Symptomatic leucine sensitivity in a mother and daughter

Abstract

A mother and daughter with symptomatic leucine sensitive hypoglycemia are described. Tolerance tests were performed with oral glucose, intravenous sodium tolbutamide, oral leucine and intravenous glucagon. The mother developed asymptomatic hypoglycemia after 72 hours of fasting and symptomatic hypoglycemia after leucine ingestion. The daughter had frequent symptomatic fasting hypoglycemia and distinct sensitivity to oral leucine. Diets low in leucine (500–900 mg./24 hours) and totally deficient in leucine significantly improved the daughter's post prandial hypoglycemia but not her fasting hypoglycemia.