Zollinger-Ellison Syndrome: A Rare Case of Chronic Diarrhea.

Zollinger-Ellison syndrome (ZES) is caused by hypersecretion of gastrin from duodenal or pancreatic gastrinomas. We report a case of a 57-year-old female who presented with chronic diarrhea. CT abdomen showed multiple liver masses. Liver biopsy suggested metastatic well-differentiated neuroendocrine tumor. Serum gastrin level was markedly elevated. MRI abdomen, somatostatin receptor scintigraphy and endoscopic ultrasound failed to reveal primary site of the tumor. Upper gastrointestinal endoscopy showed hyperplastic gastric folds and multiple duodenal ulcers consistent with ZES. Patient was started on high-dose omeprazole and octreotide resulting in improvement in diarrhea.