title: Cortisol and growth hormone responses to spontaneous hypoglycaemia in infants and children.
abstract: OBJECTIVE
  To evaluate responses of cortisol and growth hormone (GH) to spontaneous hypoglycaemia in infants and children.
  
  
  METHODS
  Retrospective review of laboratory and clinical data in paediatric patients investigated for suspected hypoglycaemia over a five year period. Thirty patients (16 aged <3 months) had hypoglycaemia confirmed by laboratory analysis (glucose <2.5 mmol/l) and were compared with 26 patients (11 aged <3 months) with glucose > or =2.5 mmol/l.
  
  
  RESULTS
  The commonest causes of hypoglycaemia were transient hyperinsulinism in infants <3 months and intercurrent infection in those >6 months of age. In both hypo- and non-hypoglycaemic patients, cortisol was positively (r(s) +0.66 and +0.68) and GH inversely (r(s) -0.65 and -0.75) correlated with age. Hypo- and non-hypoglycaemic infants <3 months had median cortisol concentrations of 205 and 116 nmol/l respectively compared with 1370 and 736 nmol/l in hypo- and non-hypoglycaemic children >6 months. Conversely, median GH was 46.5 and 51.2 mU/l in hypo- and non-hypoglycaemic infants compared with 14.3 and 12.1 mU/l in older hypo- and non-hypoglycaemic patients. Older non-hypoglycaemic patients with glucose levels below the glycaemic thresholds established for cortisol and GH secretion in adults had higher cortisol and GH concentrations than patients whose glucose levels exceeded these thresholds.
  
  
  CONCLUSIONS
  Cortisol and GH responses to spontaneous hypoglycaemia in children are highly age dependent. Young infants mount a poor cortisol response compared with older infants and children. Children older than 6 months may have glycaemic thresholds for cortisol and GH similar to those established for adults.
authors.affiliation: Department of Paediatric Biochemistry, Royal Hospital for Sick Children, Edinburgh, UK. patricia.crofton@luht.scot.nhs.uk
authors.forename: P M
authors.initials: PM
authors.lastname: Crofton
authors.forename: P C
authors.initials: PC
authors.lastname: Midgley
mesh_terms: D001786:Blood Glucose / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D013006:Growth Hormone / Q000378:metabolism*; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism*; D007003:Hypoglycemia / Q000378:metabolism*; D007223:Infant; D007231:Infant, Newborn; D012189:Retrospective Studies
chemical_list: D001786:Blood Glucose; D013006:Growth Hormone; D006854:Hydrocortisone