Does endoscopic sphincterotomy reduce the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis after biliary stenting? A systematic review and meta-analysis

Background and Aim Endoscopic biliary sphincterotomy (ES) is often carried out prior to placement of a biliary stent apparently to reduce the risk of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). However, the protective effect of ES prior to biliary stenting is controversial. The objective of this meta-analysis is to compare the risk of PEP and other complications after the placement of biliary stent with or without ES in patients with biliary obstruction and bile leak. Methods We carried out a systematic search in several electronic databases for randomized controlled trials (RCT) and observational studies (OS) comparing the risk of PEP after biliary stenting with or without ES. The Mantel-Haenszel method was used to pool data of adverse outcomes into fixed or random effect model meta-analyses. Results Seventeen studies (five RCT and 12 OS) with a total of 2710 patients met the inclusion criteria. No significant difference was observed in the risk of PEP with biliary stenting with and without ES (RD -0.01; 95% confidence interval [CI] -0.03, 0.01). In a subgroup analysis of stenting for biliary obstruction, no difference in the risk of PEP was observed with or without ES. However, ES was associated with lower risk of PEP in patients undergoing biliary stenting for bile leak (RD -0.05; CI -0.10, -0.01). Conclusions ES shows risk reduction in prevention of PEP in patients undergoing endoscopic stenting for bile leak. However, placement of biliary stent without ES is not associated with an increased risk of PEP in patients with distal bile duct obstruction with involvement of pancreatic duct.