Identifying patients most likely to have a common bile duct stone after a positive intraoperative cholangiogram

The false-positive rates of a positive intraoperative cholangiogram (IOC) are as high as 60%. Endoscopic retrograde cholangiopancreatography (ERCP) for stone removal is required after a positive IOC. It is unclear which clinical factors identify patients most likely to have a stone after a positive IOC. This study was conducted to identify factors predictive of common bile duct (CBD) stone(s) on ERCP after a positive IOC. A retrospective review of our endoscopic database identified all ERCP and/or endoscopic ultrasound (EUS) procedures performed for a positive IOC between August 2003 and August 2009. Collected data included patient demographics; indication for cholecystectomy; IOC findings; blood tests before and after cholecystectomy, including liver function tests, complete blood count, and amylase and lipase measurements; and ERCP and/or EUS results. Patients who had a negative EUS for CBD stones and no subsequent ERCP were contacted by phone to see if they eventually required an ERCP. Univariate and multi-variable analyses were performed. A total of 114 patients were included in the study. IOC findings included a single stone, multiple stones, nonpassage of contrast into the duodenum, dilated CBD, and poor visualization of the bile duct. Eighty-four percent of patients had ERCP only, 9% had EUS only, and 7% had EUS followed by ERCP. Sixty-five patients (57%) had CBD stones on ERCP or EUS. Older age, multiple stones, dilated CBD on IOC, and elevated postcholecystectomy bilirubin levels were the clinical variables with statistically significant differences on univariate analysis. On multivariable analysis, older age and elevated postcholecystectomy total bilirubin levels correlated with the presence of CBD stones on ERCP. Fifty-seven percent of patients referred for endoscopic evaluation after a positive IOC had CBD stones on ERCP. Patients with CBD stones after a positive IOC were more likely to be older with elevated post-cholecystectomy total serum bilirubin levels.