Familial Reye-like syndrome: a presentation of medium-chain acyl-coenzyme A dehydrogenase deficiency.

A 20-month-old girl with a family history of two siblings who died of an encephalopathy diagnosed as Reye syndrome presented to an emergency room in hypoglycemic coma and was found to have medium-chain acyl-coenzyme A dehydrogenase deficiency. The salient clinical and biochemical features of this newly described inborn error of fatty acid metabolism are described and contrasted to those of classical Reye syndrome. Important clues that should lead the clinician to suspect this disorder, methods of diagnosis, and appropriate acute and long-term therapy are also discussed.