Nucleation time, cholesterol saturation index, and biliary bile acid pattern. A comparison in responders and nonresponders to systemic litholysis with bile acids.

In a 24-month trial of a combination therapy with ursodeoxycholic acid and chenodeoxycholic acid complete dissolution of radiolucent gallstones was achieved in 15 of 55 patients (27.3%). A decrease of stone volume of greater than 35% was achieved in a further 28 patients (50.9%). In 12 patients (21.8%) inadequate compliance (3.6%), a nonfunctioning gallbladder (3.6%), absence of size decrease (10.9%), or acute cholecystitis (3.6%) required interruption of therapy. Determination of the cholesterol saturation index (CSI) did not facilitate patient selection, nor was there a statistically significant difference between responders and nonresponders to dissolution therapy. In the course of treatment the average CSI showed a statistically significant decrease from 1.54 +/- 0.12 to 0.82 +/- 0.06 (p less than 0.001). Patients in whom complete dissolution was achieved and those in whom no improvement was observed differed significantly in nucleation time (4.7 +/- 0.8 versus 15.0 +/- 2.2 days; p less than 0.001) and initial gallstone volume (274 +/- 78 versus 1045 +/- 180 mm3). The nucleation time increased statistically significantly during the therapy in the successfully treated group. The percentages of glycocholic acid (8.1 +/- 1.13 versus 4.1 +/- 0.55%; p less than 0.01), taurocholic acid (2.2 +/- 0.45 versus 0.8 +/- 0.23%; p less than 0.05), and glycodeoxycholic acid (4.9 +/- 0.70 versus 1.4 +/- 0.37%; p less than 0.001) were statistically significantly different after the treatment. There were no statistically significant differences between patients with complete and incomplete stone dissolution with regard to age, mean body weight, or laboratory variables.