Angelo M. Di George

LEUCINE-INDUCED HYPOGLYCEMIA. III. THE BLOOD GLUCOSE DEPRESSANT ACTION OF LEUCINE IN NORMAL INDIVIDUALS.

The administration of l -leucine to leucine-sensitive children produces profound hypoglycemia. The effect of l -leucine on the blood glucose concentration of normal individuals has been studied. A small but definite effect has been found which suggests that a homeostatic relationship between the amino acid and insulin exists. This relationship is abnormal in the children with leucine-sensitive hypoglycemia.

Treatment Variables and Intellectual Outcome in Children With Classic Phenylketonuria A Single-Center-Based Study

Records of 46 patients with classic phenylketonuria (PKU) were used to determine treatment variables associated with intellectual outcome. Patients comprised three groups: phenylalanine-restricted diet started 1) after 3 months and loss of diet control at a mean age of 7 years, 2) before age 3 months and loss of diet control at a mean age of 5 years, and 3) before age 3 months and through a mean age of 11 years. All underwent IQ testing during the diet; groups 1 and 2 were retested at a mean of six years off the diet. On the diet, groups 2 and 3 had higher IQs than group 1; group 3 IQ was also higher than IQ off diet in groups 1 and 2. After discontinuing the diet, group 2 IQs decreased significantly. Predictors of IQ in group 1 were age at loss of diet control and percentage of phenylalanine concentrations >15 mg/dL; in group 2, mean phenylalanine concentrations and age at loss of diet control. Predictors of changes in group 1 IQs were global degree of dietary control and percentage of phenylalanine concentrations >15 mg/dL; in group 2, phenylalanine concentrations of <3 mg/dL and age at start of diet. Group 1 patients with phenylalanine concentrations <3 mg/dL or >15 mg/dL achieved no IQ gain by continuing the diet after age 7 years. Thus, intellectual prognosis is best for PKU patients who start a phenylalanine-restricted diet early and continue through age 12 years.