Hyperammonaemia and lactic acidosis in a patient with pyruvate dehydrogenase deficiency

A patient who presented in the newborn period with severe lactic acidosis and hyperammonaemia has been shown to have a specific defect in the pyruvate dehydrogenase complex. The secondary inhibition of ureagenesis in this patient appears to be due to a functional deficiency of carbamyl phosphate synthetase.