Endocrine Abstracts

JOINT1790

Introduction: Hyperinsulinemic hypoglycaemia(HH) is a common cause of persistent hypoglycaemia in neonates. Risk factors for transient HH include small for gestational age(SGA) newborns, perinatal asphyxia, intrauterine infections, preeclampsia, and maternal diabetes. In neonates with HH and SGA, hypoglycaemia frequently has good response to diazoxide despite persisting for several months.

Objective: to review a cohort of patients diagnosed with HH in the neonatal period with a history of SGA.

Patients and Methods: Descriptive and retrospective study conducted at a tertiary hospital.

Inclusion criteria: Newborns with SGA (birth weight or length ≤-2 SD Carrascosa 2010) and HH: glucose <50 mg/dL with detectable insulin and/or C-peptide, and/or low free fatty acids(<1800 µg/dL) and carbohydrate requirements >12 mg/kg/min.

Exclusion criteria: Neonates with infection or syndromic hypoglycemia. Medical records were reviewed. Genetic testing included the ABCC8, AKT2, CACNA1C, FOXA2, GCK, GLUD1, HADH, HK1, HNF1A, HNF4A, INSR, KCNJ11, SLC16A1, UCP2, and PGM1 genes.

Results: Twenty patients met inclusion criteria and none of the exclusion criteria. Thirteen(65%) were male. The mean gestational age was 34. 8±2. 9 weeks, with 14(70%) being preterm. Birth anthropometry(Mean±SD): weight Z-score -1. 9±0. 6 and length Z-score -1. 7±1. The mean age at hypoglycaemia onset was 1. 3±0. 7 days. Biochemical parameters during hypoglycaemia(Mean±SD): glucose 37. 3±11. 6mg/dL, cortisol 16±15. 8µg/dL, insulin 6. 8±8mU/l, and C-peptide 1±0. 8ng/mL. Five patients(33%) had prematurity-related complications. Three(15%) had left ventricular hypertrophy(LVH) on echocardiography, one with a patent foramen ovale(PFO) and one with an intraventricular communication.

Treatment: All patients required initial intravenous glucose and continuous nasogastric feeding, with an average carbohydrate intake of 18. 1±3. 6mg/kg/min. Seventeen(85%) needed additional enteral supplementation with dextrin-maltose with maximum concentration of 5±1. 1%. Fourteen(70%) were treated with diazoxide, with a mean dose of 10±4. 4mg/kg/day. Thirteen patients responded well except for one with partial response. Diazoxide was discontinued after a mean of 5. 1±3 months. Two preterm patients experienced complications from diazoxide: Reopening of the ductus arteriosus with no previous cardiopathy and pulmonary hypertension with previous PFO and LVH. The mean age to treatment (enteral and pharmacological) discontinuation was 5. 2±5. 4 months.

Genetics: NGS was performed in ten patients, with one showing heterozygous VUS variant in UCP2(c. 127-1G>T). The Array CGH and exome sequencing were normal in the two and three patients tested, respectively.

Conclusions: In our cohort of SGA patients, HH resolved in average of five months. Most responded well to diazoxide. Two preterm presented complications. Genetic studies might be not necessary in the first six month of live if there is clinical resolution of hypoglycaemia.