J Pediatr Endocrinol Metab 2017; 30(7): 791–795 Case Report Rade Vukovic*, Tatjana Milenkovic, Maja Djordjevic, Katarina Mitrovic, Sladjana Todorovic, Adrijan Sarajlija and Khalid Hussain Postprandial hyperinsulinemic hypoglycemia in a child as a late complication of esophageal reconstruction DOI 10.1515/jpem-2017-0139 Received April 6, 2017; accepted June 2, 2017; previously published online June 24, 2017 Abstract Background: Postprandial hyperinsulinemic hypoglyce- mia (PHH) is an increasingly recognized complication of gastric bypass surgery in obese adults, distinct from the “dumping syndrome”. Case presentation: Upon birth, primary repair of esopha- geal atresia was performed, and at the age of 14 months definite esophageal reconstruction was performed. At the age of 3 years, recurrent brief episodes of sympto- matic hypoglycemia started. At the age of 5.7 years the girl was admitted to our clinic and investigations indi- cated hyperinsulinemic hypoglycemia. Oral glucose tol- erance test (OGTT) and continuous glucose monitoring results revealed frequent postprandial hypoglycemic events, which were always preceded by early postpran- dial hyperglycemia. It was concluded that the patient had PHH caused by a delayed and hyperinsulinemic response to carbohydrate intake as a result of esophagogastric surgery. Treatment with acarbose was titrated using flash glucose monitoring, which resulted in satisfactory glucose regulation. Conclusions: This is the first described case of a child with PHH following esophageal reconstruction. Keywords: dumping syndrome; esophageal atresia; esophageal reconstruction; postprandial hyperinsuline- mic hypoglycemia; reverse gastric tube. Introduction Postprandial hyperinsulinemic hypoglycemia is an increasingly recognized complication of gastric bypass surgery in the obese adults, within the “post-bariatric surgery hypoglycemia” spectrum [1–3]. To our knowledge, this is the first described case of postprandial hyperin- sulinemic hypoglycemia in a child following esophageal reconstruction. Case presentation History of presenting illness A girl at the age of 5 years and 9 months was admitted to our clinic for evaluation of symptomatic hypoglycemia. At the age of 3 years, the parents noticed recurrent brief epi- sodes of pallor, tremor, sweating, fatigue and confusion, which resolved promptly after ingestion of sweet bever- ages and food. Blood sugar was not measured at the time. At the age of 4 years and 11 months, the girl was referred for neurological and cardiological evaluation. The workup included neurological and cardiological exams, EEG, echocardiography and abdominal ultrasound, which all yielded normal results. During her hospital stay, random blood glucose values were measured throughout the day. As no hypoglycemic episodes were detected, the girl was discharged from the hospital and her parents were instructed to continue measuring blood glucose at home. *Corresponding author: Rade Vukovic, MD, PhD, Department of Endocrinology, Mother and Child Health Care Institute of Serbia “Dr Vukan Cupic”, Radoja Dakica 8, 11070 Belgrade, Serbia, Phone: +381113108193, Fax: +381113108257, E-mail: radevukovic9@gmail.com. http://orcid.org/0000-0002-1592-4105 Tatjana Milenkovic, Katarina Mitrovic and Sladjana Todorovic: Department of Endocrinology, Mother and Child Health Care Institute of Serbia “Dr Vukan Cupic”, Belgrade, Serbia Maja Djordjevic and Adrijan Sarajlija: Department of Metabolism and Clinical Genetics, Mother and Child Health Care Institute of Serbia “Dr Vukan Cupic”, Belgrade, Serbia; and School of Medicine, University of Belgrade, Belgrade, Serbia Khalid Hussain: Department of Pediatrics, Division of Endocrinology, Sidra Medical and Research Centre, Doha, Qatar