3023 Necrotizing Pancreatitis Following Ampullary Biopsy Without Biliary Cannulation

Abstract

INTRODUCTION: Patients with familial adenomatous polyposis (FAP) have an almost 100% lifetime risk of developing colorectal cancer (CRC). In addition, they are at increased risk for developing cancers in the duodenum and ampulla. While pancreatitis is a known complication of ampullary manipulation, it typically presents within hours and is relatively mild. We present a unique case of a patient with FAP who underwent an excision biopsy for a diminutive ampullary adenoma and presented with necrotizing pancreatitis 12 days following the procedure. CASE DESCRIPTION/METHODS: A 70-year-old male with a history of FAP and CRC who is status post-total abdominal colectomy was found to have a 2-cm sessile polyp on the lateral wall of the duodenum and a diminutive ampullary polyp (Figure 1) on surveillance esophagogastroduodenoscopy (EGD). The lateral polyp was removed via piecemeal endoscopic mucosal resection. The ampullary polyp was cautiously removed via biopsy excision with an attempt to biopsy along the left lateral margin deliberately away from the tentative pancreatic duct orifice. Both lesions were tubular adenomas. The patient did well for 12 days post-procedure until he presented to the emergency department for epigastric pain, nausea and vomiting. On presentation, serum lipase was 2000 U/L. A CT scan of the abdomen showed necrotizing pancreatitis with an 11-cm peripancreatic fluid collection. The patient denied alcohol use, and imaging did not reveal any cholelithiasis. Serum triglycerides and IgG-4 levels were within normal limits. The patient was admitted, managed with intravenous hydration and early nutrition, and was discharged on hospital day 10. CT abdomen pelvis performed 3 months later showed an 8-cm pancreatic fluid collection consistent with walled-off necrosis (WON). The patient is completely asymptomatic and is being followed clinically with plan for repeat imaging in 3 months. DISCUSSION: Acute pancreatitis is a common complication following endoscopic retrograde cholangiopancreatography (ERCP), but is exceedingly rare without attempts at biliary/pancreatic duct cannulation. In our case, the patient developed necrotizing pancreatitis following an excision biopsy of a diminutive ampullary adenoma without any attempts at cannulation of the ampulla. Patients need to be adequately counseled about the risks of severe pancreatitis, and a high level of suspicion should be maintained for up to two to three weeks after a procedure.