Hypoglycaemia and Russell-Silver syndrome.

AIM: To determine both the incidence and aetiology of chronic hypoglycaemia in symptomatic children with Russell-Silver syndrome (RSS) during the first four years of life.

STUDY

DESIGN

Twenty-four children with RSS under the age of 4 years, who had either clinical symptoms of hypoglycaemia or previous evidence of biochemically documented hypoglycaemia, were admitted to hospital for 48 hours to perform a 24-h cortisol/glucose profile and a diagnostic fast in those who did not develop spontaneous hypoglycaemia. A dietary assessment was also performed. Glucose profile was assessed in 20 children and cortisol profile in 16; combined glucose and cortisol profile in 15 children. Eight children had a diagnostic fast. Mean chronological age at time of assessment was 2.2 +/- 0.8 years (range 1.1-3.9 years).

RESULTS

Ten of 24 children had previously been documented as having hypoglycaemia. Seven of 12 patients were growth hormone (GH) insufficient after a glucagon test. Their feeding pattern was described as 'poor and picky eaters' in all, seven requiring nasogastric tube feeding. The mean spontaneous energy intake (n = 8) was 56 +/- 19.6 kcal/kg/day (range 38-90). Nocturnal sweating was the commonest symptom (23.96%), followed by irritability (11.46%), tantrums (7.29%), pallor and shakiness (3.13%). The glucose profile in seven children showed hypoglycaemia but only four were symptomatic. None of the children was cortisol deficient. The mean period of fasting was 11.8 +/- 4 hours (range 3-18 h). No metabolic/hormonal abnormality, with the exception of GH insufficiency, was detected at the time of hypoglycaemia.

CONCLUSION

Children with RSS are prone to develop spontaneous hypoglycaemia especially if they are not fed both frequently and regularly. The most likely explanation is accelerated starvation and/or GH insufficiency. We suggest guidelines to minimise hypoglycaemia in these children.