Hypoglycemia in the neonate.

Hypoglycemic episodes occurring during the newborn period are often due to transient immaturity of glucoregulatory pathways. Normal feeding is generally the only measure required to treat such episodes. After the first few hours of life, however, hyperinsulinism (HI) is the most common cause of neonatal hypoglycemia. HI may persist for the first weeks/months of life and then remit spontaneously, particularly in low birth weight neonates and those exposed to perinatal stresses; hypoglycemia in such infants can nearly always be medically controlled using diazoxide. There are also several forms of congenital hyperinsulinism presenting with hypoglycemia in neonates that does not remit. Depending on the type of genetic mutation, hypoglycemia in these infants with congenital hyperinsulinism may be controlled medically or may require surgery. The extent of surgery required in infants with ATP-dependent potassium channel mutations unresponsive to diazoxide is dependent upon histological subtype: focal vs. diffuse disease. Disease-specific diagnoses and treatments are therefore essential for effective management of the various forms of neonatal hyperinsulinism.