Detection of choledocholithiasis by EUS in acute pancreatitis: a prospective evaluation in 100 consecutive patients

ERCP is the standard for detection of choledocholithiasis in patients with acute biliary pancreatitis, and, if performed early, ERCP decreases morbidity. However, there are procedure-related complications. The aim of the present prospective study was to evaluate the ability of EUS to detect choledocholithiasis in patients presenting with acute pancreatitis.

The study group comprised 100 consecutive patients who presented with acute pancreatitis. EUS, and immediately thereafter, ERCP were performed by separate blinded examiners within 24 hours of admission. The diagnostic accuracy of EUS in identifying gallbladder stones was compared with that of transcutaneous US. The diagnostic accuracy of EUS in detecting choledocholithiasis was then compared with that of US and ERCP based on the results of endoscopic instrumentation of the bile duct after sphincterotomy.

EUS was more sensitive than US in detecting gallbladder stones (100% vs. 84%, p < 0.005). The sensitivities of ERCP and EUS for choledocholithiasis were both 97%, and the overall accuracies were 96% and 98%, respectively, with no significant difference. EUS detected the absence of choledocholithiasis in 65 of 66 patients (specificity = 98%). Endosonographic examination was successful in all patients, whereas ERCP was unsuccessful in 5 patients (p > 0.05). Post-endoscopic sphincterotomy bleeding developed in 4 patients; there was no EUS-related morbidity (p > 0.05).

EUS is more sensitive than US in detecting biliary stones in patients with acute pancreatitis. It is as accurate as ERCP in detecting choledocholithiasis. EUS can be used to select patients with acute pancreatitis who require therapeutic ERCP, thus avoiding diagnostic ERCP and its associated potential for complications in the majority of patients.