Recurrent acute encephalopathy due to fatty acid metabolic defect--report of two cases.

An increasing number of reports indicate that patients with some inherited metabolic diseases may have symptoms resembling those of Reye's syndrome. We describe 2 patients who developed Reye-like syndrome at the age of 7 months respectively. Conscious disturbance, hepatomegaly, impaired liver function, hyperammonemia, and nonketotic hypoglycemia were noted during acute episode. Blood lactate level was normal in both cases. Liver and muscle biopsy of both patients showed macrovesicular fatty change. Increased density of matrix in hepatocyte mitochondria was noted in patient 1. Stacking of cristae was shown in patient 2. The first patient had another episode of hyperammonemia at 2 years of age. The second patient was admitted three more times due to recurrent vomiting and conscious change at the age of 7 months, 10 months and 13 months respectively. Fatty acid metabolic defect should be considered in children or infants with recurrent Reye-like syndrome.