Hypoglycémie néonatale

Birth is a crucial period for the neonate, who needs to develop adaptive pathways to regulate glycemia whatever the prandial status, in contrast with in utero continuous placental glucose transfer. The inversion of the glucagon/insulin ratio allows the newborn to mobilize his liver reserves (glycogen) and fat mass. When there is no equilibrium between energetic stores (prematurity, small for gestational age), and tissue consumption (infection, respiratory distress, hypothermia), or when hyperinsulinism blocks adaptive mechanisms (neonates born to a mother with gestational diabetes mellitus, macrosomia), there is a predictable risk for hypoglycemia. These neonates should be identified so that their glycemia is attentively followed up and appropriate treatment given (increase of glucose and gluconeogenic substrates enteral and/or parenteral intakes). Most of the time, hypoglycemia is rapidly controlled and there is no need to explore. On the other hand, if hypoglycemia persists, or occurs in a newborn without any risk factors, or needs a massive amount of glucose to be corrected, it is necessary to look for a metabolic or endocrine etiology such as congenital hyperinsulinism, hypopituitarism, adrenal insufficiency, fatty acid β-oxidation defects, or glycogen storage disease type 1. Blood and urine tests during hypoglycemia can easily determine the diagnosis, leading to specific treatment.