Fatty liver, encephalopathy, and sudden unexpected death in early childhood due to medium-chain acyl-coenzyme A dehydrogenase deficiency.

A case of sudden death associated with fatty liver and encephalopathy is described in a 4-year old white boy with medium-chain acyl-coenzyme A dehydrogenase (MCAD) deficiency. The death was caused by hypoglycemia triggered by fasting and vomiting associated with a minor viral infection. The differential diagnosis of the hepatoencephalopathy is discussed in relation to other conditions, especially Reye's syndrome. The forensic pathologist should be familiar with MCAD and other deficiencies of beta-oxidation of fatty acids as a cause of sudden unexpected death in children in order to advise parents in genetic counseling to prevent disability or death of other affected, but still asymptomatic siblings.