The utility of endoscopic ultrasound in detecting missed common bile duct stones

Backgroundand aim Accurate procedures for recognizing common bile duct (CBD) and pancreatic conditions are essential to manage proper interventions. We aimed to assess the utility of endoscopic ultrasound (EUS) and magnetic resonance cholangiopancreatography (MRCP) in discovering CBD stones compared with endoscopic retrograde cholangiopancreatography (ERCP). Patients and methods This prospective multicenter study included 200 patients over 18 years old with dilated CBD measuring 6–10 mm, unexplained elevated liver enzymes (ALT more than 55 U/L, AST more than 48 U/L), and unexplained acute pancreatitis (amylase elevated more than 86 U/L, and lipase elevated more than 59 U/L, respectively). The patients were evaluated using abdominal ultrasonography, MRCP, and EUS. MRCP is performed just before the EUS and the ERCP being performed at a subsequent stage whenever indicated. Results Stones were discovered in 39.5% of the patients using ERCP compared with 47% using MRCP and 43.5% using EUS. There was a strong agreement between ERCP findings and EUS findings (Kappa=0.837). EUS can notably distinguish stones with a sensitivity of 94.9%, specificity of 90.1%, positive predictive value of 86.2%, negative predictive value of 96.5%, and accuracy of 92%. There was a moderate agreement between ERCP findings and MRCP findings (Kappa=0.402). MRCP can significantly detect stones with a sensitivity of 72.2%, specificity of 69.4%, positive predictive value of 60.6%, negative predictive value of 79.2%, and accuracy of 70.5%. The accuracy of EUS was significantly higher than accuracy of MRCP. Conclusions EUS is a more accurate diagnostic device for detecting stones compared with MRCP, and it has a strong agreement with ERCP findings, which is considered the gold standard.