Medium-chain acyl-CoA dehydrogenase deficiency.

Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is the most frequently diagnosed defect in fatty acid metabolism and is one of the most common inborn errors of metabolism. Diagnosis may be difficult, since the disorder may present as hypoglycemia, sudden infant death syndrome or a Reye's syndrome-like illness. Because of the abrupt clinical deterioration seen with MCAD deficiency, as well as its treatable nature and its genetic implications, this disorder presents a significant challenge for family physicians.