Do normal findings at biliary endoscopic ultrasonography obviate the need for endoscopic retrograde cholangiography in patients with suspicion of common bile duct stone? A prospective follow-up study of 238 patients.

Abstract

Biliary endoscopic ultrasonography (EUS) and endoscopic retrograde cholangiography (ERC) are equally accurate for the diagnosis of common bile duct (CBD) stone. The aim of this prospective 1-year follow-up study was to determine whether normal findings at initial EUS obviated the need for ERC. During a 17-month period, all patients referred for biliary EUS because of suspicion of CBD stone, in whom EUS findings were normal were included in the study. Early (1-month) and late (1-year) follow-up details were obtained by mail or telephone. The clinical course and need for ERC were recorded. 238 patients were enrolled. During follow-up, 59 (25 %) patients underwent cholecystectomy, with (n=31) or without (n=28) cholangiography, and 30 patients underwent ERC (13 %). CBD stone was found in 14 (6 %) patients. Of these 30 patients, ERC was done in 15 cases in the first week after EUS, because of persistent suspicion of a CBD stone which was found in 10 patients. The 15 late ERC procedures (carried out more than 1 week after EUS) revealed only one CBD stone. The negative predictive value of EUS for the diagnosis of CBD stones was 95.4 %. Patients with suspicion of CBD stones but normal EUS findings have a low risk of needing ERC in a 1-year period.