ABSTRACT
A boy had neonatal seizure, lethargy, and metabolic acidosis at presentation. He recovered completely, but the recurrence of a similar episode with associated cardiomyopathy and dicarboxylic aciduria at 10 months of age led to the recognition of a fatty acid oxidation defect. A diagnosis of very long chain acyl-coenzyme A dehydrogenase deficiency was later made by enzyme assay in culture fibroblasts from this child, as well as in cultured amniotic cells from a sibling fetus. This prenatal diagnosis forestalled neonatal injury by close clinical and metabolic monitoring of the second infant. Early diagnosis and management should potentially improve the generally poor prognosis for patients with very long chain acyl-coenzyme A dehydrogenase deficiency.