Feeding practices and nutritional management of infants with transient and congenital hyperinsulinism: A tertiary single‐center retrospective study

BACKGROUND AND AIMS: Hyperinsulinism (HI) is the most common cause of persistent neonatal hypoglycemia and requires careful nutritional management to maintain glycemic stability. Infants with transient hyperinsulinism (THI) often recover within months, whereas congenital hyperinsulinism (CHI) frequently requires prolonged medical and nutritional support. This study aimed to compare feeding practices and nutritional management of infants with THI and CHI. METHODS: This single-center retrospective study included infants diagnosed with HI under 12 months of age between January 2020 and January 2023. Infants were classified as THI if diazoxide was discontinued within six months and as CHI if treatment continued beyond six months. Data was collected at baseline and at one, three, and six months post-diagnosis, with an additional one-year follow-up for the CHI group. RESULTS: Ninety-six infants were included (THI n = 74, CHI n = 22). 78% of the THI group and all infants with CHI required support from intravenous dextrose and/or parenteral nutrition at diagnosis. The CHI group demonstrated greater use of glucose polymers, high-energy and hydrolyzed formulas by six months. By six months, 95% of the THI group were exclusively orally fed compared with 59% in the CHI group. Breastfeeding rates were low in both groups, declined over time and did not recover after medication was stopped. CONCLUSIONS: Infants with CHI require more prolonged and complex nutritional management, characterized by sustained reliance on tube feeding and higher carbohydrate feeds. Early optimization of nutritional intake and clearer strategies to support breastfeeding are areas for improving clinical management and feeding outcomes of infants with THI and CHI.