Detection of biliary origin of acute pancreatitis. Comparison of laboratory tests, ultrasound, computed tomography, and ERCP.

Fifty consecutive patients with acute pancreatitis were assessed with respect to a biliary origin of the disease. Endoscopic retrograde cholangiopancreaticography, surgery, and autopsy were used to define biliary pancreatitis. Ultrasound, computed tomography, and several laboratory tests (SGOT, SGPT, alkaline phosphatase, and bilirubin) were analyzed for their ability to detect a biliary origin of the disease. Ultrasound and computed tomography could not reliably make the diagnosis in the 10 patients found to have biliary disease. Receiver-operator-characteristic curves revealed that none of the laboratory tests assessed had sufficient sensitivity and specificity to determine the diagnosis, although all tests showed higher mean values in biliary pancreatitis. SGPT gave the best discrimination (positive predictive value 53%, negative predictive value 94%, cut off 40 units/liter). Therefore, initial ERCP is suggested for a reliable diagnosis of biliary origin of acute pancreatitis.