Pancreatic Duct Stent Exchanges via the Minor Papilla for Recurrent Acute Pancreatitis in Pancreas Divisum: How Many is Enough?

Abstract

Introduction: Pancreas divisum is the most common congenital anomaly of the pancreas and can result in recurrent acute pancreatitis (RAP) and chronic pancreatitis. Minor papilla stricture and intraductal hypertension have been proposed to underlie the pathophysiology in this setting. Minor papillotomy with pancreatic duct stenting has shown variable outcomes in patients with divisum and RAP. The specific techniques and protocol are not well defined or homogeneous. This study aims to evaluate procedural factors associated with a favorable outcome. Methods: We conducted a retrospective study on pancreas divisum patients with RAP who underwent minor papillotomy with pancreatic duct stenting from April 2009 to October 2016. Records were reviewed from the index procedure and at subsequent stent exchanges until 6 months after extraction of all stents. Procedural data and stent-related parameters were collected and examined using bivariate analysis. Results: Of 74 patients with pancreas divisum and RAP who underwent minor papillotomy and pancreatic duct stent placement, a total of 163 ERCPs with a mean of 2.3+/-1.6 stent exchanges were performed. 4.29% had post ERCP pancreatitis. Median size and length of the initial stent were 5Fr and 7 cm, while the median final size and length at removal were 7Fr and 8 cm. The mean interval between stent exchanges was 33.7+/-17 days. 53 patients (71.6%) achieved clinical success with no further episodes of pancreatitis during the study period. Comparing between the responder and the non-responder groups, there was no statistically significant difference in age (P=0.64), gender (P=0.91), race (P=0.81), divisum anatomy (complete vs partial; P=0.66), smoking history (P=0.16), alcohol use (P=0.89), or opioid use (0.72). Regarding procedural variables, there was no significant difference in number of stent exchanges (P=0.24), stent configuration (pigtail vs straight; P=0.4), stent diameter (P=0.31), or length of stent (P=0.14). Conclusion: Pancreatic duct stenting for the treatment of RAP in patients with divisum in this cohort yielded a favorable success rate with a low rate of post-ERCP pancreatitis. While an average of 2 stent exchanges per patient with an upsized stent from 5Fr to 7Fr were observed, number of exchanges, type, size, or length of the stent were heterogeneous. The technical aspects of therapeutic stent placement in this setting are not standardized, and it would be of benefit to evaluate the practice parameters in a large group of providers.