AIM: To investigate the frequency and dsk factors for acute pancreatitis after pancreatic guidewire placement (P-GW) in achieving cannulation of the bile duct during endoscopic retrograde cholangio-pancreatography (ERCP).METHODS: P-GW was performed in 113 patients in whom cannulation of the bile duct was difficult.The success rate of biliary cannulation,the frequency and risk factors of post-ERCP pancreatitis,and the fmcluency of spontaneous migration of the pancreatic duct stent were investigated.RESULTS: Selective biliary cannulation with P-GW was achieved in 73% of the patients.Post-ERCP pancreatitis occurred in 12% (14 patients: mild,13; moderate,1).Prophylactic pancreatic stenting was attempted in 59% of the patients.Of the 64 patients who successfully underwent stent placement,three developed mild pancreatitis (4.7%).Of the 49 patients without stent placement,11 developed pancreatitis (22%: mild,10; moderate,1).Of the five patients in whom stent placement was unsuccessful,two developed mild pancreatitis.Univariate and multivariate analyses revealed no pancreatic stenting to be the only significant risk factor for pancreatitis.Spontaneous migration of bhe stent was observed within two weeks in 92% of the patients who had undergone pancreatic duct stenting.CONCLUSION: P-GW is useful for achieving selectivebiliary cannulation.Pancreatic duct stenting after P-GW can reduce the incidence of post-ERCP pancreatitis,which requires evaluation by means of prospective randomized controlled trials.