Mitochondrial e1ectron transport chain defect presenting as hypoglycemia

Abstract

A profoundly deaf female infant was found to have hypoglycemia and lactic acidemia after an episode of decreased oral intake and vomiting. Electron transport chain (ETC) enzyme studies revealed a combination defect of complexes I, III, and IV in liver bur not in skeletal muscle. This case highlights the fact that defects of the ETC are clinically highly heterogenous and should be considered with hypoglycemia and lactic acidosis the absence of a glycogen storage disorder. Moreover, ETC defects can occur with a biochemical profile suggestive of a fatty acid oxidation disorder.