ACQUIRED GALLSTONE OPACIFICATION DURING CHOLELITHOLYTIC TREATMENT WITH CHENODEOSCYHOLIC, URSODEOXYCHOLIC, AND TAUROURSODEOXYCHOLIC ACIDS

Objectives: The appearance of gallstone opacification during oral bile acid administration indicates that stones are no longer susceptible t o dissolution and represents, therefore, a definitive treatment failur e. Ursodeoxycholic acid (UDCA) has been imputed to facilitate gallston e opacification; however, data regarding the comparative occurrence of gallstone opacification during UDCA and chenodeoxycholic acid (CDCA) administration are not yet available. Our objectives were to evaluate the frequency of acquired opacification in gallstone patients taking U DCA and in gallstone patients taking CDCA, to verify whether or not ga llstone opacification is a peculiar side effect of UDCA treatment and, further, to evaluate gallstone opacification in gallstone patients re ceiving tauro-UDCA (TUDCA) to verify whether the administration of the more soluble tauroconjugate might prevent the deposition of calcium s alts on the stone surface. Methods: 106 gallstone patients on UDCA, 12 5 gallstone patients on CDCA, and 31 gallstone patients on TUDCA were evaluated. Before treatment, all patients had radiolucent gallstones a s assessed by oral cholecystography; further cholecystographic evaluat ions were performed every 6 months during treatment. Results: The freq uency of gallstone opacification was 13.2% (14/106) in UDCA patients, 8.8% (11/125) in the CDCA patients, and 12.9% (4/31) in the TUDCA pati ents. The differences were not statistically significant (p = NS). Sex , stone size, dose of bile acid, and duration of treatment were not si gnificantly related to an increased frequency of gallstone calcificati on in any of the treatment groups. The frequency of gallstone opacific ation appeared to be higher in older patients. Conclusions: 1) UDCA ri ch bile is not a major predisposing factor for acquired gallstone opac ification; 2) the administration of TUDCA does not prevent gallstone o pacification; 3) opacification could be related to the natural history of gallstone disease.