A preliminary trial of high-dose ursodeoxycholic acid in primary sclerosing cholangitis

BACKGROUND & AIMS: Ursodeoxycholic acid (UDCA) is used for the treatment of cholestatic liver diseases including primary biliary cirrhosis (PBC) for which it has a positive effect on laboratory values, may delay the development of liver failure and prolong the transplant-free disease period. Standard doses of UDCA (8-15 mg/kg daily) have been shown to be ineffective in the treatment of primary sclerosing cholangitis (PSC). We report on the findings (clinical, biochemical, histological, and cholangiographic) and side effects of a 2-year double-blind placebo-controlled preliminary study of high-dose UDCA in PSC patients. METHODS: Twenty-six patients with PSC were randomized to high-dose (20 mg/kg daily) UDCA or placebo. Cholangiography and liver biopsy were performed at entry and after 2 years. Symptoms, clinical signs, and liver biochemical tests were recorded at 3 monthly intervals. RESULTS: High-dose UDCA did not influence symptoms, but there was a significant improvement in liver biochemistry (serum alkaline phosphatase, P = 0.03; gamma-glutamyl transferase, P = 0.01) and a significant reduction in progression in cholangiographic appearances (P = 0.015) and liver fibrosis as assessed by disease staging (P = 0.05). In the treatment group, a significant increase in total bile acids and saturation with UDCA >70% confirmed patient compliance. No significant side effects were reported. CONCLUSIONS: High-dose UDCA may be of clinical benefit in PSC, but trials with a larger number of participants and of longer duration are required to establish whether the effect of high-dose UDCA on liver biochemistry, histology, and cholangiography in patients with PSC is translated into improved long-term survival.     

Latest and Emerging Therapies for Primary Biliary Cirrhosis and Primary Sclerosing Cholangitis

Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are the two most common causes of chronic cholestatic liver disease in adults. In PBC, therapy with ursodeoxycholic acid (UDCA) is safe and has been associated with tangible biochemical, histologic, and survival benefits. However, a need for different or adjuvant therapies remains for specific subsets of PBC patients, including those who do not respond to UDCA and those who have advanced histologic disease at presentation. Similarly, beneficial therapies for disease-related symptoms that do not typically respond to UDCA (eg, fatigue and pruritus) are still needed. In contrast to PBC, no medical therapy of proven benefit has been identified for patients with PSC. In PBC and PSC, adequate management of complications of chronic cholestasis is important. For both diseases, liver transplantation is the only curative option.     

Efficacy of colchicine in patients with primary biliary cirrhosis poorly responsive to ursodiol and methotrexate

OBJECTIVE: Approximately 20-30% of patients with primary biliary cirrhosis (PBC) respond fully to treatment with ursodeoxycholic acid (UDCA). The rest have progressive disease and eventually develop cirrhosis and liver failure. More effective treatment is needed. Methotrexate improved biochemical tests of liver function and liver histology in patients with PBC who had failed to respond to UDCA in one report and induced sustained biochemical and histological remission in another. The role of colchicine in PBC is unclear. We describe three patients with symptomatic PBC who responded very well to the addition of colchicine after they had failed to respond to UDCA alone and in combination with methotrexate. We suggest that colchicine should be tried in PBC patients who clearly fail to respond to UDCA. METHODS: Three patients with symptomatic biopsy-proven, antimitochondrial antibody-positive PBC failed to respond to UDCA and then to the addition of methotrexate. Colchicine was eventually added to the regimen. Symptoms, biochemical tests of liver function, and percutaneous liver biopsies were done at baseline, after treatment with UDCA, UDCA plus methotrexate, and UDCA plus methotrexate plus colchicine. RESULTS: All three patients responded after colchicine was added to UDCA and methotrexate. Symptoms, biochemical tests of liver function, and liver histology improved in all, and blood tests normalized in two. CONCLUSIONS: Colchicine may be effective treatment in some symptomatic patients with PBC who respond incompletely to UDCA alone or in combination with methotrexate. Colchicine may be tried in such patients.     

Treatment of primary biliary cirrhosis.

Although primary biliary cirrhosis (PBC) is generally a progressive disease, the rate of progression varies greatly from one patient to another. The terminal phase is characterized by hyperbilirubinaemia (>100 micromol/l), a major decrease in the number of intrahepatic bile ducts, and extensive fibrosis or cirrhosis. It is now well established that orthotopic liver transplantation is the treatment of choice for patients entering the terminal phase of the disease.A variety of therapeutic agents have been proposed for treatment of patients with PBC. However, most have been found ineffective or too toxic to be widely used. In contrast, there is accumulating evidence from large therapeutic trials that long-term administration of ursodeoxycholic acid (UDCA) is safe and prolongs survival free of liver transplantation. Treatment with UDCA slows the histological progression and delays the onset of cirrhosis.In patients who have a sub-optimal response to UDCA therapy alone, the combination of colchicine or methotrexate with UDCA has minimal or no additional benefit, whereas that with corticosteroids is more promising but not yet demonstrated.Among causes of non-response to UDCA therapy, the most common is the PBC-autoimmune hepatitis overlap syndrome. The benefit from the combination of corticosteroids and UDCA in this setting is obvious.Further studies are needed to define the patients who are most likely to respond to UDCA therapy and to assess the benefit of combined medical treatments.     

Alterations in tight junctions differ between primary biliary cirrhosis and primary sclerosing cholangitis

Tight junctions (TJ) of biliary epithelial cells (BEC) and hepatocytes prevent bile regurgitation from the biliary tract. Alterations in these TJs may participate in chronic cholestatic liver diseases such as primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). We examined the localization of 2 TJ proteins, ZO-1 and 7H6, in these diseases. Frozen sections from livers of PBC, PSC, extrahepatic cholestasis (Ex-C), and hepatitis C-associated cirrhosis (LC-C), as well as histologically normal livers, were processed for double-fluorescence immunohistochemistry. In controls and cirrhosis, 7H6 and ZO-1 colocalized surrounding the luminal space of the bile ducts and outlined the bile canalicular spaces between hepatocytes. In untreated PBC, immunostaining for ZO-1 in BEC of bile ducts 40 to 80 microm in diameter was preserved, but that for 7H6 was diminished to absent. In PBC treated with ursodeoxycholic acid (UDCA), immunostaining for 7H6 was well preserved. In PSC as well as in Ex-C, immunostaining for both 7H6 and ZO-1 was well preserved in bile ducts. In hepatocytes, ZO-1 showed preserved immunoreactivity, but immunostaining for 7H6 frequently disappeared. The percentage of bile ducts with immunostaining for 7H6 in all bile ducts with immunostaining for ZO-1 was significantly reduced in PBC compared with that in control, LC-C, Ex-C, and PSC (all P <.0001). Substantial alteration in the TJ protein occurs predominantly in bile ducts in PBC and in hepatocytes in PSC, suggesting increased paracellular permeability along different paracellular routes for bile regurgitation in these chronic cholestatic liver diseases.     

Treatment options for primary biliary cirrhosis and primary sclerosing cholangitis

Opinion statement Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are chronic cholestatic liver diseases that affect 0.5 to 40 per 100,000 and 1 to 6 per 100,000 Americans, respectively. Prompt recognition and management of the clinical manifestations of these diseases is essential for the patients’ well-being and ultimate outcome. Ursodeoxycholic acid (UDCA), 13 to 15 mg/kg per day, is the standard therapy for PBC and should be offered to every patient. It has been shown to slow progression of the disease and prevent the need for liver transplantation, which is the last recourse for patients with end-stage disease. However, there is no effective therapy for PSC yet. Patients are managed symptomatically, with surgical or endoscopic interventions as needed in cases of significant biliary obstruction. Complications of chronic cholestasis are seen in both PBC and PSC, with pruritus and fatigue being the most common complaints. The first choice for the treatment of pruritus is still cholestyramine, starting at 4 g/d. The pathogenesis of fatigue is poorly understood in this population; unrecognized hypothyroidism should be excluded. The use of antidepressants is currently under evaluation, but there is no specific therapy for fatigue as of yet. For prevention of severe osteoporosis, we recommend supplementation with 800 IU vitamin D and 1500 mg calcium/d. In patients with PBC and established osteoporosis, the use of alendronate and vitamin K appears to cause an increase in bone mineral density. Further studies are necessary before either of these drugs is routinely recommended. Finally, fat-soluble vitamin deficiencies are noted with more advanced disease. We recommend that serum levels be checked in high-risk patients, and that vitamins are replaced as appropriate with water-soluble supplements. However, other causes of malabsorption must be ruled out, including pancreatic insufficiency and celiac sprue.     

The management of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a chronic cholestatic hepatobiliary disease that usually progresses to biliary cirrhosis and liver failure; it also predisposes to cholangiocarcinoma. The cause of PSC is unknown, although evidence suggests that the tissue damage is mediated by the immune system. There is an unexplained close association between PSC and inflammatory bowel disease, particularly in ulcerative colitis, which coexists in the majority of patients with PSC. No medical therapy has been proven to halt or reverse disease progression; however, recent preliminary evidence suggests that ursodeoxycholic acid (UDCA) in a high dose of 20 to 25 mg/kg may slow the disease process. Evidence from a pilot study suggests that the combination of UDCA and immunosuppressive therapy, such as prednisolone or azathioprine, may also increase efficacy. For patients with end-stage PSC, liver transplantation remains the only effective therapy, although there is clear evidence that PSC may recur in the liver allograft.     

High-dose ursodeoxycholic acid for the treatment of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a cholestatic liver disease that results in progressive fibrosis of intrahepatic and extrahepatic bile ducts. No effective therapy currently exists for this disease. Ursodeoxycholic acid (UDCA), a hydrophilic bile acid, is the most promising treatment option because of its benign side effect profile and documented benefit in the treatment of other cholestatic liver diseases, including primary biliary cirrhosis. Multiple studies using standard-dosage (8–15 mg/kg/d) and high-dosage (20–30 mg/kg/d) UDCA generally show improvement in liver chemistries in PSC patients, and several show improvement in liver histology. However, the majority of trials using UDCA in PSC are underpowered and fail to show improvements in clinically relevant endpoints, such as delayed progression to cirrhosis, portal hypertension, liver transplantation, development of cholangiocarcinoma, or death.     

The efficacy of ursodeoxycholic acid and bezafibrate combination therapy for primary biliary cirrhosis: A prospective, multicenter study.

Aim: Treatment with ursodeoxycholic acid (UDCA) improves the survival of stage I and II primary biliary cirrhosis (PBC) patients. However, new therapeutic options are needed for patients who are refractory to UDCA and for those whose disease is at an advanced stage. Bezafibrate could be useful in PBC treatment, since it increases phospholipid output into the bile and reduces the cytotoxicity of hydrophobic bile acids, which are increased with cholestasis. Methods: We conducted two prospective, multicenter randomized open studies in non-cirrhotic patients with PBC to evaluate the efficacy of bezafibrate. One study compared UDCA and bezafibrate monotherapy (study 1: 45 patients [37 females], mean age 55.9 years), and the other evaluated the addition of bezafibrate to patients who were refractory to UDCA (study 2: 21 patients [18 females], mean age 54.1 years). Results: Study 1 demonstrated that bezafibrate monotherapy was as effective as UDCA and study 2 revealed that bezafibrate combined with UDCA was effective in improving and maintaining biliary enzymes where the ineffectiveness of long-term treatment with UDCA was confirmed. Conclusion: This multicenter, randomized, open study revealed that combination therapy of bezafibrate and UDCA improved biliary enzymes in non-cirrhotic Japanese patients with PBC refractory to UDCA. Further studies are needed to evaluate whether combination therapy improves histological staging and prognosis.     

Adhesion molecule expression in primary sclerosing cholangitis and primary biliary cirrhosis.

There are conflicting reports regarding intercellular adhesion molecule-1 (ICAM-1) expression in primary sclerosing cholangitis (PSC) and primary biliary cirrhosis (PBC). Expression of adhesion molecules ICAM-1, lymphocyte adhesion molecule-1 (LFA-1), vascular cell adhesion molecule (VCAM), and E-selectin was examined together with HLA-DR in 16 liver biopsy specimens showing PSC and 12 specimens showing PBC. These were compared with biopsy specimens showing large duct obstruction (n = 7), chronic active hepatitis (n = 4), alcoholic liver disease (n = 4), and normal liver histological results (n = 5). ICAM-1 was detected on biliary epithelium in five of seven PSC specimens of histological stage 3 or 4, but not in nine early PSC specimens or in specimens from disease controls. In PBC, ICAM-1 was positive on three of 12 cases, two stage 2, and one stage 3. Nine of 16 PSC specimens (three of nine early, six of seven late disease) and six of 10 PBC specimens (three early, three late disease) were positive for HLA-DR. LFA-1 stained infiltrating inflammatory cells in PSC, PBC, and disease controls. In conclusion, ICAM-1 expression on biliary epithelium in PSC occurs mainly in late stage disease and therefore may be secondary to previous events inducing inflammation rather than of primary pathogenic importance. ICAM-1 expression in PBC is less common and not clearly associated with a particular disorder. Previous reports of ICAM-1 prevalence may have been biased towards end stage, pre-transplantation biopsy specimens.     

Formation of iso-ursodeoxycholic acid during administration of ursodeoxycholic acid in man

The appearance of iso-ursodeoxycholic acid (isoUDCA; 3 beta,7 beta-dihydroxy-5 beta-cholan-24-oic acid) in serum of patients with chronic cholestatic liver disease and of healthy subjects during administration of ursodeoxycholic acid (UDCA) is reported. Comparison of the mass spectrum of the newly appearing bile acid with that of authentic 3 beta,7 beta-dihydroxy-5 beta-cholan-24-oic acid revealed its identity as the 3 beta-epimer of UDCA. The appearance of 13C-isoUDCA in serum after ingestion of 13C-UDCA proved its product precursor relationship with UDCA. The putative intermediate in the epimerization of UDCA to isoUDCA, 3-oxo-7 beta-hydroxy-5 beta-cholan-24-oic acid, was identified in serum of patients with cholestatic liver disease during treatment with UDCA. Serum concentrations of isoUDCA after 4 weeks of UDCA treatment were 1.37 +/- 0.79 mumol/l (mean +/- S.D.) in eight patients with primary biliary cirrhosis (PBC), 1.25 +/- 0.91 mumol/l in six patients with primary sclerosing cholangitis (PSC) and 3.87 +/- 0.44 mumol/l in four healthy controls. The intestinal bacterial flora as well as microsomal enzymes of the liver may be involved in the epimerization of UDCA to isoUDCA as indicated by decreased serum levels of isoUDCA under antibiotic treatment with doxycycline (100 mg/day) in healthy subjects and a correlation (r = 0.873, p less than 0.001) between the hepatic microsomal function measured by the 14C-aminopyrine breath test and the fractional conversion of applied UDCA to isoUDCA (isoUDCA/UDCA + isoUDCA) in patients with PBC or PSC. Future studies of bile acid metabolism under UDCA treatment should include measurement of isoUDCA to further elucidate its biological role.     

Methotrexate improves biochemical tests in patients with primary biliary cirrhosis who respond incompletely to ursodiol.

BACKGROUND & AIMS: Primary biliary cirrhosis (PBC) is a chronic cholestatic liver disease of presumed autoimmune etiology. Ursodeoxycholic acid (UDCA), methotrexate, and colchicine each have shown promise in its treatment. The value of combining 2 or 3 of these drugs is uncertain. The aim of this study was to determine whether addition of methotrexate to the treatment regimen improves results of liver biochemical tests in patients with antimitochondrial antibody-positive PBC who responded incompletely to treatment with UDCA and colchicine. METHODS: Methotrexate was added to the treatment regimen of 10 consecutive patients with antimitochondrial antibody-positive PBC who had an incomplete response to therapy with UDCA alone or in combination with colchicine. The primary end point was biochemical response. Symptoms and histological changes were also recorded. RESULTS: Addition of methotrexate to the UDCA plus colchicine regimen was associated with a significant reduction in serum alkaline phosphatase (ALP) levels beyond those found with UDCA and colchicine alone or in combination. Median ALP concentration was 389 IU (range, 247-1013 IU) at baseline, 300 IU (range, 155-467 IU) after treatment with UDCA plus colchicine, and 120 IU (range, 66-351 IU) after treatment with methotrexate. CONCLUSIONS: Addition of methotrexate to a regimen of UDCA and colchicine may be beneficial for patients with PBC who respond incompletely to treatment with UDCA and colchicine.     

Metronidazole and ursodeoxycholic acid for primary sclerosing cholangitis: a randomized placebo-controlled trial

No effective medical therapy is currently available for primary sclerosing cholangitis (PSC). Ursodeoxycholic acid (UDCA) improves liver enzymes, but its effect on liver histology is controversial. Metronidazole (MTZ) prevents PSC-like liver damage in animal models and reduces intestinal permeability. We recruited 80 patients with PSC into a randomized placebo-controlled study to evaluate the effect of UDCA and MTZ (UDCA/MTZ) compared with UDCA/placebo on the progression of PSC. Patients (41 UDCA/placebo and 39 UDCA/MTZ) were followed every third month. Assessment of liver function test, histological stage and grade, and cholangiography (via ERCP) at baseline showed no differences between the groups. After 36 months, serum aminotransferases gamma-glutamyltransferase, and alkaline phosphatase (ALP) decreased markedly in both groups, serum ALP more significantly in the UDCA/MTZ group (-337 +/- 54 U/L, P < .05) compared with the UDCA/placebo group. The New Mayo Risk Score decreased markedly only in the UDCA/MTZ group (-0.50 +/- 0.13, P < .01). The number of patients with improvement of stage (P < .05) and grade (P < .05) was higher in the combination group. ERCP findings showed no progression or improvement in 77% and 68% of patients on UDCA/MTZ and UDCA/placebo, respectively. In conclusion, combining MTZ with UDCA in PSC improved serum ALP levels and New Mayo Risk Score, but no statistically significant effect on disease progression as assessed via liver histology or ERCP was seen. Long-term studies using a higher dose of UDCA combined with MTZ in larger patient populations are indicated.     

Intrahepatic cholestasis: clinical and nosological classification. Critical survey of personal experience

We reviewed 20 patients (16 females and 4 males) with intrahepatic cholestasis and recognised the following miscellaneous disorders: 12 primary biliary cirrhosis (PBC), 3 primary sclerosing cholangitis (PSC), 1 immune cholangiopathy (IC), 3 liver sarcoidosis and 1 cholestasis with Horton's arteritis. The aim of the study was to identify potentially differetiating clinical and biochemical findings in intrahepatic cholestasis. Sixty females were affected with changes reflecting a cholestatic pattern including an elevated alkaline phosphatasis and gammaglutamyltransferase level. Pruritus was found in 50 percent of PBC patients; fever addressed often, in liver sarcoidosis and Horton's arteritis. A striking increase of unesterified cholesterol was a common feature of PBC. An elevated polyclonal serum IgM in PBC such as in PSC. A circulating IgM antimitochondrial antibody and antinuclear antibodies were found in 90 percent of PBC patients; isolated antinuclear antibodies were detected in immune colangiopathy patients (IC). Liver biopsy was necessary to establish the diagnosis of intrahepatic cholestasis. Overlapping histopathologic features made diagnosis hard in cholestatic disorders, all but in liver sarcoidosis. Treatment with UDCA or TUDCA+/-colchicin, reduced cholestatic enzymes in 85 percent of PBC cohort, while it was unsuccessful in PSC-group. Steroid treatment was successful in sarcoidosis, Horton's arteritis and immune colangiopathy. Cy A did not improve clinical and biochemical features in PBC.     

Ursodeoxycholic acid for patients with primary biliary cirrhosis: an updated systematic review and meta-analysis of randomized clinical trials using Bayesian approach as sensitivity analyses

OBJECTIVES: Ursodeoxycholic acid (UDCA) is used for primary biliary cirrhosis (PBC), but the beneficial effects remain controversial. METHODS: We performed an updated systematic review to evaluate the benefits and harms of UDCA in patients with PBC. We included randomized clinical trials evaluating UDCA versus placebo or no intervention in patients with PBC. The primary outcomes, mortality and mortality or liver transplantation, were reported as relative risk (RR) with 95% confidence interval (CI). Meta-regression was used to investigate the associations between UDCA effects and the trial's risk of bias, UDCA dose, duration, and PBC severity at trial entry. We used Bayesian meta-analytic approaches as sensitivity analyses. RESULTS: Sixteen randomized clinical trials (1,447 patients) evaluating UDCA versus placebo or no intervention were identified. Over half of the trials had high risk of bias. Comparing with placebo or no intervention, UDCA did not significantly affect mortality (RR 0.97, 95% CI 0.67-1.42) and mortality or liver transplantation (RR 0.92, 95% CI 0.71-1.21). The findings were supported by the Bayesian meta-analyses. Meta-regression analyses suggested that UDCA effects seem to be associated with patient's disease severity and trial duration. UDCA did not improve pruritus, fatigue, autoimmune conditions, liver histology, or portal pressure. UDCA seemed to improve biochemical variables, such as serum bilirubin, and ascites and jaundice, but the findings were based on few trials with sparse data. The use of UDCA was significantly associated with adverse events, mainly weight gain. CONCLUSIONS: This updated systematic review did not demonstrate any benefit of UDCA on mortality and mortality or liver transplantation in patients with PBC.     

Autoimmune liver disease: diagnosis and therapy

Autoimmune Hepatitis (AIH), primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and overlap syndromes of these three disease entities are regarded as autoimmune liver diseases. These conditions are important differential diagnoses of elevated liver function tests as about 10 % of liver transplantations in Europe and North America are for these indications. The diagnosis is often difficult but can be facilitated by sequential measurement of relevant autoantibodies, exclusion of other liver disease, ultrasound, ERCP and liver histology. In AIH immunosuppressive therapy has been shown to prevent or stop the development of cirrhosis and improve the prognosis of the patients decisively. In other autoimmune liver diseases this evidence is missing making individual therapeutic decisions necessary. Ursodesoxycholic acid (UDCA) seems to slow disease progression in particular in early stages of PBC.     

Treatment of primary biliary cirrhosis with ursodeoxycholic acid

This study was undertaken to evaluate the efficacy of ursodeoxycholic acid (UDCA) in the treatment of primary biliary cirrhosis (PBC). Three patients with PBC (stage II) have been treated with UDCA (Ursofalk and Falk Pharma, Freiburg, Germany)--of 10 mg/kg daily dosage in the course of three years. Patients with well-defined PBC underwent complete history, physical examination, liver chemistries, ultrasonography and liver biopsy. Liver chemistries were determined every three months. A control liver biopsy was performed to one of the patient, an year after the beginning of the treatment. UDCA was well tolerated and showed no side effects. The most obvious benefit of UDCA was its favourable effect on serum biochemistries. Its use was associated with the delayed progression of the disease.     

Cytoprotection with ursodeoxycholic acid: effect in chronic non-cholestatic and chronic cholestatic liver disease.

Studies in vitro and in vivo show that hydrophobic bile acids tend to accumulate in the liver tissue in chronic liver disease, thus damaging hepatocyte membranes. Ursodeoxycholic acid (UDCA) is a hydrophilic bile acid which counteracts hepatotoxicity of more hydrophobic bile acids by partially replacing the pool of bile acids in the liver and/or by inhibiting the intestinal absorption of toxic bile acids. UDCA seems safe and effective in the early stages of primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and possibly in other severe cholestatic syndromes of infancy. Moreover, there is increasing evidence that UDCA improves the common indices of liver function in chronic non-cholestatic hepatic disorders including active cirrhosis, though maintaining the residual functional liver mass. This article reviews the cytoprotective effect of UDCA in chronic cholestatic and non-cholestatic liver disease based on the results of major clinical trials on this topic.     

The association of histological progression with biochemical response to ursodeoxycholic acid in primary biliary cholangitis

Primary biliary cholangitis (PBC) is currently diagnosed at an early stage; therefore, the number of patients with PBC without symptoms at the time of diagnosis is increasing. However, up to 30% of patients with PBC exhibit the suboptimal response to ursodeoxycholic acid (UDCA) and are at high risk of end-stage liver disease. Obeticholic acid is an approved second-line therapy for patients with PBC that are refractory to UDCA. Novel surrogate endpoints are required to identify individuals eligible for second-line therapies. An inadequate biochemical response to UDCA is a useful predictor of poor outcomes in patients with PBC. In addition to UDCA effects on biochemical parameters, histological outcomes could be considered as candidate surrogate endpoints. Alterations in liver histology are used as surrogate endpoints in clinical studies. However, current staging systems are insufficient to determine PBC disease severity and progression because of the pathological heterogeneity of the disease. Histological features at baseline and biochemical response to UDCA treatment can affect the disease course of PBC. Therefore, novel surrogate endpoints must be represented by parameters characterized by histological outcomes and treatment responses in PBC. In this review, we discuss the existing histological parameters and newly created factors to identify patients with PBC who are at a high risk of developing end-stage liver disease and, consequently, the potential need for additional treatments.     

Ursodeoxycholic acid 'mechanisms of action and clinical use in hepatobiliary disorders'

UDCA exerts its beneficial effect in liver diseases through a diverse, probably, complementary array of mechanisms. The clinical use and efficacy of UDCA in PBC have been evident. UDCA may also have a place in the management of PSC, ICP, cystic fibrosis, PFIC and GVHD involving the liver, although, more studies are needed to further determine its therapeutic potential in these diseases and in other hepatobiliary disorders such as liver allograft rejection, drug and TPN-induced cholestasis, NASH, and alcoholic liver disease.