2136 The Migrating and Perforating Biliary Stent

Abstract

INTRODUCTION: Although there are high success rates with biliary endoprostheses, there is also accumulating evidence of short and long term complications including: sepsis, migration, perforation, fistula formation and bowel obstruction. This case report presents successful nonsurgical intervention of a rare but grave complication following biliary stent placement. CASE DESCRIPTION/METHODS: A 78 year old male with choledocholithiasis underwent an ERCP with incomplete stone removal, necessitating a 10Fr x 5 cm double-pigtail stent. Repeat ERCP at 6 weeks and an abdominal x-ray suggested distal migration of the stent. Despite multiple laxatives, a followup CT scan confirmed stent retention localized to the IC valve. Although he remained asymptomatic, colonoscopy was pursued and unexpectedly revealed one end of the stent penetrating terminal ileum mucosa, with the other end transecting the serosal surface and perforating through the cecum. The stent was removed with a snare and hemostatic clips were placed to close the defect. At 6 months, he continues to do well without any complications. DISCUSSION: Stent migration occurs in up to 10% of cases, with less than 1% risk of perforation. Short stents tend to travel proximally while longer stents tend to travel distally causing abdominal pain or bowel obstruction. Stent length (>7 cm), benign strictures, sphincter of Oddi dysfunction, post-sphincterotomy and papillary stenosis have all been associated with higher rates of distal migration. Most stents will pass uneventfully into excreta. Rarely, bowel perforation can occur. The duodenum is the most reported site of perforation due to its fixed setting. However, there have been close to a dozen cases of colonic perforation. Both stent design and patient’s anatomy can be obvious risk factors. Straight plastic stents have been associated with higher risk as compared to metal or pigtail stents. Anatomic aberrancies such as abdominal hernias, extensive adhesions and colonic diverticulae are associated with higher risk. Our case highlights bizarre stent migration/perforation with a theoretically lower risk stent, in an asymptomatic patient without known risk factors. Despite this precarious scenario, endoscopic intervention without surgery was sufficient. The collection of case reports in the literature, including our own, suggests the need for guidelines outlining appropriate measures (e.g. followup intervals for repeat imaging) and guidelines outlining management of biliary endoprostheses complications.