Ductal stones recurrence after extracorporeal shock wave lithotripsy for difficult common bile duct stones: Predictive factors

Background & purpose Extra-corporeal shock wave lithotripsy (ESWL) can be considered in difficult common bile duct stones (DCBDS), with a success rate greater than 90% but data on stone recurrence after ESWL are limited. We performed a retrospective analysis to evaluate long-term outcomes in patients who underwent ESWL for DCBDS. Methods From May 1992 to October 2012, patients who underwent ESWL treatment for DCBDS, not amenable to endoscopic extraction, were included. Data on long-term outcome were collected through phone interviews and medical records. Results A total of 201 patients with a successful clearance of DCBDS after ESWL were included. During a median follow-up period of 4.64 years, 40 patients (20%) developed a recurrence of bile duct stones. Logistic regression analysis showed that the common bile duct diameter, gallstones presence and the maximum stone size were significantly associated with recurrence. Conclusions We observed a recurrence rate of 20% over a median follow-up of 4 years. Gallbladder stones, stone size and a dilated common bile duct diameter are risk factors for recurrent stone formation, while ursodeoxycholic acid treatment did not influence recurrence in our population.