Continuous glucose monitoring reveals severe and persistent postprandial reactive hypoglycemia in a nasogastric tube-fed infant

Abstract Background Reactive postprandial hypoglycemia, or dumping syndrome, is commonly associated with gastric surgeries or gastrostomy tube feeding but has not been previously reported in pediatric patients receiving nasogastric (NG) tube feeds. Methods We describe a 14-month-old girl with Trisomy 21 and congenital heart disease who experienced recurrent hypoglycemia while on NG tube feeds. Evaluation included continuous glucose monitoring (CGM), diagnostic fasting, and a mixed meal tolerance test. Results CGM revealed postprandial hyperglycemia followed by hypoglycemia. A mixed meal test confirmed inappropriate insulin secretion in the postprandial phase. Initiation of acarbose therapy led to immediate and sustained resolution of hypoglycemia without side effects. Conclusion This case highlights a previously unreported association between NG tube feeding and dumping syndrome in pediatric patients. It underscores the value of CGM in diagnosing complex causes of hypoglycemia and supports the effectiveness of acarbose in managing postprandial hyperinsulinemic hypoglycemia in the pediatric population.