Glycemic response to 24-hour fast in normal children and children with ketotic hypoglycemia: II. Hormonal and metabolic changes

Metabolic and hormonal changes induced by a 24-hour fast were studied in six children with a recent history of ketotic hypoglycemia and in six control children of comparable ages. Mean blood sugar level dropped more in KH children (80-33 mg/dl) than in control subjects (86-55 mg/dl). Glycemia and plasma insulin responses to intramuscular glucagon (0.03 mg/kg) were similar in each group before fast. After fast, they were low or suppressed in KH children, still present in the controls. Plasma growth hormone and free fatty acid levels before and after fast were identical in each group. At the end of the fast, a significant (p≤0.01) correlation was demonstrated between glycemia and plasma cortisol values in children of the two groups. Serum alanine decreased significantly (p≤0.01) in KH and control children, the alanine level at the end of the fast being correlated to blood sugar value. Concentrations of serum branched-chain amino acids increased significantly (p≤0.02) during fast in KH children, but not in controls. Similar biologic data were obtained in an additional KH patient studied at the time of a spontaneous hypoglycemic seizure. It may be concluded that the inability to sustain normal concentrations of blood sugar during fast in children could be related to deficient neoglycogeneis; this feature appears to be variable from one child to another and is more marked in KH children.