Correlation Between Elevated Biliary Biomarkers and the Presence of Choledocholithiasis: A Diagnostic Study Using ERCP as the Gold Standard

Abstract

Background: Choledocholithiasis is a common cause of obstructive jaundice and biliary complications. Endoscopic retrograde cholangiopancreatography (ERCP) remains the gold standard for diagnosis and treatment; however, it is an invasive procedure associated with potential complications. Therefore, identifying reliable non-invasive laboratory biomarkers to predict the presence of common bile duct (CBD) stones is essential to optimize patient selection and reduce unnecessary ERCP procedures.

Aim: To evaluate the diagnostic performance of biliary and hepatic biomarkers in predicting choledocholithiasis, using ERCP as the reference gold standard.

Patients and Methods: Prospective cohort included 59 patients who underwent ERCP for suspected choledocholithiasis. Laboratory parameters including alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), total bilirubin, and direct bilirubin were analyzed. Diagnostic performance was assessed using sensitivity, specificity, positive and negative predictive values (PPV and NPV), diagnostic accuracy, and receiver operating characteristic (ROC) curve analysis. Optimal cut-off values were determined using the Youden index.

Results: All biomarkers studied showed statistically significant differences between patients with and without choledocholithiasis (P < 0.05). Total bilirubin demonstrated the highest diagnostic performance among individual markers (AUC = 0.85), followed by direct bilirubin and GGT. Liver transaminases (ALT and AST) showed lower diagnostic accuracy.

Conclusion: Total bilirubin and GGT are reliable biomarkers for predicting choledocholithiasis. Utilizing these markers may improve clinical decision-making and help reduce unnecessary ERCP procedures in patients with suspected CBD stones.