Endocrine Abstracts

Background: Timely diagnosis and management of neonatal hypoglycaemia is important due to associated short and long-term sequelae including neurodevelopmental delay. Hyperinsulinism should be distinguished from other causes of hypoglycaemia as management and acceptable glycaemic parameters may be different.

Aims: To characterize admissions with hypoglycaemia and assess the use of hypoglycaemia screen to detect hyperinsulinism.

Methods: Retrospective case note review of infants admitted to a tertiary neonatal unit between 1^st January 2011 to 31^st December 2014 with a primary diagnosis of hypoglycaemia.

Results: One hundred and two consecutive cases were reviewed (5.1–8.5% of total annual NICU admissions). Median gestational age=37.4 weeks (range=33.4–42.1), 64% of cases >37 weeks gestation. Median birthweight=2710.5 g (range=1600–4830 g). 88% of cases were classified as ‘infants at risk of hypoglycaemia’ by hospital guidelines. 76% had no history of maternal diabetes, 13% had mothers with gestational diabetes, 7% had mothers with type 1 diabetes and 4% had mothers with type 2 diabetes. 19% had evidence of neonatal sepsis, 27% had a maternal preeclampsia and 100% had an Apgar score >9 at 10 minutes. 83% had no hypoglycaemia screen. Cases with a glucose infusion rate (GIR) >8 mg/kg per min, 63% had no hypoglycaemia screen and >10 mg/kg per min, 53% had no hypoglycaemia screen. Twelve cases (12% of total) had biochemical evidence of hyperinsulinism, with 1/12 having a history of maternal diabetes (Type 2). Comparing those with hyperinsulinism with those with either normal hyposcreen or no screen taken; there was significantly longer duration of IV fluids (140.5hours vs. 59hours, P=0.003) and hospital stay (12.5 days vs 6 days, P=0.003) but no significant difference in birthweight (2425 g vs 2580 g, P=0.76), time to stable glucose (27 hours vs 19 hours, P=0.26) and GIR (10.25 mg/kg per min vs 6.0 mg/kg per min, P=0.12).

Conclusion: Hypoglycaemia is a common reason for admission to the neonatal unit. There were missed opportunities for a hypoglycaemia screen, especially in those with high GIR. Those with hyperinsulinism take longer to discontinue IV fluids and stay longer in hospital.