism
  • Ubiquinone / metabolism*


  • Lactates
  • Pyruvates
  • NAD
  • Ubiquinone
  • Adenosine Triphosphate