Natural history of asymptomatic bile duct stones and association of endoscopic treatment with clinical outcomes

Background: Due to increasing opportunities for abdominal imaging studies, bile duct stones are occasionally diagnosed without any symptoms. However, there has been no consensus on the management of asymptomatic bile duct stones. We conducted a retrospective longitudinal cohort study to investigate the natural history of asymptomatic bile duct stones and clinical outcomes according to the timing of endoscopic removal. Methods: We identified consecutive patients who were diagnosed with asymptomatic common bile duct stones and categorized into those who were followed up with stones in situ (wait-and-see group) and those who received early endoscopic stone removal (intervention group). Cumulative incidence functions of biliary complications were estimated and compared between the groups. Results: We included 191 patients (114 patients in the wait-and-see group and 77 patients in the intervention group). In the wait-and-see group, the cumulative incidence of biliary complications was 6.1% at 1 year, 11% at 3 years, and 17% at 5 years. Asymptomatic disappearance of stones was observed in 22 patients (19%). Procedure-related adverse events of early endoscopic stone removal of asymptomatic stones were observed in 25 (32%) patients including 4 (5.2%) with severe pancreatitis. The cumulative incidence function of biliary complications did not differ by treatment strategies (P = 0.55). Conclusions: Biliary complications occurred in a substantial proportion of patients with asymptomatic bile duct stones, but early endoscopic removal appeared to have little effect on the prevention of further biliary complications. Given the risk of procedure-related pancreatitis, the wait-and-see strategy may become a management option of asymptomatic stones.