Effects of ursodeoxycholic acid on liver function in patients with cystic fibrosis and chronic cholestasis

Cystic fibrosis screening, evaluation, and management of hepatobiliary disease consensus recommendations

Cystic fibrosis (CF) may cause a spectrum of hepatobiliary complications, including portal hypertension, multilobular cirrhosis, and liver failure. Current guidelines on the detection and monitoring of hepatobiliary complications in CF were published in 1999. The CF Foundation assembled a committee to evaluate research advances and formulate revised guidelines for CF-associated liver disease. A committee of hepatologists, gastroenterologists, pulmonologists, pharmacists, nurses, dietitians, individuals with CF, and the parents of a child with CF devised "population, intervention, comparison, and outcome" questions regarding hepatobiliary disease in CF. PubMed literature searches were performed for each population, intervention, comparison, and outcome question. Recommendations were voted on with 80% agreement required to approve a recommendation. Public comment on initial recommendations was solicited prior to the formulation of final recommendations. Thirty-one population, intervention, comparison, and outcome questions were assembled, 6401 manuscripts were title screened for relevance, with 1053 manuscripts undergoing detailed full-text review. Seven recommendations were approved for screening, 13 for monitoring of existing disease, and 14 for treatment of CF-associated hepatobiliary involvement or advanced liver disease. One recommendation on liver biopsy did not meet the 80% threshold. One recommendation on screening ultrasound was revised and re-voted on. Through a multidisciplinary committee and public engagement, we have assembled updated recommendations and guidance on screening, monitoring, and treatment of CF-associated hepatobiliary involvement and advanced liver disease. While research gaps remain, we anticipate that these recommendations will lead to improvements in CF outcomes through earlier detection and increased evidence-based approaches to monitoring and treatment.

Current Treatment Options for Cystic Fibrosis-Related Liver Disease

Cystic Fibrosis-related liver disease (CFLD) has become a leading cause of morbidity and mortality in patients with Cystic Fibrosis (CF), and affects children and adults. The understanding of the pathogenesis of CFLD is key in order to develop efficacious treatments. However, it remains complex, and has not been clarified to the last. The search for a drug might be additionally complicated due to the diverse clinical picture and lack of a unified definition of CFLD. Although ursodeoxycholic acid has been used for decades, its efficacy in CFLD is controversial, and the potential of Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) modulators and targeted gene therapy in CFLD needs to be defined in the near future. This review focuses on the current knowledge on treatment strategies for CFLD based on pathomechanistic viewpoints.

Study of quality and stability of ursodeoxycholic acid formulations for oral pediatric administration

This paper describes a rational method of characterizing the biopharmaceutical stability of two oral suspensions of ursodeoxycholic acid (UDCA) used in pediatrics. Because there is no commercial presentation of UDCA that can administer appropriate doses for infants and children, an active pharmaceutical ingredient (API) formulation is required. Due to its very low solubility and low dose in the formula (1.5%), two different suspensions with minimal use of excipients were studied, avoiding the use of complex additives and those not recommended by the European Medicines Agency (EMA). Adherence to Standard Operating Procedure (SOP) allows the preparation of formulations with appropriately sized and stable particles, and suitable rheological behavior in withdrawing the dose after stirring. Dose uniformity, expressed as mass and content variability, was determined using the criteria of the European and the United States Pharmacopoeia. Additionally, dose content variation of every mass determined was studied. A rational method was developed for determining the dose uniformity of UDCA in suspensions, whether freshly prepared or after storage under different conditions for 30 and 60 days. This method permits detection of differences between doses taken at different heights in the vessel at various times and storage conditions. UDCA was stable under all conditions studied, requiring the presence of glycerol in the formulation to obtain the declared API value after stirring. Storage of UDCA suspensions in a refrigerator increased variability between doses.

Liver disease in cystic fibrosis

The survival of patients with cystic fibrosis (CF) has progressively increased over recent decades, largely attributable to early diagnosis through newborn screening and advances in nutritional and respiratory care. As the life expectancy of patients with CF has improved, non-respiratory complications such as liver disease have become increasingly recognized. Biochemical derangements of liver enzymes in CF are common and may be attributed to a number of specific hepatobiliary abnormalities. Among them, Cystic Fibrosis-associated Liver Disease (CFLD) is clinically the most significant hepatic complication and is believed to have a significant impact on morbidity and mortality. However, there remains much conjecture about the extent of the adverse prognostic implications that a diagnosis of CFLD has on clinical outcomes. The purpose of this review is to give an overview of the current knowledge regarding liver disease in children with CF.

Ursodeoxycholic acid treatment in patients with cystic fibrosis at risk for liver disease

BACKGROUND

Meconium ileus has been detected as a risk factor for development of liver disease in cystic fibrosis, with influence on morbidity and mortality.

AIMS

To evaluate the effect of early treatment with ursodeoxycholic acid in patients with cystic fibrosis and meconium ileus to prevent chronic hepatic involvement and to explore the potential role of therapy on clinical outcomes.

METHODS

26 cystic fibrosis patients with meconium ileus (16 M, mean age 8,4 years, range 3,5-9) were assigned to two groups: group 1 (14 patients) treated early with ursodeoxycholic acid (UDCAe); group 2 (12 patients) treated with ursodeoxycholic acid at the onset of cystic fibrosis liver disease (UDCAd). Anthropometric data, pulmonary function tests, pancreatic status, complications such as diabetes, hepatic involvement and Pseudomonas aeruginosa colonisation were compared among groups.

RESULTS

A higher prevalence of cystic fibrosis chronic liver disease was observed in the UDCAd group with a statistically significant difference at 9 years of age (p<0.05). Chronic infection by P. aeruginosa was found in 7% of UDCAe and 33% of UDCAd (p<0.05). No differences were observed in nutritional status and other complications.

CONCLUSIONS

Early treatment with ursodeoxycholic acid may be beneficial in patients at risk of developing cystic fibrosis chronic liver disease such as those with meconium ileus. Multicentre studies should be encouraged to confirm these data.

Hepatobiliary disease in patients with cystic fibrosis

PURPOSE OF REVIEW

This review explores the recent advances in knowledge regarding hepatobiliary disease in patients with cystic fibrosis.

RECENT FINDINGS

Hepatobiliary abnormalities associated with cystic fibrosis are varied in nature and range from defects attributable to the underlying genetic defect to those related to systemic disease and malnutrition. Novel research into the underlying pathogenesis of cystic fibrosis liver disease and the primary role of cystic fibrosis transmembrane conductance regulator in biliary secretory epithelium is presented. This work has been fostered by the development of new animal models of cystic fibrosis transmembrane conductance regulator dysfunction. Of the wide range of hepatobiliary complications associated with cystic fibrosis the most clinically relevant problem is progression of focal biliary cirrhosis to multilobular cirrhosis with its attendant complications of portal hypertension and potentially end-stage liver disease. However, recent studies suggest that liver transplantation may not improve survival in patients with cystic fibrosis and significant portal hypertension.

SUMMARY

Hepatobiliary disease is a common finding in patients with cystic fibrosis; the pathogenesis is multifactorial in nature. As new therapeutic strategies emerge, life expectancy will continue to increase as will the impact of liver disease on quality of life and survival of patients with cystic fibrosis. This review will discuss novel insights into pathogenesis as well as diagnostic and management options.

The benign course of liver disease in adults with cystic fibrosis and the effect of ursodeoxycholic acid

BACKGROUND AND AIMS

The life expectancy of patients with cystic fibrosis (CF) has been increasing and the associated liver disease has emerged as a significant medical issue. Our aim was to describe the clinical features, course and effect of ursodeoxycholic acid (UDCA) on liver disease in an adult CF population.

STUDY

From 1983 to 2005, 278 patients with CF were followed up at the Alfred Hospital, an adult tertiary referral centre. Twenty-seven patients (9.7%) satisfied the criteria for liver disease and their clinico-pathological features were assessed. The effect of UDCA on hepatobiliary symptoms and biochemical parameters was determined.

RESULTS

The mean age at liver disease diagnosis was 23 years (range 8-47 years). Portal hypertension was present in 18 (67%) patients. During a median follow-up of 7 years (range 1.5-15), variceal haemorrhage occurred in two patients and ascites in three (one spontaneously). Nine (33%) patients died and five (19%) underwent lung transplantation. There was no encephalopathy, liver transplantation or liver-related deaths. UDCA was taken by 22 patients and was associated with a significant improvement in hepatobiliary symptoms [11/22 (50%) in the pre-UDCA period vs 1/22 (4%) in the post-UDCA period; P=0.0003] and a significant reduction in aspartate aminotransferase (P=0.005); alanine aminotransferase (P<0.001); gamma-glutamyltranspeptidase (P=0.021); and alkaline phosphatase (P<0.001).

CONCLUSIONS

Liver disease in adults with CF is commonly complicated by portal hypertension, but morbidity and mortality associated with this in our small patient population were low. UDCA is associated with improvement in hepatobiliary symptoms and liver function tests.

Cystic fibrosis: a review of epidemiology and pathobiology

Improvements in outcomes for patients who have cystic fibrosis (CF) have been striking in the last 30 years. Median survival now approaches the fifth decade of life. Advances in the understanding of the basic defect and the pathobiology of CF have led to new treatments, some of which have undoubtedly contributed to this success. Improved understanding of the basic defect and the acquisition and maintenance of epidemiologic resources for the CF population in the United States have allowed us to determine predictors of survival and identify genetic, environmental, and therapeutic factors that may influence it. This article reviews some of the key epidemiologic and pathobiologic factors discovered thus far.

Isolation and determination of bile acids

In this article, the methods of isolation and determination of bile acids are reviewed. Methods for separation of bile acids from cattle and pig bile are given in detail. Isolation of a mixture of cholic acid and deoxycholic acids from cattle bile and their subsequent purification are described. The isolation and purification of hyodeoxycholic acid and other components of pig bile are also included. Methods for the determination of bile acids in various biological samples are reviewed, including enzyme assays, radioimmunoassay, enzyme immunoassay and chromatographic methods. Among chromatographic methods, separation and determination of bile acids by thin-layer chromatography, gas chromatography and high performance liquid chromatography are reviewed. Particular attention is given to the use of high performance liquid chromatography since this has recently been the most commonly applied method for the separation and determination of bile acids.

Conjugation with taurine prevents side-chain desaturation of ursodeoxycholic and beta-muricholic acids in bile fistula rats

The metabolism of intravenously infused bile salts, tauroursodeoxycholate, tauro-beta-muricholate and their corresponding unconjugated forms in the liver was investigated in bile salt-depleted bile fistula rats. The biliary bile salt composition was determined by gas chromatography-mass spectrometry using chemical positive ionization and electron-impact methods. For an infusion rate of 2 micromol/min/kg, all bile salts were efficiently secreted in bile, inducing similar choleresis. Only tauroconjugated bile salts were recovered; no glucuronide or glyco derivatives were detected. The infusion of free ursodeoxycholate led to the appearance of a metabolite identified as a Delta22 derivative (12%). A similar biotransformation rate (11%) was observed following free beta-muricholate infusion. In contrast, no metabolite was observed after infusion of the tauroconjugated form of ursodeoxycholate and beta-muricholate. The unsaturation process probably depends on the availability of the carboxyl group for the starting step of the beta-oxidation mechanism. In conclusion, the current in vivo study demonstrates a hepatic origin for Delta22 bile salts. It also shows that free bile salts were sensitive to Delta22 formation while conjugation with taurine totally prevented the side-chain oxidation of the two 7beta-hydroxylated bile salts.

Parenteral nutrition-associated liver complications in children

Parenteral nutrition is a life-saving therapy for patients with intestinal failure. It may be associated with transient elevations of liver enzyme concentrations, which return to normal after parenteral nutrition is discontinued. Prolonged parenteral nutrition is associated with complications affecting the hepatobiliary system, such as cholelithiasis, cholestasis, and steatosis. The most common of these is parenteral nutrition-associated cholestasis (PNAC), which may occur in children and may progress to liver failure. The pathophysiology of PNAC is poorly understood, and the etiology is multifactorial. Risk factors include prematurity, long duration of parenteral nutrition, sepsis, lack of bowel motility, and short bowel syndrome. Possible etiologies include excessive caloric administration, parenteral nutrition components, and nutritional deficiencies. Several measures can be undertaken to prevent PNAC, such as avoiding overfeeding, providing a balanced source of energy, weaning parenteral nutrition, starting enteral feeding, and avoiding sepsis.

Long-term prospective study of the effect of ursodeoxycholic acid on cystic fibrosis-related liver disease

GOALS

To evaluate the efficacy of UDCA in arresting the progression of the early multifocal hepatic lesion to overt CF-related NBC.

BACKGROUND

Focal biliary cirrhosis is an early hepatic pathologic change related to the ion transport defect in cystic fibrosis. The factors involved in the progression of focal to nodular biliary cirrhosis are not clear. Ursodeoxycholic--a hydrophilic, nontoxic, choleretic, and hepatoprotective exogenous bile acid--has been reported to be effective in the management of cholestatic liver disease.

STUDY

For 10 years at 6-month intervals, 70 individuals with cystic fibrosis (38 men and 32 women; age range, 2--29 years) were examined using hepatosplenomegaly, liver function tests, and ultrasound liver scan. Patients demonstrating evidence of liver involvement at the onset or during the study received ursodeoxycholic acid 20 mg/kg body weight.

RESULTS

After the administration of ursodeoxycholic acid, the progression of nodular biliary cirrhosis ultrasound changes was arrested, hepatic function was preserved, and no variceal bleeding was observed. No case of focal biliary cirrhosis progressed to nodular biliary cirrhosis. Furthermore, the multifocal, multilobular changes suggestive of focal biliary cirrhosis on ultrasound scan were reversed to normal.

CONCLUSION

Ursodeoxycholic acid is effective in improving cholestasis and hepatic dysfunction in nodular biliary cirrhosis and, also, in reversing the early sonography findings suggestive of focal biliary cirrhosis. It is speculated that ursodeoxycholic acid may prove to affect the natural history of cystic fibrosis-related liver disease.

Use of ursodeoxycholic acid in liver diseases

Ursodeoxycholic acid is currently the only established drug for the treatment of chronic cholestatic liver diseases. It has cytoprotective, anti-apoptotic, membrane stabilizing, anti-oxidative and immunomodulatory effects. Prolonged administration of ursodeoxycholic acid in patients with primary biliary cirrhosis (PBC) is associated with survival benefit and a delaying of liver transplantation. There is evidence that it might even prevent progression of the histologic stage of PBC. It also has a beneficial effect on primary sclerosing cholangitis, intrahepatic cholestasis of pregnancy, liver disease associated with cystic fibrosis, chronic graft versus host disease, total parenteral nutrition associated cholestasis and various pediatric cholestatic liver diseases. In the present review the current knowledge about the mechanisms of the action and role of ursodeoxycholic acid in the treatment of various liver diseases has been discussed.

Newer therapies for cystic fibrosis

Cystic fibrosis (CF) is a chronic, progressive, genetic disease caused by flawed ion transport across epithelial membranes due to a genetic mutation. Most therapeutic efforts are centred on the main clinical manifestations of the disease: progressive destructive airway disease and pancreatic insufficiency. Most individuals with CF succumb to lung disease. The present-day therapeutic armamentarium includes agents that have been used for many decades, some of which have experienced transformations in their formulation or mode of administration thanks to the introduction of new manufacturing technologies. The development of new therapies involves new conceptual approaches, based on recent understanding of the disease. These therapies await proof of concept or clinical experimentation before being accepted as useful means to arrest the progression of the disease. In this article we will review therapeutic agents introduced into the clinical arsenal in the last 20 years, as well as experimental therapies under active investigation.

Delayed intestinal visualization at hepatobiliary scintigraphy is associated with response to long-term treatment with ursodeoxycholic acid in patients with cystic fibrosis-associated liver disease

BACKGROUND/AIMS

Abnormalities of biliary drainage have been documented at hepatobiliary scintigraphy in many but not all patients studied with cystic fibrosis-associated liver disease. Ursodeoxycholic acid was shown to be beneficial in this disease, mainly by improving biliary secretion. Therefore, patients with impaired biliary drainage are expected to obtain the greatest benefit from this treatment.

METHODS

We evaluated the effects of long-term treatment with ursodeoxycholic acid in 36 patients with cystic fibrosis-associated liver disease, and compared the response in patients presenting a normal (n=18) or delayed time of intestinal visualization (n=18) at baseline hepatobiliary scintigraphy.

RESULTS

The mean treatment duration was 58+/-26 (S.D.) months and 63+/-29 months in the groups with normal or delayed time of intestinal visualization, respectively. The time of intestinal visualization decreased (57+/-23%, p<0.001) from baseline in patients with initially abnormal values and became normal in four (22%). Treatment failure, i.e. lack of sustained normalization of serum liver enzymes or the occurrence of a clinically relevant adverse event, was more frequently observed in patients with a normal time of intestinal visualization at baseline (OR, 5.50; 95% CI, 1.32-22.7). When only clinically relevant adverse events were considered, they occurred in six of the latter patients (liver transplantation in one case, development of ultrasographic or endoscopic signs of portal hypertension in six cases), but in only one patient (development of portal hypertension) in the group with delayed time of intestinal visualization (OR, 10.82; 95% CI, 1.17-100.4).

CONCLUSIONS

Delayed intestinal visualization at hepatobiliary scintigraphy in patients with cystic fibrosis-associated liver disease seems to predict a better response to ursodeoxycholic acid.

The evolution of liver disease in cystic fibrosis

OBJECTIVES

To describe prospectively the evolution of liver abnormalities in cystic fibrosis (CF), and to assess their impact on nutritional status.

STUDY DESIGN

124 children (61 boys) with CF (median age, 5.4 years; range, 0.1-13.9) were followed longitudinally for a median of four years. Annual clinical examination, biochemistry, and ultrasound assessment were performed. Chrispin-Norman score, anthropometry, and bacterial colonisation of airway secretions were measured at each assessment.

RESULTS

At initial assessment, 45% of the patients had no liver abnormalities, 42% had biochemical abnormality, 35% ultrasound abnormality, and 6% had clinical abnormality of the liver. In this cross sectional analysis, abnormal biochemistry was present in 40% of children with ultrasound or clinical abnormalities, but when longitudinal follow up data were analysed, abnormal biochemistry preceded or coincided with abnormal ultrasound or clinical hepatosplenomegaly in three quarters of 53 children developing new abnormalities. Eighty four of 124 children (68%) showed ultrasound or clinical evidence of liver abnormality at some point during the four years of follow up. No association was found between liver disease and nutritional status.

CONCLUSIONS

Hepatic abnormality was common in this group of children with CF, was often predicted by intermittent biochemical abnormalities, and was not associated with deterioration in nutritional status.

Parenteral nutrition-associated cholestasis in preterm neonates: evaluation of ursodeoxycholic acid treatment

BACKGROUND/OBJECTIVE

Parenteral nutrition is an integral part of the care of premature infants. Cholestatic liver disease is a frequent complication of prolonged parenteral nutrition, especially in premature infants. It has been suggested that ursodeoxycholic acid may alter the course of parenteral nutrition-associated cholestasis in children and adults. We attempted to determine the efficacy of ursodeoxycholic acid in premature infants with parenteral nutrition-associated cholestasis.

METHODS

Retrospective chart review of all infants receiving ursodeoxycholic acid for parenteral nutrition-associated cholestasis in a 40 bed neonatal intensive care unit. Efficacy of ursodeoxycholic acid was evaluated by response of bilirubin, alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase over a treatment period of at least 1 month.

RESULTS

Six infants with parenteral nutrition-associated cholestasis who had received ursodeoxycholic acid for one month were identified. Doses of ursodeoxycholic acid ranged from 15-30 mg/kg/day. Cholestasis appeared at a mean age of 47 +/- 17 (mean +/- SD) days after a mean of 42 +/- 15 days of parenteral nutrition. Transaminase levels decreased in three, and either increased or did not change in the other three infants. Bilirubin levels decreased in all infants. Alkaline phosphatase showed a non significant trend to decreased levels. Consistent improvement in all infants was noted only after 10 days of full enteral nutrition. No toxicity was found during ursodeoxycholic acid treatment.

CONCLUSIONS

Ursodeoxycholic acid treatment in premature infants appears to be safe, and leads to an early sustained decrease in bilirubin levels by two weeks of therapy. The response of transaminase levels was not sustained in our small cohort.

Bile acid abnormalities in cholestatic liver diseases

There is ample reason to believe that UDCA is the drug of choice in cholestatic liver diseases. It is possible that UDCA has to be administered for prolonged periods to see appreciable reversal in liver damage. Nevertheless, the amelioration of symptoms and improvement in nutrition of patients are equally important. Disabling symptoms such as pruritus are often brought under control, and quality of life improves. Clearly the goal for UDCA therapy is to slow the rate of disease progression, lessen the mortality risk, and improve the quality of life in patients. It is possible that a combination therapy would be more beneficial than UDCA alone. Initial results of administering UDCA with colchicine have shown no improvement in liver histology; however, administration of UDCA together with a strong anti-inflammatory drugs may be helpful to halt immune destruction of liver cells.

Ursodeoxycholate alleviates alcoholic fatty liver damage in rats

The hydrophilic bile salt ursodeoxycholate (UDC) improves cholestasis in several liver diseases and is in vitro an efficient membrane stabilizer. However, its action on chronic ethanol-induced liver damage is not established. We thus sought to determine the effect of UDC on chronic ethanol-induced steatosis and on liver plasma membrane fluidity in rats. Male rats were pair-fed liquid diets containing 36% of calories as ethanol (alcohol diet) or an isocaloric maltose-dextrin mixture (control diet). Four groups of 10 animals received, respectively, during 30 days: the control diet, the control diet + UDC (90 mg/kg/day), the alcohol diet, and the alcohol diet + UDC. Bile was collected for assessment of bile flow, biliary lipids, and individual bile salts. Liver lipid contents and lipid peroxidation were determined. Plasma membrane fluidity was assessed by fluorescence polarization of various probes. Alcohol treatment caused a 4-fold increase in liver triacylglycerol and cholesterol ester levels. UDC supplementation significantly reduced these increases by 50% and 40%, respectively. UDC intake was associated with a marked decrease in alcohol-induced lipid peroxidation. Bile flow, bile salt, and phospholipid secretion were slightly increased by alcohol intake. The addition of UDC-enriched bile with tauroursodeoxycholate (38%) without significantly affecting the biliary parameters. Lastly, UDC treatment almost totally prevented the 20% increase in liver plasma membrane fluidity due to chronic alcohol intake. This study shows that UDC intake, concomitant with alcohol diet, exerts a clear-cut membrane protective effect that might alleviate ethanol-induced lipid disorders.

Clinical and genetic risk factors for cystic fibrosis-related liver disease

OBJECTIVE

The aim of this study was to define the role of possible risk factors for the development of cystic fibrosis (CF)-related liver disease and to analyze the association between liver disease and the different genotypes present in the Israeli CF patient population.

PATIENTS AND METHODS

All patients followed at the seven CF centers in Israel were included in this study. Liver disease was determined by persistently elevated serum liver enzymes and/or bilirubin, and/or significant ultrasonographic changes suggestive of chronic liver disease. The following clinical parameters were evaluated: ethnic origin, age at assessment of liver function, sex, history of meconium ileus, pancreatic function, history of distal intestinal obstruction syndrome, pulmonary function, and cystic fibrosis transmembrane conductance regulator mutation analysis.

RESULTS

Of the 288 patients screened, 80 (28%) had liver disease. Of the 256 patients with pancreatic insufficiency, 80 (31%) had liver disease compared with none of the 32 patients with pancreatic sufficiency. Genotype-phenotype correlation was performed on 207 patients carrying identified mutations that were previously classified according to phenotype severity. Liver disease was found in 56 (32%) of 173 patients carrying mutations associated with a severe phenotype and in 6 (38%) of 16 patients carrying at least one mutation associated with a variable genotype (G85E and/or 5T allele). None of the 18 patients carrying the 3849+10kb C->T mutation had liver disease. Prevalence of liver disease increased with age. No correlation was found between liver disease and severity of lung disease, nutritional status, history of meconium ileus, or distal intestinal obstruction syndrome.

CONCLUSION

CF patients who have pancreatic insufficiency and carry mutations associated with a severe or a variable genotype are at increased risk to develop liver disease.

A two-year prospective study of the effect of ursodeoxycholic acid on urinary bile acid excretion and liver morphology in cystic fibrosis-associated liver disease

The efficacy of 2 years of treatment with ursodeoxycholic acid (UDCA) in cystic fibrosis (CF)-associated liver disease was evaluated by liver biopsies and liver function tests in 10 patients aged 8 to 28 years. The metabolism of UDCA was investigated by analysis of urinary bile acids with fast atom bombardment mass spectrometry (FABMS) and gas-liquid chromatography-mass spectrometry. Eight patients responded with normalization of liver function tests (LFT) and all with decreased serum levels of immunoglobulin G (IgG). Blind evaluation of liver biopsies indicated improved liver morphology with less inflammation and/or bile duct proliferation than before treatment with UDCA in 7 patients. Only 1 patient had signs of progression of clinical liver disease. The proportion of UDCA and isoUDCA in urine varied, but increased during treatment from a mean (median) of approximately 4% (3%) to 40% (40%) of total bile acids. The increase was not related to LFT. The secondary bile acids, such as lithocholic acid (LCA) and deoxycholic acid (DCA), did not increase significantly. The excretion pattern of glycosidic conjugates of UDCA and its metabolites was similar to that found in healthy individuals, UDCA and isoUDCA being mainly excreted in conjugation with N-acetylglucosamine. This study shows that UDCA modulates inflammation in CF-associated liver disease and indicates improvement of liver morphology during 2 years of treatment.

Effect of ursodeoxycholic acid therapy on hepatic function in children with intrahepatic cholestatic liver disease

BACKGROUND

Ursodeoxycholic acid (UDCA) has been shown to improve pruritus, alanine aminotransferase (ALT), and cholesterol levels in children with intrahepatic cholestatic liver disease. However, the effect of UDCA on quantitative tests of hepatic function in children is uncertain.

METHODS

A 2.5-year, open label, crossover study, was designed to determine the effect of UDCA (15-20 mg/kg per day for 12 months, off for 6 months, and on again for 12 months) on clinical symptoms, biochemical test results, galactose and caffeine elimination half-lives (t1/2), and quantitative hepatic scintigraphy in 13 subjects aged 13.1 +/- 2.1 years (10 of whom completed the entire study), with intrahepatic cholestasis.

RESULTS

Pruritus improved with UDCA in the 6 patients with pruritus on entry into the study. At 12 months, there was a significant decline in ALT, gamma-glutamyl transpeptidase, and plasma levels of copper and manganese, with no further decline in these levels at 24 months. There were no changes in bilirubin or cholylglycine levels. After therapy was discontinued at 12 months, UDCA was restarted within 1 month in 9 of 12 patients in response to a doubling of ALT (n = 6) or worsening pruritus (n = 3). Galactose t1/2 increased after 12 months, with no further increases after 24 months of UDCA therapy, whereas caffeine t1/2 did not change. There were no significant changes in hepatic scintigraphy throughout the study.

CONCLUSIONS

These data suggest that although UDCA therapy improves pruritus and results in a reduction in ALT and gamma-glutamyl transpeptidase, UDCA therapy did not improve quantitative measures of hepatic function in children with intrahepatic cholestasis.

Ursodeoxycholic acid improves cholestasis in infants with cystic fibrosis

OBJECTIVE

To describe two infants with cholestatic jaundice treated with ursodeoxycholic acid (UDCA).

CASE SUMMARY

Two infants with cystic fibrosis (CF)-associated hepatobiliary disease, manifesting as cholestatic jaundice and elevated liver enzymes within the first 6 weeks of life, had improved biochemical indices of liver function following treatment with UDCA 20-40 mg/kg/d.

DISCUSSION

To our knowledge, this is the first report of UDCA treatment in infants with CF-associated cholestatic jaundice. Infants and children require treatment with increased doses of UDCA to compensate for reduced intestinal absorption of bile acid and immaturity of the enterohepatic circulation.

CONCLUSIONS

UDCA appears to be a cost-effective treatment for CF-associated hepatobiliary disease in infants and children.

Low-dose versus high-dose ursodeoxycholic acid in cystic fibrosis-related cholestatic liver disease. Results of a randomized study with 1-year follow-up

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 randomized 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.

Biliary obstruction in infants with cystic fibrosis requiring Kasai portoenterostomy

Cystic fibrosis is associated with an inspissated bile syndrome producing cholestasis secondary to plugging of macroscopically normal bile ducts. In extreme neonatal forms, with early profound intrahepatic cholestasis, the process can be associated with a marked decrease in ductal diameter, varying from hypoplasia to atresia. From 1990 to 1995 three infants were identified with cystic fibrosis, persistent jaundice, and complete absence of biliary excretion despite expectant and conservative treatment including choleretics and surgical biliary irrigation. Abdominal ultrasounds showed contracted gallbladders and no evidence of dilated ducts. Liver biopsy results in two infants showed portal fibrosis, paucity of bile ducts, and minimal inflammation. The third infant had moderate inflammation, bile duct replication, and plugging. Two infants had undergone intestinal resection followed by hyperalimenation for complications of meconium ileus in the newborn period. Surgical exploration was undertaken at 7 to 12 weeks of age. Gross findings were typical of biliary atresia with microgallbladders and nonpatency of the cystic duct. Cholangiograms failed to document ductal patency in two patients who were then treated with a Kasai portoenterostomy. The third infant had patent hypoplastic ducts and underwent only biliary irrigation. Although bile flow was transiently achieved, jaundice recurred, and at reexploration at 16 weeks of age a Kasai poroenterostomy was performed. Histological review of the biliary specimens showed microscopically patent ducts in two patients and proximal patency and distal atresia in the third. All the ducts had mural fibrosis with cystic changes. Bile drainage was achieved in each instance, although in one patient with hypoplastic ducts scant output of highly concentrated bile proved insufficient to arrest progressive liver failure. The subsequent two patients responded with resolution of hyperbilirubinemia and normalization of liver function. They remain free of biliary complications at 30 and 40 months postoperatively. This manifestation of cystic fibrosis in infants is suggested by prolonged jaundice unresponsive to choleretics, nondilated bile ducts and gallbladder on ultrasound, absent biliary excretion on nuclear scan, and characteristic liver biopsy. Exploration is warranted, and discovery of atrophic bile ducts may be best managed with reconstruction.

Ursodeoxycholic acid improves the hepatic metabolism of essential fatty acids and retinol in children with cystic fibrosis

OBJECTIVE

Several clinical trials of ursodeoxycholic acid (UDCA) have shown improvement of liver-function test results in cystic fibrosis (CF) with liver disease; however, there is no evidence that the long-term course will be affected. In view of the observations that UDCA can change the lipid profile and that patients with CF and liver disease are more likely to have essential fatty acid (EFA) deficiency, we elected to examine changes in the lipid profile and in the status of fat-soluble vitamins in response to UDCA.

METHODS

Nineteen children with CF and liver dysfunction were recruited for a double-blind, crossover study of 1 year's duration, followed by treatment of the entire group. UDCA was administered at a dosage of 15 mg/kg per day, which, in the absence of a 50% decrease of alanine transaminase or aspartate transaminase or both within 2 months, was increased to 30 mg/kg per day.

RESULTS

At entry, all patients had biochemical evidence of EFA deficiency. The lipid profiles during an average period of 25 months of follow-up showed a significant decrease in triglycerides (p <0.002), cholesterol (p <0.02), and total fatty acids (p <0.006). In addition, UDCA therapy led to an improvement in EFA status, as indicated by an increase (p <0.05) in the n-6 fatty acid concentration and a reduction (p <0.04) in the 20:3n-9/20:4n-6 fatty acid ratio. Although no change in vitamin E levels was observed, retinol metabolism was altered. There was an increase (p <0.02) in the unesterified retinol/retinol binding protein molar ratio in the absence of a difference in retinol binding protein concentration. Furthermore, retinyl esters, which normally account for less than 3% of circulating retinol, decreased (p <0.05) from 13.7% +/- 3.6% to 8.1% +/- 1.7%.

CONCLUSIONS

This study confirms that UDCA alters lipoprotein metabolism and shows that it improves the EFA and retinol status of patients with CF and liver disease.

Ursodeoxycholate improves hepatobiliary dysfunction induced by valproate-carbamazepine treatment in the rat

Carbamazepine (CBZ) and valproate (VPA) are commonly used antiepileptic drugs. These drugs, either alone or combined, may produce hepatotoxicity. We report results of a biochemical and histological study of the liver in rats treated for eight days with VPA (500 mg/Kg/day), CBZ (200 mg/Kg/day) and VPA plus CBZ. A hepatoprotective bile salt, ursodeoxycholate (UDC, 60 mg/Kg/day) was given as a supplement to rats treated with the VPA+CBZ combination. VPA strongly modified the biliary biochemical parameters inducing hypercholeresis and hyposecretion of phospholipids. Microscopically, hepatocytes showed intense vacuolation of the peripheral cytoplasm and alterations of the mitochondrial matrix. CBZ produced increased choleresis but had no effect on biliary lipid parameters. Ultrastructurally, CBZ induced marked proliferation of the smooth endoplasmic reticulum of hepatocytes. The VPA+CBZ association produced a combination of the alterations induced independently by each drug. In both bile and plasma, increased CBZ-epoxide and decreased VPA levels were observed. The addition of UDC restored the biliary phospholipid secretion, decreased cytoplasmic vacuoles and mitochondrial alterations, and diminished the hypertrophy of smooth endoplasmic reticulum, indicating a clear beneficial effect of UDC on hepatobiliary dysfunction induced by the VPA+CBZ combination. Furthermore, the supplementation with UDC did not significantly change the plasma levels of the antiepileptic drugs.

Antioxidants in pediatric gastrointestinal disease

Oxidant stress seems to be involved in the pathogenesis of several important gastroenterologic disorders in infants and children. The question can still be asked, in most circumstances, whether the oxidant stress precedes, and therefore is involved in, tissue or cellular injury or is a result of injury and not of clinical importance. The data favor the former situation in several inflammatory conditions of the bowel and in a variety of liver diseases. Experimental and clinical testing of this possible basic mechanism of tissue injury over the next few years will shed light on the role of antioxidants in treating gastrointestinal disorders.

[Bile acids and their therapeutic use in children]

Bile acids are natural detergents and the end-products of cholesterol metabolism. Their functions are mostly digestive: induction of bile flow and solubilization of biliary and alimentary lipids. They circulate along the enterohepatic cycle, and probably also along a shorter route, the cholehepatic shunt. They are relatively hydrophobic and perpetuate or worsen the hepatic lesions when their excretion is impaired in cholestasis, because of their affinity for biological membranes. Their functions depend on their relative hydrophilicity and ionization, ie on their structure and state of conjugation. They have an immunosuppressive effect in vivo and in vitro. Ursodeoxycholic acid (UDC) is a hydrophilic bile acid used in chronic cholestatic diseases. Biological improvement has been proven in autoimmune cholangiopathies in adults, and cystic fibrosis-associated liver disease in children. Clinical studies are on the way for other indications. It is still too early to evaluate the long-term clinical benefits, eg the reduction in needs for liver transplantation. UDC acid may induce a bicarbonate-rich hypercholeresis through the cholehepatic shunt, that would explain its efficacy in cystic fibrosis. In disorders of bile acid synthesis or transport, it could shunt the enzymatic block, or reestablish the bile flow through its osmotic effect. Like other bile acids it interacts with membranes, and is thought to stabilize them. In chronic cholestasis it would protect the membranes against the adverse effect of non-excreted endogenous bile acids. This interaction can also explain its immunosuppressive effect, through non-specific inhibition of transmission at the cell surface. That would explain the preferential clinical efficacy of UDC in autoimmune cholestasis, and stimulate its evaluation in "immunological" indications, such as liver transplantation and hepatic graft versus host disease.

Serum glutathione S-transferase B1 activity as an index of liver function in cystic fibrosis

AIMS

To evaluate serum glutathione S-transferase B1 (GST B1), a highly sensitive test of hepatocellular function, as a means of identifying liver disease in patients with cystic fibrosis (CF).

METHODS

The presence of liver disease was sought over a three year period in 60 children with CF, using a combination of clinical assessment, ultrasound examination, conventional biochemical tests of liver function (LFTs), and measurement of GST B1.

RESULTS

Reference ranges for serum GST B1 were established in a paediatric control population. The 95% value (4.55 micrograms/l) was similar to the upper limit of normal previously derived in adults. Mean (SE) serum GST B1 activities were higher in the CF population (9.0 (1.14) micrograms/l) than in age matched controls (2.4 (0.15) micrograms/l). Ten patients with CF showed clinical signs of liver dysfunction. All but one had a serum GST B1 > 4.55 micrograms/l. Twelve other patients had elevated LFTs without clinically evident liver dysfunction, six had abnormal ultrasound scans and two showed both of these anomalies. Thirty patients with CF had neither biochemical, ultrasonographic nor clinical signs of liver disease. On review three years later, clinically important liver disease was reaffirmed in eight of the 10 index cases and had become apparent in a further eight, all of whom had elevated GST B1 activities. Five (36%) of the patients with elevated LFTs and two (33%) with isolated ultrasound changes continued to show these abnormalities.

CONCLUSIONS

The limitations of conventional LFTs and ultrasound scans were evident from this study. The results suggest that elevated GST B1 activities may be a better predictor of hepatic dysfunction in CF than conventional LFTs.

Improvement of cyclosporin A-induced cholestasis by tauroursodeoxycholate in a long-term study in the rat

Cyclosporin A is an essential immunosuppressive drug, but it is potentially toxic to the kidney and liver. Ursodeoxycholic acid, a hydrophilic bile acid, has been reported to improve cholestasis in liver disease in man. The purpose of this work was to examine whether tauroursodeoxycholate could reduce cyclosporin A-induced hepatic or renal injuries in the rat. After randomization into three groups (N = 8), rats received daily for 17 days: cyclosporin A intraperitoneally alone (30 mg/kg) or cyclosporin A intraperitoneally and tauroursodeoxycholate (60 mg/kg) by gavage; control received the cyclosporin A excipient. Under tauroursodeoxycholate, cholestatic parameters (bile flow, bile salt secretion, serum bile salts, serum bilirubin) improved significantly without affecting cyclosporin A blood levels, and excretion of the drug and its metabolites in bile increased by 47%. Serum creatinine levels were better preserved, although not significantly. These results show that tauroursodeoxycholate prevents cyclosporin A-induced cholestasis in long-term treatment in rats, possibly by facilitating the drug elimination in bile.

Analysis of risk factors for the development of liver disease associated with cystic fibrosis

We prospectively screened for liver disease patients with cystic fibrosis who were more than 3 years of age and who were followed at the cystic fibrosis center of the University of Milan. From January 1991 to December 1992, we screened 189 patients; clinical, biochemical, and echographic abnormalities suggestive of overt liver disease were present in 34 (18%). To define risk factors for the development of liver disease associated with cystic fibrosis, we evaluated the possible role of specific mutations of the CFTR (cystic fibrosis transmembrane regulator) gene and of different clinical and demographic characteristics (sex, pancreatic status, meconium ileus or its equivalent) through a comparison of patients with cystic fibrosis and overt liver disease (n = 34) and those without liver disease (n = 155). Genetic analysis failed to reveal any significant difference in the allele frequencies of defined (delta F508, 1717-1G-A, G542X, N1303K, W1282X, R553X) and undefined mutations of the CFTR gene in the two groups of patients; genotype frequencies were also not significantly different. Pancreatic insufficiency was present in all patients with liver disease and in 87.3% of those without liver disease. A male predominance was found in the group with liver disease. The frequency of meconium ileus or its equivalent was significantly higher in patients with cystic fibrosis and liver disease (35.3%) than in patients without liver disease (12.3%) (p = 0.0025). In the 31 patients with a history of meconium ileus or its equivalent, the following hepatic abnormalities occurred more frequently than in the 155 patients with cystic fibrosis who did not have meconium ileus: hepatomegaly, biochemical abnormalities, heterogeneous echographic pattern of the liver, and microgallbladder. Twenty-four patients with a history of meconium ileus or its equivalent underwent hepatobiliary scintigraphy (with technetium-labeled iminodiacetic acid derivatives), which showed morphologic abnormalities suggestive of impaired biliary drainage in 21 patients and abnormalities in function in 11. The risk of acquiring liver disease was increased almost fourfold in patients with a history of meconium ileus or its equivalent, in comparison with patients who had cystic fibrosis but were unaffected by these complications (odds ratio, 3.9043; 95% confidence interval, 1.666 to 9.149). We conclude that patients with cystic fibrosis and meconium ileus or its equivalent may benefit from prophylactic treatment with ursodeoxycholic acid; genetic analysis of the major mutations present in this population failed to provide evidence of the existence of a specific genetic marker for the development of liver disease in patients with cystic fibrosis.

Cystic fibrosis. Is treatment with ursodeoxycholic acid of value?

Liver and biliary diseases are common complications in cystic fibrosis (CF) and may even be so severe that liver transplantation is indicated in cases with mild pulmonary disease. The most common complications are steatosis, fibrosis/cirrhosis, micro gallbladder, cholelithiasis, and sclerosing cholangitis. Ursodeoxycholic acid (UDCA) has been used in the treatment of gallstones and pathological liver function in CF. The effect on gallstones has been contradictory, and the effect on liver function tests has been shown to be dose-dependent. A significantly better effect has been shown on liver function tests during treatment over 1 year with doses of 15-20 mg/kg/day. Although supplementation with taurine did not further improve this effect, it has been used in many studies. The biliary bile acid pool was enriched by UDCA from about 10% to 35-40%, but a similar increase was not seen in serum. We have studied the long-term effect of UDCA in 10 patients with liver fibrosis or cirrhosis and/or sclerosing cholangitis. Liver function and liver morphology examined on liver biopsies by both light and transmission electron microscopy (TEM) were followed for 2 years. Preliminary results of this study are encouraging. UDCA is an interesting drug which binds to the hepatocyte membranes, stabilizing membrane structure in in vitro experiments and increasing the bicarbonate excretion in bile in pigs. The mechanism of the effect of UDCA in CF might not only be an increased choleresis; further studies will focus on these aspects.

Failure of ursodeoxycholic acid to dissolve radiolucent gallstones in patients with cystic fibrosis

Ursodeoxycholic acid has been used widely to dissolve cholesterol gallstones and more recently was shown to improve clinical symptoms and biochemical indices in different chronic liver diseases, including that associated with cystic fibrosis. We treated 10 cystic fibrosis patients (5 males, 5 females, age range 2-22 years) with pancreatic insufficiency and normal liver function with ursodeoxycholic acid 15-20 mg/kg/day. Seven patients had radiolucent gallstones (in 3 cases associated with biliary sludge) and 3 had sludge; all were asymptomatic. Before treatment, the gallbladder was well opacified in oral cholecystogram. The gallbladder was scanned by ultrasound in similar conditions and by the same operator before administration of ursodeoxycholic acid and after a median period of treatment of 16 months (range 11-32 months). During treatment, all patients remained asymptomatic and the relative proportion of ursodeoxycholic acid in duodenal bile increased from 4.7 +/- 3.2% at baseline to 34.7 +/- 8.6%. Complete or partial dissolution of gallstones was never observed and the maximum diameter of stones increased from a mean of 6.1 +/- 3.4 to 8.0 +/- 5.3 mm; in one case the development of biliary sludge occurred during bile acid therapy. Sludge disappeared in 1 of the 6 patients who initially had it, while in 2 cases its volume increased. We conclude that ursodeoxycholic acid is not effective in most CF patients with gallstones, probably because cholesterol is not the main component of stone or sludge.