***TASK*** the task is to summarize an input biomedical literature in six sentences 
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    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Increased circulating levels of hepatotoxic bile acids may contribute to the cholestasis characteristic of cystic fibrosis-related liver disease . The aims of this study were to compare serum bile acid profiles in patients with cystic fibrosis with and without liver disease , and to evaluate the effect of treatment with ursodeoxycholic acid , a non-hepatotoxic bile acid , on liver biochemistry and serum bile acids in patients with cystic fibrosis-related liver disease .  Fasting and postpr and ial serum bile acid levels were analysed in 15 patients ( nine males ; median age 18 years ) with cystic fibrosis-related liver disease and compared with serum bile acid levels in 18 cystic fibrosis patients ( 12 males ; median age 22 years ) without liver disease and 10 control subjects .  Fasting and postpr and ial serum levels of primary and secondary serum bile acids were analysed using high-performance liquid chromatography . Liver biochemistry and serum bile acids were measured in six cystic fibrosis patients with liver disease before and 6 months after treatment with ursodeoxycholic acid 20 mg/kg/day and compared with six control patients with cystic fibrosis-related liver disease . Total fasting and postpr and ial serum bile acid levels were significantly ( P < 0.01 ) elevated in patients with liver disease compared to those without liver disease and controls . The fasting glycine conjugates of cholic acid , chenodeoxycholic acid and deoxycholic acid , and the fasting and postpr and ial taurine conjugates of cholic acid and chenodeoxycholic acid were significantly ( P < 0.05 ) elevated in liver disease patients compared to patients without liver disease and controls . After 6 months ' treatment with ursodeoxycholic acid , although the serum was significantly saturated with ursodeoxycholic acid and significant improvements in liver biochemistry were observed in the treatment group , there was no significant reduction in the levels of individual serum bile acids . Although circulating levels of potentially hepatotoxic serum bile acids are elevated in patients with cystic fibrosis-related liver disease , improvements in liver biochemistry associated with ursodeoxycholic acid treatment can not be attributed solely to alterations in levels of endogenous bile acids Liver disease is increasingly recognized as a major cause of morbidity in cystic fibrosis ( CF ) . Preliminary data suggest that ursodeoxycholic acid ( UDCA ) may be beneficial for treatment of this manifestation . We performed a double-blind , multicenter trial in these patients to establish efficacy and safety of UDCA in terms of the improvement of clinical and nutritional indicators besides st and ard liver function tests . We also intended to establish whether taurine supplementation has a beneficial effect in patients receiving UDCA . From June to December 1990 , we enrolled in 12 centers 55 CF patients with liver disease ( 39 male subjects ; median age , 13.8 years ) . They were r and omly assigned to receive for 1 year one of the following treatments : UDCA ( 15 mg/kg body weight daily ) plus taurine ( 30 mg/kg body weight daily ) , UDCA plus placebo , placebo plus taurine , or double placebo .  Clinical and laboratory evaluations were performed every 3 months . After 1 year , deterioration of overall clinical conditions , as indicated by the Shwachman-Kulczycki score ( SKS ) , occurred in patients who received placebo but not in those who received UDCA ( P = .025 ) . Patients treated with UDCA also showed an improvement in gamma-glutamyl transpeptidase ( GGT ) ( P = .004 ) and 5'-nucleotidase ( P = .006 ) levels . Treatment with taurine was followed by a significant increase in serum prealbumin levels ( P = .053 ) , a trend toward a reduction in fat malabsorption , and no effect on the biochemical profile . No severe side effects occurred with any treatment . Thus , we concluded that UDCA administration improves clinical and biochemical parameters in CF patients with liver disease .  Taurine supplementation may be indicated in patients with severe pancreatic insufficiency and poor nutritional status Ursodeoxycholic acid administration has been reported to improve cholestasis and inflammatory activity in primary biliary cirrhosis and , in an uncontrolled study , also in young adults with cystic fibrosis ( CF ) and chronic cholestasis . As an improvement in nutritional status was also observed in these young adult patients , we investigated whether the administration of a medium dose of ursodeoxycholic acid ameliorates the nutritional status of malnourished young adult CF patients with chronic liver disease . The study included 51 patients ( 27 male patients and 24 female patients ; age range , 8–32 years ; median , 14 ) with body mass percentiles < 90 % . Patients were r and omly assigned to receive either ursodeoxycholic acid ( 10–12 mg/kg/day ) alone or with taurine ( 18–22 mg/kg/day ) . Patients were followed in a crossover fashion within each group ; 6 months of treatment was r and omly alternated with 6 months of placebo .  Nine patients dropped out before concluding the study .  Liver function tests , nutritional status , and coefficients of fat absorption were determined at entry and after each 6 months of placebo or treatment .  Nutritional status and fat absorption were not significantly modified by either treatment . Liver function tests improved after ursodeoxycholic acid administration only in patients with concomitant chronic liver disease . Our findings indicate that 6 months of therapy with a medium dose of ursodeoxycholic acid , either alone or with taurine , does not improve the nutritional status of young malnourished CF patients . Higher doses given for longer periods might be worth investigating BACKGROUND Ursodeoxycholic acid ( UDCA ) is beneficial in cholestasis related to cystic fibrosis ( CF ) . High-dose treatment has been recommended to compensate for bile salt malabsorption . We compared the results of low-dose ( 10 mg/kg/day ) and high-dose ( 20 mg/kg/day ) UDCA treatment on liver biochemistry after 3 and 12 months ' treatment . METHODS Thirty CF patients ( age > 5 years ) with biochemical cholestasis and compensated liver disease were r and omized for low-dose ( n = 17 ) or high-dose ( n = 13 ) UDCA . Baseline clinical variables were comparable . RESULTS After 1 year one patient had died of liver failure ( low dose ) , and three had dropped out because of pruritus ( one in each group ) or personal choice ( low dose ) . In the high-dose group improvement in gamma-glutamyl transferase values was more pronounced after 3 months and 1 year ( P < 0.004 ) , and improvement of alanine aminotransferase was better after 1 yer ( P < 0.02 ) . Improvement of alkaline phosphatase and aspartate aminotransferase was comparable . Complete normalization of liver enzymes and bilirubin occurred more often in the high-dose group . CONCLUSION High-dose UDCA induces a better response of liver biochemistry values than low-dose UDCA in CF patients with cholestatic liver disease The efficacy and safety of ursodeoxycholic acid for the treatment of primary sclerosing cholangitis were evaluated in a prospect i ve , r and omized , double-blind , placebo-controlled trial . Fourteen patients with primary sclerosing cholangitis documented by cholestatic serum enzyme pattern , liver histological appearance and endoscopic retro grade cholangiography were included in the trial . Six patients received ursodeoxycholic acid ( 13 to 15 mg/kg body wt/day ) , and eight patients received placebo . Two patients had to be withdrawn from the study , one because of UDCA-related diarrhea and the other because of worsening of the disease during placebo treatment . Patients in the ursodeoxycholic acid group improved significantly during 1 yr of treatment with respect to serum levels of bilirubin ( median = -50 % ) , alkaline phosphatase ( median = -67 % ) , gamma-glutamyltransferase ( median = -53 % ) , AST ( median = -54 % ) and ALT ( median = -36 % ) compared with the placebo group , but not with respect to serum levels of hydrophobic bile acids . During ursodeoxycholic acid treatment , histopathological features also improved significantly , as evaluated by multiparametric score . Expression of human leukocyte antigen class I molecules appeared to be markedly reduced on liver cells after ursodeoxycholic acid treatment . We conclude that ursodeoxycholic acid is beneficial in reducing disease activity in patients with primary sclerosing cholangitis Previous studies from our groups have demonstrated improvements in biochemical markers of liver function when cystic fibrosis patients with associated liver disease were administered oral ursodeoxycholic acid . The magnitude of the response was somewhat less than that found when comparable doses ( 10 to 15 mg/kg body wt/day ) of ursodeoxycholic acid are given to other liver disease patients ; this may be explained by the bile acid malabsorption that is characteristic of the disease . For this reason a dose-response study was carried out in nine cystic fibrosis patients with liver disease to establish whether improved efficacy could be obtained with higher doses . Ursodeoxycholic acid in doses of 5 , 10 and 15 mg/kg body wt/day was given orally for consecutive 2-mo periods in a replicated Latin-square design . After this , all patients received 20 mg/kg body wt/day . Liver function , individual serum bile acids and biliary bile acid composition were determined at entry and at the end of each treatment period . Our data demonstrate that the magnitude of the biochemical improvement in serum liver enzymes was significantly greater with higher doses of ursodeoxycholic acid ; at 20 mg/kg body wt/day it was similar to that reported for patients with other liver diseases administered lower doses . Biliary ursodeoxycholic acid enrichment increased with increasing doses , attaining 42 % + /- 6 % of the total biliary bile acids with the highest dose . Fasting serum ursodeoxycholic acid concentrations increased during ursodeoxycholic acid administration but were variable and correlated poorly with the dose of ursodeoxycholic acid administered , whereas no correlation was found between serum ursodeoxycholic acid concentration and the proportion of ursodeoxycholic acid in bile . ( ABSTRACT TRUNCATED AT 250 WORDS Cholesterol gallstones are dissolved in man by chenodeoxycholic acid ( CDCA ) and ursodeoxycholic acid ( UDCA ) . To test the comparative efficacy of these two cholelitholytic bile acids , 223 gallstones patients were r and omly treated with either UDCA or CDCA at two different doses : 7 to 8 mg per kg per day and 14 to 15 mg per kg per day . Efficacy and factors influencing dissolution ( dose , size of the stones , and time ) were evaluated after 3 , 6 , and 12 months of treatment . UDCA was significantly more efficacious than was CDCA after 3 and 6 months of treatment , whereas after 12 months , no significant differences were observed . UDCA was equally effective at high and low doses , both on small and large stones . CDCA  was significantly more effective at high doses and on small stones . Seventy-four per cent of the total dissolutions with UDCA and 42 % with CDCA occurred within the first 6 months of treatment . Diarrhea and hypertransaminasemia occurred only in the CDCA-treated patients . We conclude that UDCA seems to be the bile acid of choice in dissolving cholesterol gallstones This was a prospect i ve open study that examined the quantitative and qualitative analysis of hepatobiliary scintigraphy ( DISIDA ) in detecting liver involvement in cystic fibrosis ( CF ) . Forty-four adult and pediatric patients ( median age , 12.1 years ; range , 1.1 - 36.3 years ) were divided into three groups : group 1 , no evidence of liver involvement ( n = 8) ; group 2 , biochemical evidence of liver involvement on two or more occasions ( n = 26 ) ; and group 3 , clinical evidence of liver disease ( n = 10 ) . In groups 1 and 2 , the most common qualitative scintigraphic finding was focal intrahepatic retention of tracer ( 26/34 patients , 12 of whom had normal findings on ultrasonography ) . This finding corresponds to focal cholestasis and may warrant treatment with the choleretic agent ursodeoxycholic acid ( UDCA ) . In the group 3 patients , the abnormal qualitative scintigraphic appearances ( heterogeneous uptake of tracer and nodular liver outline ) added little to the findings on ultrasonography ; however , these patients had a prolonged mean hepatic clearance time compared with those in groups 1 and 2 ( one-way ANOVA ; P < .015 ) . It is proposed that scintigraphy with DISIDA has a role in the detection of early liver involvement in cystic fibrosis BACKGROUND In primary biliary cirrhosis the hepatic lesions may result , at least in part , from the intracellular accumulation of potentially toxic endogenous bile acids . Preliminary work suggests that the administration of ursodiol ( also called ursodeoxycholic acid ) , a hydrophilic bile acid without hepatotox 
    Output:
    
There is insufficient evidence to justify is its routine use in cystic fibrosis