The Investigation of Hypoglycaemia during Childhood

The purpose of this review is to provide a practical basis for the laboratory investigation of hypoglycaemia during childhood. Reference is made to aetiology and treatment but the reader interested in a fuller account of these aspects will find several good existing review articles.lr! The fasting newborn and young child demonstrate a high glucose utilization rate per kilogramme body weight relative to adult requirements.v' In addition, infantile glycogen stores are quickly depleted and the young child's comparatively small muscle mass provides only a limited supply of gluconeogenic precursors. These conditions make the infant particularly vulnerable to developing hypoglycaemia from various causes and, consequently, hypoglycaemia in childhood is relatively common. In the older child the frequency for admission to hospital with hypoglycaemia is approximately one in 500 hospital admissions. The incidence in the well grown term neonate is approximately one in 200 live births and although it is difficult to assess accurately, hypoglycaemia is even more common in the small for gestational age newborn. In order to avoid the long-term neurological damage which may occur when the developing brain is deprived of glucose for even short periods, the clinician and the laboratory need to have agreed, in advance, a clearly defined protocol to deal effectively with these patients.