Risk Stratification for the Development of Post-ERCP Pancreatitis by Sphincter of Oddi Dysfunction Classification

OBJECTIVES: To explore whether there is a difference in the frequency of postendoscopic retrograde cholangiopancreatography (ERCP) pancreatitis in patients with manometrically confirmed sphincter of Oddi dysfunction (SOD) types I, II, and III. METHODS: A retrospective review of all of the patients who underwent an ERCP with SOD type I or patients with manometrically confirmed SOD type II or type III (mean basal sphincter pressure ≥ 40 mm Hg) from 2006 to 2010 was performed. The primary outcome measure was development of post-ERCP acute pancreatitis in each of the SOD groups. Factors associated with acute pancreatitis in each group were examined by univariate analysis. RESULTS: We identified 147 patients with SOD. Biliary sphincterotomy was performed in all of the patients, and pancreatic sphincterotomy was performed in 68 of the 147 (46%). All of the patients underwent stenting of the pancreatic duct. Post-ERCP pancreatitis occurred in 23% of the study cohort. Patients with SOD type III had a higher frequency of post-ERCP pancreatitis compared with the SOD type I and type II groups (31% vs 20% vs 6%, respectively; P = 0.024). Those with SOD type III had a greater frequency of post-ERCP pancreatitis (odds ratio 6.7; P = 0.05) compared with those with SOD type I. Patients with SOD type III had a two times greater frequency of developing post-ECRP pancreatitis compared with those with SOD type II. CONCLUSIONS: SOD type III is strongly associated with the development of post-ERCP pancreatitis compared with SOD type I.