Ultrasonographic evaluation of the common bile duct in biliary acute pancreatitis patients: comparison with endoscopic retrograde cholangiopancreatography.

We compared the morphologic findings of the common bile duct by ultrasonography and endoscopic retrograde cholangiopancreatography in patients with biliary acute pancreatitis. Forty-five patients were studied. The diagnosis of acute pancreatitis was based on the presence of characteristic abdominal pain associated with an elevation of serum amylase and lipase concentrations. All patients underwent ultrasonography and subsequently urgent endoscopic retrograde cholangiopancreatography and eventually endoscopic sphincterotomy. Ultrasonography showed gallstones in 33 patients and sludge of the gallbladder in seven patients. In the common bile duct, lithiasis was found in two patients and sludge in 25. Endoscopic retrograde cholangiopancreatography showed choledocolithiasis in eight patients and sludge of the common bile duct in 32. In 27 cases (60%) concordance occurred between ultrasonographic and endoscopic retrograde cholangiopancreatographic detection of lithiasis or sludge of the common bile duct. The average diameter of the common bile duct determined by sonography was significantly smaller (P < 0.001) than that obtained by endoscopic retrograde cholangiopancreatography. The evaluation of this parameter indicated that a good correlation existed between the values obtained with the two techniques (r(s) = 0.765, P < 0.001). Both ultrasonography and endoscopic retrograde cholangiopancreatography can provide reliable measurements of the common bile duct diameter. Ultrasonography is the technique of choice in the initial investigation of patients with biliary acute pancreatitis.