Bilirubin-based decision-making for MRCP use in acute biliary pancreatitis: a retrospective cohort study

Background Differentiating cholangitis and determining the necessity of biliary drainage in acute biliary pancreatitis accompanied by hyperbilirubinemia remains clinically challenging. Although magnetic resonance cholangiopancreatography (MRCP) is frequently used, standardized bilirubin thresholds guiding its use have not been clearly defined. Methods This retrospective observational cohort study included 158 patients diagnosed with acute biliary pancreatitis and hyperbilirubinemia who underwent MRCP between January 2017 and December 2019. Patients were categorized according to MRCP findings and endoscopic retrograde cholangiopancreatography (ERCP) requirement. Demographic characteristics, pancreatitis severity, laboratory parameters, clinical outcomes, and complications were analyzed. Receiver operating characteristic (ROC) curve analysis and Youden’s J index were used to determine optimal bilirubin cut-off values. Results MRCP demonstrated high diagnostic accuracy, with a sensitivity of 95.45% and specificity of 98.13%. The optimal bilirubin thresholds indicating the need for MRCP were identified as total bilirubin ≥ 3.78 mg/dL and direct bilirubin ≥ 2.80 mg/dL. Conclusion A bilirubin-based clinical decision-making algorithm may optimize MRCP utilization and reduce unnecessary ERCP procedures in patients with acute biliary pancreatitis.