Diazoxide treatment for persistent hypoglycemia in a small for gestational age preterm infant with adequate low insulin levels

Small for gestational age (SGA) newborn infants can have prolonged hypoglycemia due to diminished glycogen stores, diminished alternative energy substrates, or hyperinsulinism. Recurrent episodes of hypoglycemia are strongly correlated with persistent neuro-developmental and physical growth deficits. Treatment includes glucose supplements or medications affecting insulin secretion, gluconeogenesis, or glycogenolysis. Diazoxide suppresses insulin secretion by acting as an ATP-sensitive potassium channel agonist to prevent membrane depolarization, calcium influx, and insulin secretion. Therefore, it is used in persistent hypoglycemia of neonates associated with hyperinsulinism. We report a case of a female SGA preterm infant who had persistent hypoglycemia (> 2 weeks of age) with low adequate serum insulin levels and no other clear biochemical evidence of hyperinsulinism or other abnormalities. As a result of an inability to control her glucose levels without high intravenous levels of glucose and continuous glucagon infusion, she was treated successfully with diazoxide, which was discontinued when the infant reached 5 kg. No side effects were noted. In rare cases of persistent hypoglycemia, and a need for high glucose infusion rate but with adequate low insulin levels even without biochemical evidence supportive of hyperinsulinism, diazoxide treatment can be offered with close monitoring of glucose levels and possible side effects. The exact mechanism is not clear and deserves further evaluation.