Decreased Ketogenesis Due to Deficiency of Hepatic Carnitine Acyl Transferase

To the Editor: In 1970 Engel reported in the Journal a disorder of the skeletal muscle without fasting hyperketonemia and with a normal increase in ketone bodies after oral medium-chain triglycerides.¹ He suggested a possible defect in the use of long-chain fatty acids. Usually, fasting is associated with hyperketonemia except in hyperinsulinemic states. Hyperketonemia results from the release of long-chain fatty acids from adipose tissue and their intrahepatic channeling toward mitochondrial oxidation and ketogenesis. The transfer of long-chain fatty acids to the mitochondria for oxidation and ketone-body formation is controlled by acyl carnitine transferase, whereas medium and short-chain fatty acids. . .