Prognostic factors for recurrence of bile duct stones after endoscopic treatment by sphincter dilation.

BACKGROUND The long-term outcome for patients after endoscopic sphincter of Oddi dilation is poorly documented. This study investigates the recurrence rate for bile duct stones in patients followed for 1 year or more after endoscopic sphincter dilation and stone extraction, and assessed prognostic factors associated with recurrence of ductal calculi. METHODS A total of 169 patients with bile duct stones were treated with endoscopic sphincter dilation between July 1998 and August 2001. Follow-up studies consisted of periodic biochemical tests and out-patient evaluations with endoscopic retrograde cholangiography or magnetic resonance cholangiography performed when follow-up exceeded 1 year. Putative risk factors for stone recurrence included gender, age, stone size and number, associated peripapillary diverticulum, gallbladder status, color of bile duct stones, and bile duct diameter. Statistical analysis consisted of both a Kaplan-Meier estimation and a multivariate Cox regression model. RESULTS Complete stone clearance was achieved in 162 (95.8%) patients, of whom 151 were followed (13 patients died from unrelated disorders). Mean follow-up was 23 months. Stone recurrence was documented in 13 patients. Patients with dilated bile duct or peripapillary diverticulum were at high risk for recurrence. CONCLUSIONS The interval between treatment of bile duct stones by endoscopic sphincter dilation and the recurrence of biliary calculi is relatively short. Bile duct size and peripapillary diverticula are risk factors for early recurrence.