Background: When common bile duct (CBD) stones cannot be removed after conventional endoscopic techniques or mechanical lithotripsy, biliary stenting serves for further planned endoscopic attempt of stone removal or operation. The aim of our study was to investigate the effect of ursodeoxycholic acid (UDCA) or placebo plus endoprostheses on stones' fragmentation or size.
Methods: Forty-one patients with difficult to extract CBD stones were prospectively studied. They were randomised to receive either a 10 Fr straight plastic stent and oral 750 mg UDCA (group A, 21 patients) or placebo (group B, 20 patients) daily for 6 months.
Results: A total clearance of CBD was achieved in 16 patients (76.9%) of group A and 15 patients (75%) of group B. The stones remained unchanged in size in five patients (23.8%) of group A and five patients (25%) of group B. In seven patients (33%) of group A and five patients (25%) of group B a repeated ERCP demonstrated fragmentation of CBD stones that were easily extracted. A reduction in stones' size was observed in 8 patients (38%) of group A (1.61 +/- 0.32 cm before treatment vs. 1.21 +/- 0.24 cm after treatment, p = 0.002) and 10 patients (50%) of group B (1.61 +/- 0.35 cm before vs. 1.24+/-0.22 cm after treatment, p = 0.001). There was no statistically significant difference on stone size reduction (p = 0.602) and fragmentation (p=0.558) between the two groups.
Conclusion: The results of this study suggest that UDCA does not seem to contribute to the reduction in stones' size or stones' fragmentation during the endoprosthetic procedure.