Effects of neonatal hypoglycaemia on the nervous system: a pathological study.

Irreversible pathological changes in the central nervous system due to prolonged hypoglycaemia have been described many times in adults (see Lawrence, Meyer, and Nevin, 1942). It is less well known that hypoglycaemia can occur in the neonatal period and that it may be a cause of brain damage at that time. In full-term and premature babies the normal blood glucose concentration during the first few days of extrauterine life is in the range of 30 to 60 mg./100 ml.; blood glucose levels of less than 20 mg./100 ml. are regarded as abnormal. The first account of infants with abnormal clinical signs attributable to hypoglycaemia was probably that of Hartmann and Jaudon (1937). The importance of the condition was not appreciated until 1959 when Comblath, Odell, and Levin described eight newborn babies with symptoms due to severe hypoglycaemia, two ofwhom became spastic and mentally retarded. The eight infants were underweight for their gestational age and had been born to nondiabetic women. Further clinical reports have confirmed that prolonged hypoglycaemia in the neonatal period may lead to death or to survival with mental deficiency and cerebral palsy unless adequate treatment is given (Brown and Wallis, 1963; Comblath, Wybregt, Baens, and Klein, 1964; Haworth and McRae, 1965). It has also been established that the infants most liable to develop serious hypoglycaemia are those born with poor liver carbohydrate stores, that is, the very premature and those that are underweight because of intrauterine malnutrition (Shelley and Neligan, 1966). To our knowledge there have been no accounts of the pathological findings in acute or chronic brain damage due to neonatal hypoglycaemia, apart from a preliminary report of our cases 1 and 2 (Anderson, Milner, and Strich, 1966). We now present the clinical histories and pathological findings in six patients, three in whom hypoglycaemia was regarded as the major cause of death and three who died of other causes after the hypoglycaemia had been successfully treated.