Inherited defects of mitochondrial fatty acid oxidation: clinical and biochemical findings

ABSTRACT

Fatty acids are a major source of energy in humans. They are predominantly metabolized in mitochondria and several inborn errors of mitochondrial fatty acid oxidation have recently been described. These inborn errors are probably more common than presently considered and the incidence of one of the defects, medium-chain acyl-CoA dehydrogenase deficiency, may be as high as 1 in 10 000. Defects of mitochondrial fatty acid oxidation are the underlying defect in 5-10% of infants with the sudden infant death ['cot death'] syndrome. These defects may also present as other distressing illnesses such as Reye's syndrome, recurrent hypoglycaemia, encephalopathy or severe muscle weakness. In some cases knowledge of the cause of the defect will lead to rational and successful treatment with dietary and vitamin supplementation. This review describes the inborn errors of mitochondrial fatty acid oxidation, stressing the clinical presentation and the recent progress in the study of these disorders