Metabolic screening and postnatal glucose homeostasis in the newborn.

Although individual metabolic diseases are relatively uncommon, inherited metabolic diseases collectively represent a more common cause of disease in the neonatal period than is generally appreciated. Newborn screening is among the most successful public health programs today. Every day, newborns considered to be at risk for hypoglycemia are screened. The definition of clinically significant hypoglycemia remains among the most confused and contentious issues in neonatology. There are 2 "competing" methods of defining hypoglycemia that suggest very different levels for management: one based on metabolic-endocrinologic hormones and another that uses outcome data to determine threshold levels of risk.