Zollinger-Ellison Syndrome Unmasked during Hiatal Hernia Evaluation: A Case Report.

Introduction: Zollinger-Ellison syndrome (ZES) is a rare entity consisting of tumors called gastrinomas in the stomach, pancreas, and duodenum. It usually presents with symptoms of acid hyper secretion including abdominal pain, diarrhea, nausea, and vomiting and can be misdiagnosed as peptic ulcer disease, hiatal hernia, and gastroesophageal reflux disease. Case Presentation: We report a case of ZES presenting duodenal perforation and later mimicking a hiatal hernia. This case highlights a complex presentation and underscores the importance of thorough evaluation, multidisciplinary management, and including rare diagnosis in the differential. Our patient presented to the hospital with nausea, back pain, and abdominal pain, and imaging demonstrated a perforated duodenum which was managed with surgical repair. Following surgery, the patient continued to have worsening nausea and acid reflux which was deemed to be due to a hiatal hernia noted on prior imaging until an esophagogastroduodenoscopy (EGD) was performed which confirmed the diagnosis of ZES. Conclusion: Our case emphasizes the importance and necessity of doing an EGD in a timely fashion to ensure that a diagnosis of rare ZES is not missed.