HYPOGLYCEMIA RESOLUTION AFTER A BIOCHEMICALLY CONFIRMED, HISTOLOGY-NEGATIVE PANCREATIC INSULINOMA SURGERY:

A CASE REPORT

Abstract

CASE
A 50-year-old 80-kg Filipino female presented with blank stares and hypoglycemia resolving after intravenous glucose infusion. A 72-hour fast revealed hypoglycemia (43.90 mg/dL) and elevated serum C-peptide (5.90 ng/mL) and serum insulin (60.86 µIU/mL) after 14 hours, confirming hyperinsulinemic hypoglycemia. Abdominal CT showed a 1.4 x 1.3 x 1.3 cm exophytic, isodense nodule along the inferior margin of the pancreatic body. Endoscopic ultrasound also revealed a 1.0 x 1.7 cm hypoechoic pancreatic nodule. She underwent a distal pancreatectomy. Investigation of unresolved hypoglycemia revealed a persistent pancreatic nodule, prompting extended pancreatectomy with intraoperative ultrasound guidance. Post-operatively, hypoglycemia no longer recurred. Histopathology revealed benign pancreatic tissue with fat necrosis, hemorrhage and microcalcifications. Six months postoperatively, she had 21% weight loss. No pancreatic nodule was visualized on repeat CT. The negative histopathologic findings may be due to the early stages of insulinoma or the beginning of hyperplasia. Post-operative weight loss may indicate successful insulinoma resection.