New practical scoring system to predict post-endoscopic retrograde cholangiopancreatography pancreatitis: Development and validation

Background and Aim: Post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) is the most serious adverse event of ERCP. Therefore, it is important to identify high-risk patients who require prophylactic measures. The aim of this study was to develop a practical prediction model for PEP that identifies high-risk patients. Methods: Patients who underwent ERCP at three tertiary hospitals between April 2010 and September 2012 were enrolled. The dataset was divided into a training set (two centers) and validation set (one center). Using the training set, univariable and multivariable analyses were performed to identify predictive factors for PEP. We constructed a scoring system and evaluated reproducibility using the validation set. Results: A total of 2719 ERCPs were analyzed. PEP developed in 133 cases (4.9%). Risk factors (adjusted odds ratios [OR]) in the training set were a history of PEP (OR: 4.2), intact papilla (OR: 2.4), difficult cannulation (OR: 1.9), pancreatic guidewire-assisted biliary cannulation (OR: 2.2), pancreatic injection (OR: 2.1), pancreatic intraductal ultrasonography (IDUS)/sampling from the pancreatic duct (OR: 2.2), and biliary IDUS/sampling from the biliary tract (OR: 2.8). A scoring system was constructed using these seven clinical variables. The areas under the receiver-operating characteristic curve of this model were 0.799 in the training set and 0.791 in the validation set. In the high-risk group at a score of 3 or higher, the incidence of PEP was 13.4%, and all severe/fatal cases were in the high-risk group. Conclusions: This scoring system helps to predict each patient's risk and select preventive measures.