Endocrine Abstracts

Background: Fundoplication is a common surgical procedure used to treat severe gastroesophageal reflux disease and large hiatus hernias. Reactive hypoglycaemia, a form of late dumping syndrome characterized by postprandial insulin surges and resulting hypoglycaemia, is uncommon after fundoplication. This case presents a rare instance of this complication in an elderly patient.

Case Description: A 73-year-old male with a large sliding hiatus hernia underwent elective fundoplication following persistent GERD symptoms unresponsive to proton pump inhibitors. The surgery was uncomplicated, and the patient was discharged on postoperative day 2. In the following months, he reported improvement in reflux symptoms and returned to a regular diet. Approximately 4 months postoperatively, the patient began experiencing episodes of dizziness, palpitations,sweating, and confusion occurring 1.5 to 3 hours after meals. These episodes were transient and resolved spontaneously or with carbohydrate intake. There was no history of diabetes mellitus or use of glucose-lowering medications.

Clinical Hypothesis: Reactive hypoglycaemia post-upper GI surgery is most commonly associated with bariatric procedures due to rapid gastric emptying and exaggerated insulin responses.

Diagnostic Pathway: Capillary blood glucose readings during symptomatic episodes revealed hypoglycaemia with values ranging from 2.1 to 3.0 mmol/l. Fasting glucose: 4.9 mmol/l. Postprandial glucose (90 mins): 3.2 mmol/l Insulin level (90 mins): Inappropriately elevated for glucose level C-peptide: Normal. HbA1c: 34 mmol/mol. The symptoms completely resolved with Tirzeperatide.

Discussion and Learning Points: This case underscores the need to consider postprandial hypoglycaemia in the differential diagnosis of unexplained neurological or autonomic symptoms following fundoplication.