Update on primary sclerosing cholangitis

CD4+ T cells from patients with primary sclerosing cholangitis exhibit reduced apoptosis and down-regulation of proapoptotic Bim in peripheral blood

The pathogenesis of the progressive liver disease, primary sclerosing cholangitis (PSC), remains largely elusive. The strong genetic association with HLA loci suggests that T cell–dependent, adaptive immune reactions could contribute to disease pathogenesis. Recent studies have indicated that PSC is also associated with polymorphisms in the locus encoding for proapoptotic Bim (BCL2L11). Bim is crucial for the maintenance of immunologic tolerance through induction of apoptosis in activated T cells. Of interest with regard to PSC is the finding that BCL2L11-deficient mice develop periductular infiltrates. We, therefore, investigated, whether defective apoptosis of T cells might contribute to the phenotype of PSC. Thus, we induced apoptosis of T cells from patients with PSC and controls by repeated T cell receptor (TCR) stimulation or cytokine withdrawal. We found that CD4+ T cells, but not CD8+ T cells, from patients with PSC exhibited significantly reduced apoptosis in response to both, TCR restimulation or cytokine withdrawal. This increased apoptosis resistance was associated with significantly reduced up-regulation of proapoptotic Bim in T cells from patients with PSC. However, T cell apoptosis did not seem to be influenced by the previously described BCL2L11 polymorphisms. Reduced CD4+ T cell apoptosis in patients with PSC was not due to reduced cell activation, as indicated by a similar surface expression of the activation markers CD69, CD25, and CD28 in T cells from patients and controls. Thus, decreased apoptosis of activated CD4+ T cells may be part of the immune dysregulation observed in patients with PSC.

Systematic review: recurrent autoimmune liver diseases after liver transplantation

BACKGROUND

Autoimmune liver diseases (AILD) constitute the third most common indication for liver transplantation (LT) worldwide. Outcomes post LT are generally good but recurrent disease is frequently observed.

AIMS

To describe the frequency and risk factors associated with recurrent AILD post-LT and provide recommendations to reduce the incidence of recurrence based on levels of evidence.

METHODS

A systematic review was performed for full-text papers published in English-language journals, using the keywords 'autoimmune hepatitis (AIH)', 'primary biliary cholangitis and/or cirrhosis (PBC)', 'primary sclerosing cholangitis (PSC)', 'liver transplantation' and 'recurrent disease'. Management strategies to reduce recurrence after LT were classified according to grade and level of evidence.

RESULTS

Survival rates post-LT are approximately 90% and 70% at 1 and 5 years and recurrent disease occurs in a range of 10-50% of patients with AILD. Recurrent AIH is associated with elevated liver enzymes and IgG before LT, lymphoplasmacytic infiltrates in the explants and lack of steroids after LT (Grade B). Tacrolimus use is associated with increased risk; use of ciclosporin and preventive ursodeoxycholic acid with reduced risk of PBC recurrence (all Grade B). Intact colon, active ulcerative colitis and early cholestasis are associated with recurrent PSC (Grade B).

CONCLUSIONS

Recommendations based on grade A level of evidence are lacking. The need for further study and management includes active immunosuppression before liver transplantation and steroid use after liver transplantation in autoimmune hepatitis; selective immunosuppression with ciclosporin and preventive ursodeoxycholic acid treatment for primary biliary cholangitis; and improved control of inflammatory bowel disease or even colectomy in primary sclerosing cholangitis.

Diagnostic value of microRNAs as biomarkers for cholangiocarcinoma

BACKGROUND

It has been reported that microRNAs might serve as biomarkers for cholangiocarcinoma (CCA) detection, but their diagnostic accuracy are unclear and controversial.

AIM

To evaluate the diagnostic accuracy of microRNAs for CCA.

MATERIALS AND METHODS

PubMed, Embase, Web of Science and Cochrane Library were systematically searched to identify relevant articles by using the key words "cholangiocarcinoma" and "microRNA". The methodological quality of each study was assessed by QUADAS-2. According to the inclusive and exclusive criteria, 11 articles were identified and analyzed by Meta-disc software v.1.4 and STATA 12.0 software package.

RESULTS

11 articles with 430 CCA patients and 406 controls were identified. The results showed that the pooled sensitivity was 0.756 (95% CI: 0.693-0.810), specificity was 0.914 (95% CI: 0.861-0.947), positive likelihood ratio was 8.747 (95% CI: 5.320-14.381), negative likelihood ratio was 0.267 (95% CI: 0.208-0.341) and diagnostic odds ratio was 32.791 (95% CI: 17.327, 62.060). In addition, the area under the summary ROC cure (AUC) was 0.90 (95% CI: 0.87-0.93).

CONCLUSION

MicroRNAs have great potential as biomarkers for the diagnosis of CCA patients. However, the clinical application of microRNA assays for CCA diagnosis still needs further validation by more prospective studies.

Differentiation of benign and malignant hilar bile duct stenosis

BACKGROUND

Failure to differentiate benign and malignant hilar bile duct stenosis may lead to inappropriate treatment. We retrospectively analyzed the methods for differentiation.

MATERIALS AND METHODS

A total of 53 patients with hilar bile duct stenosis were included, comprising 41 malignant cases (hilar cholangiocarcinoma) and 12 benign cases (six primary sclerosing cholangitis and six IgG4-associated sclerosing cholangitis). Data of clinical histories, laboratory tests, imaging studies, and liver pathologies were collected, and comparison was made between benign and malignant groups.

RESULTS

Compared with malignant group, patients in the benign group were more likely to have multiorgan involvement of clinical histories (P < 0.001). There was no difference on bilirubin, liver enzyme, and serum tumor marker between the two groups, whereas serum IgG4 levels were higher in the benign group (P = 0.003). Patients in the benign group were more likely to have pancreatic changes (P < 0.001) and multiple-segmental bile duct stenosis (P < 0.001) on imaging. Compared with the malignant group, patients in the benign group were more likely to show severe periportal inflammation in noninvolved liver (P < 0.001), fibrosis around intrahepatic bile duct (P < 0.001), and more IgG4-positive plasma cells (P < 0.001) on liver pathology.

CONCLUSIONS

Benign lesion should be considered for patients with history of multiorgan involvement, pancreas changes, or multiple-segmental bile duct stenosis on imaging. Liver biopsy could be helpful for differential diagnosis before surgery.

Severe hypercholesterolemia and liver disease in a 3-year old

Lipoprotein-X, which is composed of phospholipids and non-esterified cholesterol, is an abnormal lipoprotein with a density range similar to LDL-C. The two most common ways which lipoprotein-X accumulates is from reflux of bile salts into plasma or deficiency in lecithin cholesterol acyltransferase. This is a case of severe hypercholesterolemia and liver disease in a 3- year old male that presented with pruritus, pale stool, scleral ictus, and abdominal distention. He was diagnosed with primary sclerosing cholangitis which was confirmed by liver biopsy. Our patient was treated with steroids and immunomodulator therapy which was associated with significant reduction in cholestasis and LDL-C levels. Lipoprotein-X has several properties that make it anti-atherogenic, which raises the question if treatment for hypercholesterolemia should be initiated.

Ulcerative Colitis with and without Primary Sclerosing Cholangitis: Two Different Diseases?

Background

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown origin and an important hepatobiliary complication of inflammatory bowel diseases (IBD), especially ulcerative colitis (UC). When further differentiated, about 3-8% of UC patients suffer from PSC, whereas among Crohn's disease patients the reported prevalence of PSC is probably between 1 and 3.5%. Although it was reported from Japan that the frequency of PSC in UC was only 34%, the same registry data indicated that the prevalence was up to 57% among young patients with PSC even in Japan, which is comparable to the 60-80% in Europe and the US. Additionally, the clinical features of UC in patients with PSC are different from those in patients without PSC, for instance, rectal sparing and right-sided dominance.

Summary

The strong link between atypical IBD and PSC suggests that the pathogenesis of PSC involves pathology of the gut, including abnormal gut microbiota and aberrant activation of mucosal lymphocytes. These seem to be different in UC PSC as compared to the pathology of typical UC.

Key Messages

The key to solving the question 'Is there a difference between East and West?' are genetic studies, genome-wide association studies of PSC in particular, which have already been performed in the West and are strongly warranted in the East.

Analysis of five chronic inflammatory diseases identifies 27 new associations and highlights disease-specific patterns at shared loci

We simultaneously investigated the genetic landscape of ankylosing spondylitis, Crohn's disease, psoriasis, primary sclerosing cholangitis and ulcerative colitis to investigate pleiotropy and the relationship between these clinically related diseases. Using high-density genotype data from more than 86,000 individuals of European ancestry, we identified 244 independent multidisease signals, including 27 new genome-wide significant susceptibility loci and 3 unreported shared risk loci. Complex pleiotropy was supported when contrasting multidisease signals with expression data sets from human, rat and mouse together with epigenetic and expressed enhancer profiles. The comorbidities among the five immune diseases were best explained by biological pleiotropy rather than heterogeneity (a subgroup of cases genetically identical to those with another disease, possibly owing to diagnostic misclassification, molecular subtypes or excessive comorbidity). In particular, the strong comorbidity between primary sclerosing cholangitis and inflammatory bowel disease is likely the result of a unique disease, which is genetically distinct from classical inflammatory bowel disease phenotypes.

Genetics in PSC: what do the "risk genes" teach us?

A role of genetics in primary sclerosing cholangitis (PSC) development is now firmly established. A total of 16 risk genes have been reported at highly robust ("genome-wide") significance levels, and ongoing efforts suggest that the list will ultimately be considerably longer. Importantly, this genetic risk pool so far accounts for less than 10 % of an estimated overall PSC susceptibility. The relative importance of genetic versus environmental factors (including gene-gene and gene-environment interactions) in remaining aspects of PSC pathogenesis is unknown, and other study designs than genome-wide association studies are needed to explore these aspects. For some of the loci, e.g. HLA and FUT2, distinct interacting environmental factors may exist, and working from the genetic associations may prove one valid path for determining the specific nature of environmental triggers. So far the biological implications for PSC risk genes are typically merely hypothesized based on previously published literature, and there is therefore a strong need for dedicated translational studies to determine their roles within the specific disease context of PSC. Apparently, most risk loci seem to involve in a subset of biological pathways for which genetic associations exist in a multitude of immune-mediated diseases, accounting for both inflammatory bowel disease as well as prototypical autoimmunity. In the present article, we will survey the current knowledge on PSC genetics with a particular emphasis on the pathophysiological insight potentially gained from genetic risk loci involving in this profound immunogenetic pleiotropy.

TGR5: pathogenetic role and/or therapeutic target in fibrosing cholangitis?

Primary sclerosing cholangitis (PSC) is a chronic inflammatory disease affecting the intrahepatic and extrahepatic biliary tree leading to bile duct strictures, progressive cholestasis, and development of liver fibrosis and cirrhosis. The pathogenesis of PSC is still elusive; however, both an immune-mediated injury of the bile ducts as well as increased recruitment of intestinal-primed T lymphocytes to the biliary tracts seem to contribute to disease development and progression. TGR5 (Gpbar-1) is a G-protein-coupled receptor responsive to bile acids, which is expressed in cholangiocytes, intestinal epithelial cells, and macrophages of the liver and intestine as well as in CD14-positive monocytes of the peripheral blood. Activation of TGR5 in biliary epithelial cells promotes chloride and bicarbonate secretion, triggers cell proliferation, and prevents apoptotic cell death. In immune cells, stimulation of TGR5 inhibits cytokine expression and secretion, thus reducing systemic as well as hepatic and intestinal inflammation. The expression pattern of TGR5 in the liver and intestine as well as the potential protective functions of TGR5 suggest a role for this receptor in the pathogenesis of PSC. While mutations in the coding region of the TGR5 gene are too rare to contribute to overall disease susceptibility, the expression and localization of the receptor have not been studied in PSC livers. Pharmacological activation of TGR5 in mice promotes protective mechanisms in biliary epithelial cells and reduces hepatic and systemic inflammation; however, it also provokes pruritus. Further studies are needed to predict the potential benefits as well as side effects of TGR5 agonist treatment in PSC patients.

Brazilian society of hepatology recommendations for the diagnosis and management of autoimmune diseases of the liver

ABSTRACT In order to draw evidence-based recommendations concerning the management of autoimmune diseases of the liver, the Brazilian Society of Hepatology has sponsored a single-topic meeting in October 18th, 2014 at São Paulo. An organizing committee comprised of seven investigators was previously elected by the Governing Board to organize the scientific agenda as well as to select twenty panelists to make a systematic review of the literature and to present topics related to the diagnosis and treatment of autoimmune hepatitis, primary sclerosing cholangitis, primary biliary cirrhosis and their overlap syndromes. After the meeting, all panelists gathered together for the discussion of the topics and the elaboration of those recommendations. The text was subsequently submitted for suggestions and approval of all members of the Brazilian Society of Hepatology through its homepage. The present paper is the final version of the reviewed manuscript organized in topics, followed by the recommendations of the Brazilian Society of Hepatology.

Is gallstone disease associated with inflammatory bowel diseases? A meta-analysis

OBJECTIVE

To investigate the association between inflammatory bowel disease (IBD) and gallstone disease (GD) by performing a meta-analysis.

METHODS

PubMed, Medline, Embase, Web of Science and the Cochrane Library were searched for relevant articles published between January 1980 and February 2015. All statistical analyses were performed using STATA 12.0. A fixed-effects model was adopted; heterogeneity was evaluated by χ(2) test and I(2) statistic; publication bias was assessed by Begg's and Egger's tests.

RESULTS

Five studies qualified for inclusion in the meta-analysis. Patients with IBD had a significantly higher prevalence of GD than those in the control group [odds ratio (OR) 1.72, 95% confidence interval (CI) 1.40-2.12, P < 0.0001]. Subgroup analyses showed a significantly higher prevalence of GD in patients with Crohn's disease (CD) (OR 2.05, 95% CI 1.61-2.63, P < 0.0001). However, no significant difference in the prevalence of GD was observed between patients with ulcerative colitis (UC) and controls (OR 1.12, 95% CI 0.75-1.68, P = 0.585). Studies from Italy, Sweden and the UK revealed a higher prevalence of GD in patients with IBD. No heterogeneity (I(2) = 25.2%, P = 0.228) or publication bias was observed in our meta-analysis (Begg's test, P = 0.711; Egger's test, P = 0.805).

CONCLUSIONS

Our meta-analysis suggests there is a trend towards higher prevalence of GD in IBD patients, and especially in patients with CD. More rigorous, large-scale multi-center studies are required to investigate the association between GD and IBD.

Activation of biliary tree stem cells within peribiliary glands in primary sclerosing cholangitis

BACKGROUND & AIMS

Primary sclerosing cholangitis (PSC) is characterised by fibro-stenosing strictures involving extrahepatic and/or large intrahepatic bile ducts. Mechanisms leading to bile duct injury are poorly understood. We aimed to study the biliary tree stem cell compartment located in peribiliary glands of extrahepatic and large intrahepatic bile ducts and its role in the pathogenesis of biliary fibrosis in PSC.

METHODS

Specimens containing extrahepatic or large intrahepatic bile ducts were obtained from normal liver (n=6), liver explants from patients with PSC (n=11), and primary biliary cirrhosis (n=6). Specimens were processed for histology, immunohistochemistry and immunofluorescence.

RESULTS

In PSC samples, progressive hyperplasia and mucinous metaplasia of peribiliary glands were observed in large ducts with fibrosis, but not in inflamed ducts without fibrosis. Peribiliary gland hyperplasia was associated with progressive biliary fibrosis and the occurrence of dysplastic lesions. Hyperplasia of peribiliary glands was determined by the expansion of biliary tree stem cells, which sprouted towards the surface epithelium. In PSC, peribiliary glands and myofibroblasts displayed enhanced expression of Hedgehog pathway components. Peribiliary glands in ducts with onion skin-like fibrosis expressed epithelial-to-mesenchymal transition traits associated with components of Hedgehog pathway, markers of senescence and autophagy.

CONCLUSIONS

The biliary tree stem cell compartment is activated in PSC, its activation contributes to biliary fibrosis, and is sustained by the Hedgehog pathway. Our findings suggest a key role for peribiliary glands in the progression of bile duct lesions in PSC and could explain the associated high risk of cholangiocarcinoma.

Indications and Outcomes in Liver Transplantation in Patients With Primary Sclerosing Cholangitis in Norway

Supplemental digital content is available in the text.

Background

Primary sclerosing cholangitis (PSC) is 1 of the leading causes of liver transplantation (LTX) in Scandinavia, and an increasing number of PSC patients have been transplanted in Norway during the last 2 decades. This trend is partly attributable to the recently established practice in Norway of offering LTX to PSC patients with cholangiocellular dysplasia. Based on the controversy associated with this practice, we herein aimed to report the main features and outcomes of our LTX program in PSC.

Methods

The primary indication for LTX (quality of life/end-stage liver disease or suspected neoplasia) was retrospectively determined for 222 patients undergoing LTX for PSC or other autoimmune liver diseases (primary biliary cirrhosis/autoimmune hepatitis) with at least 5 years of follow-up.

Results

In PSC patients impaired quality of life (43.5%) and end-stage liver disease (38.4%) were the most frequent indications for LTX, whereas suspected neoplasia accounted for 18.1%. The proportion of PSC patients with manifest encephalopathy, variceal bleeding, or ascites declined over time. In patients with suspected neoplasia as the primary indication for LTX (n = 25), neoplasia was confirmed in the explanted liver in 20 patients (80%). Five-year survival rates for PSC patients transplanted between 2001 and 2009 were 91.9% for patients receiving LTX due to impaired quality of life or end-stage liver disease and 83.3% for suspected neoplasia.

Conclusions

The PSC patients are increasingly listed for LTX at an earlier stage of their liver disease. In patients with suspected neoplasia before LTX, 5-year survival was acceptable, despite confirmation of neoplasia in 80% of the liver explants.

MicroRNAs in Serum and Bile of Patients with Primary Sclerosing Cholangitis and/or Cholangiocarcinoma

BACKGROUND AND AIM

Patients with primary sclerosing cholangitis (PSC) are at high risk for the development of cholangiocarcinoma (CC). Analysis of micro ribonucleic acid (MiRNA) patterns is an evolving research field in biliary pathophysiology with potential value in diagnosis and therapy. Our aim was to evaluate miRNA patterns in serum and bile of patients with PSC and/or CC.

METHODS

Serum and bile from consecutive patients with PSC (n = 40 (serum), n = 52 (bile)), CC (n = 31 (serum), n = 19 (bile)) and patients with CC complicating PSC (PSC/CC) (n = 12 (bile)) were analyzed in a cross-sectional study between 2009 and 2012. As additional control serum samples from healthy individuals were analyzed (n = 12). The miRNA levels in serum and bile were determined with global miRNA profiling and subsequent miRNA-specific polymerase chain reaction-mediated validation.

RESULTS

Serum analysis revealed significant differences for miR-1281 (p = 0.001), miR-126 (p = 0.001), miR-26a (p = 0.001), miR-30b (p = 0.001) and miR-122 (p = 0.034) between patients with PSC and patients with CC. All validated miRNAs were significantly lower in healthy individuals. MiR-412 (p = 0.001), miR-640 (p = 0.001), miR-1537 (p = 0.003) and miR-3189 (p = 0.001) were significantly different between patients with PSC and PSC/CC in bile.

CONCLUSIONS

Patients with PSC and/or CC have distinct miRNA profiles in serum and bile. Furthermore, miRNA concentrations are different in bile of patients with CC on top of PSC indicating the potential diagnostic value of these miRNAs.

The biliary epithelium presents antigens to and activates natural killer T cells

Cholangiocytes express antigen-presenting molecules, but it has been unclear whether they can present antigens. Natural killer T (NKT) cells respond to lipid antigens presented by the major histocompatibility complex class I-like molecule CD1d and are abundant in the liver. We investigated whether cholangiocytes express CD1d and present lipid antigens to NKT cells and how CD1d expression varies in healthy and diseased bile ducts. Murine and human cholangiocyte cell lines as well as human primary cholangiocytes expressed CD1d as determined by flow cytometry and western blotting. Murine cholangiocyte cell lines were able to present both exogenous and endogenous lipid antigens to invariant and noninvariant NKT cell hybridomas and primary NKT cells in a CD1d-dependent manner. A human cholangiocyte cell line, cholangiocarcinoma cell lines, and human primary cholangiocytes also presented exogenous CD1d-restricted antigens to invariant NKT cell clones. CD1d expression was down-regulated in the biliary epithelium of patients with late primary sclerosing cholangitis, primary biliary cirrhosis, and alcoholic cirrhosis compared to healthy controls.

CONCLUSIONS

Cholangiocytes express CD1d and present antigens to NKT cells and CD1d expression is down-regulated in diseased biliary epithelium, findings which show that the biliary epithelium can activate an important lymphocyte subset of the liver. This is a potentially important immune pathway in the biliary system, which may be capable of regulating inflammation in the context of biliary disease.

Primary sclerosing cholangitis: a clinical update

INTRODUCTION

Primary sclerosing cholangitis (PSC) is a progressive cholestatic disorder that ultimately can lead to cirrhosis, liver failure, malignancy and death. It is strongly associated with inflammatory bowel disease (IBD), and though a rare disease, its incidence is increasing. There are no proven medical therapies for PSC.

SOURCES OF DATA

Ovid Medline was utilised to search for articles with keywords 'sclerosing cholangitis' and 'cholangiocarcinoma' and containing titles 'primary sclerosing cholangitis', and references of these papers were cross-referenced for further relevant manuscripts.

AREAS OF AGREEMENT

PSC is a rare disease, and there is a strong association with risk loci within the major histocompatibility complex and other genes common to other autoimmune diseases. PSC is a premalignant condition, associated with higher rates of hepatobiliary and colorectal cancer in patients with ulcerative colitis (UC).

AREAS OF CONTROVERSY

The pathogenesis is unclear, and competing theories exist surrounding toxic bile acids, enhanced homing of particular T cells from the gut to the liver and increased passage of toxins to the liver through a permeable bowel wall. It is unclear whether the higher rate of colonic cancer in PSC/UC occurs in PSC/Crohn's disease. Ursodeoxycholic acid therapy reduces liver enzymes but has not been shown to improve survival. It may reduce the prevalence of bowel cancer.

GROWING POINTS

Recent genetic studies have revealed new risk loci, pointing to the importance of the immune system and its interaction with the biome.

AREAS TIMELY FOR DEVELOPING RESEARCH

On the basis of the genetic studies discussed earlier, novel agents are being developed and trialled in the treatment of PSC.

Primary sclerosing cholangitis - the Norwegian experience

Research related to primary sclerosing cholangitis (PSC) has since 1980 been a major activity at the Oslo University Hospital Rikshospitalet. The purpose of this publication is to describe the development of this research, the impact of this research on the clinical handling of the patients, and finally to describe what we believe are the most urgent, remaining problems to be solved. During the early years, our research dealt primarily with clinical aspects of the disease. The concomitant inflammatory bowel disease (IBD) seen in most patients with PSC was a major interest and we also started looking into genetic associations of PSC. Prognosis, malignancy development and treatment with special emphasis on transplantation have later been dealt with. These activities has had impact on several aspects of PSC management; when and how to diagnose PSC and variant forms of PSC, how to handle IBD in PSC and how to deal with the increased rate of malignancy? The problems remaining to be solved are many. What is the role of the gut and the gut microbiota in the development of PSC? Do the PSC patients have an underlying disturbance in the bile homeostasis? And how does the characteristic type of fibrosis in PSC develop? The genetic studies have supported a role for the adaptive immune system in the disease development, but how should this be dealt with? Importantly, the development of malignancy in PSC is still not understood, and we lack appropriate medical treatment for our patients.

Outcomes of liver transplantation for end-stage biliary disease: A comparative study with end-stage liver disease

AIM: To evaluate the outcomes of patients with end-stage biliary disease (ESBD) who underwent liver transplantation, to define the concept of ESBD, the criteria for patient selection and the optimal operation for decision-making.

METHODS: Between June 2002 and June 2014, 43 patients with ESBD from two Chinese organ transplantation centres were evaluated for liver transplantation. The causes of liver disease were primary biliary cirrhosis (n = 8), cholelithiasis (n = 8), congenital biliary atresia (n = 2), graft-related cholangiopathy (n = 18), Caroli’s disease (n = 2), iatrogenic bile duct injury (n = 2), primary sclerosing cholangitis (n = 1), intrahepatic bile duct paucity (n = 1) and Alagille’s syndrome (n = 1). The patients with ESBD were compared with an end-stage liver disease (ESLD) case control group during the same period, and the potential prognostic values of multiple demographic and clinical variables were assessed. The examined variables included recipient age, sex, pre-transplant clinical status, pre-transplant laboratory values, operation condition and postoperative complications, as well as patient and allograft survival rates. Survival analysis was performed using Kaplan-Meier curves, and the rates were compared using log-rank tests. All variables identified by univariate analysis with P values < 0.100 were subjected to multivariate analysis. A Cox proportional hazard regression model was used to determine the effect of the study variables on outcomes in the study group.

RESULTS: Patients in the ESBD group had lower model for end-stage liver disease (MELD)/paediatric end-stage liver disease (PELD) scores and a higher frequency of previous abdominal surgery compared to patients in the ESLD group (19.2 ± 6.6 vs 22.0 ± 6.5, P = 0.023 and 1.8 ± 1.3 vs 0.1 ± 0.2, P = 0.000). Moreover, the operation time and the time spent in intensive care were significantly higher in the ESBD group than in the ESLD group (527.4 ± 98.8 vs 443.0 ± 101.0, P = 0.000, and 12.74 ± 6.6 vs 10.0 ± 7.5, P = 0.000). The patient survival rate in the ESBD group was not significantly different from that of the ESBD group at 1, 3 and 5 years (ESBD: 90.7%, 88.4%, 79.4% vs ESLD: 84.9%, 80.92%, 79.0%, χ² = 0.194, P = 0.660). The graft-survival rates were also similar between the two groups at 1, 3 and 5 years (ESBD: 90.7%, 85.2%, 72.7% vs ESLD: 84.9%, 81.0%, 77.5%, χ² = 0.003, P = 0.958). Univariate analysis identified MELD/PELD score (HR = 1.213, 95%CI: 1.081-1.362, P = 0.001) and bleeding volume (HR = 0.103, 95%CI: 0.020-0.538, P = 0.007) as significant factors affecting the outcomes of patients in the ESBD group. However, multivariate analysis revealed that MELD/PELD score (HR = 1.132, 95%CI: 1.005-1.275, P = 0.041) was the only negative factor that was associated with short survival time.

CONCLUSION: MELD/PELD criteria do not adequately measure the clinical characteristics and staging of ESBD. The allocation system based on MELD/PELD criteria should be re-evaluated for patients with ESBD.

Knockdown of ezrin causes intrahepatic cholestasis by the dysregulation of bile fluidity in the bile duct epithelium in mice

Cholangiopathies share common features, including bile duct proliferation, periportal fibrosis, and intrahepatic cholestasis. Damage of biliary epithelium by autoimunne disorder, virus infection, toxic compounds, and developmental abnormalities causes severe progressive hepatic disorders responsible for high mortality. However, the etiologies of these cholestatic diseases remain unclear because useful models to study the pathogenic mechanisms are not available. In the present study, we have found that ezrin knockdown (Vil2(kd/kd) ) mice develop severe intrahepatic cholestasis characterized by extensive bile duct proliferation, periductular fibrosis, and intrahepatic bile acid accumulation without developmental defects of bile duct morphology and infiltration of inflammatory cells. Ezrin is a membrane cytoskeletal cross-linker protein, which is known to interact with transporters, scaffold proteins, and actin cytoskeleton at the plasma membrane. We found that the normal apical membrane localizations of several transport proteins including cystic fibrosis transmembrane conductance regulator (CFTR), anion exchanger 2 (AE-2), aquaporin 1 (AQP1), and Na(+) /H(+) exchanger regulatory factor were disturbed in bile ducts of Vil2(kd/kd) mice. Stable expression of a dominant negative form of ezrin in immortalized mouse cholangiocytes also led to the reduction of the surface expression of CFTR, AE-2, and AQP1. Reduced surface expression of these transport proteins was accompanied by reduced functional expression, as evidenced by the fact these cells exhibited decreased CFTR-mediated Cl(-) efflux activity. Furthermore, bile flow and biliary HCO3 (-) concentration were also significantly reduced in Vil2(kd/kd) mice.

CONCLUSION

Dysfunction of ezrin mimics important aspects of the pathological mechanisms responsible for cholangiopathies. The Vil2(kd/kd) mouse may be a useful model to exploit in the development and testing of potential therapies for cholangiopathies.

Impact of transjugular intrahepatic portosystemic shunt on post-colectomy complications in patients with ulcerative colitis and primary sclerosing cholangitis

Objective: Primary sclerosing cholangitis (PSC) occurs in approximately 5% of patients with ulcerative colitis (UC). The risk of colon cancer is higher in patients undergoing colectomy, who have simultaneous PSC & UC. Our aim was to study the impact, in terms of post-colectomy survival and complications, of transjugular intrahepatic portosystemic shunt (TIPS) before colectomy in these patients.

Methods: In this retrospective, case-control study, information was obtained on demographics, disease characteristics, TIPS characteristics, and post-colectomy complications. Nine patients with PSC and UC who underwent TIPS prior to colectomy (the Study group) and 37 patients with PSC and UC who underwent only colectomy without TIPS (the Control group) were included. Either an analysis of variance or the non-parametric Kruskal-Wallis test were used for continuous variables and Fisher’s Exact test or Pearson’s chi-squared test was used for categorical factors.

Results: There was no difference in the mean age between the two groups; however patients in the Study group had lower platelet count (P = 0.005) as well as higher Model for End- Stage Liver disease (MELD) scores (P < 0.001). Also, patients in the Study group had increased PSC severity as determined by Mayo PSC Risk Scores (1.50 vs. 0.20) (P = 0.001). Total bilirubin levels were higher in the Study group (2.3 vs. 0.8 mg/dL) (P = 0.011). Comparing the post-operative complication rates without adjusting for disease severity, the Study group had more wound infections (P = 0.034), more wound dehiscence (P = 0.022), and a higher re-admission rate within 30 days (P = 0.032); however, the post-operative mortality was not significantly different.

Conclusion: Patients with PSC and UC who underwent TIPS prior to colectomy had higher rates of complications; however, this was probably due to the greater severity of cirrhosis and PSC in this population.

The Fas/Fas ligand apoptosis pathway underlies immunomodulatory properties of human biliary tree stem/progenitor cells

BACKGROUND & AIMS

Human biliary tree stem/progenitor cells (hBTSCs) are multipotent epithelial stem cells, easily obtained from the biliary tree, with the potential for regenerative medicine in liver, biliary tree, and pancreas diseases. Recent reports indicate that human mesenchymal stem cells are able to modulate the T cell immune response. However, no information exists on the capabilities of hBTSCs to control the allogeneic response. The aims of this study were to evaluate FasL expression in hBTSCs, to study the in vitro interaction between hBTSCs and human lymphocytes, and the role of Fas/FasL modulation in inducing T cell apoptosis in hBTSCs/T cell co-cultures.

METHODS

Fas and FasL expression were evaluated in situ and in vitro by immunofluorescence and western blotting. Co-cultures of hBTSCs with human leukocytes were used to analyze the influence of hBTSCs on lymphocytes activation and apoptosis.

RESULTS

hBTSCs expressed HLA antigens and FasL in situ and in vitro. Western blot data demonstrated that hBTSCs constitutively expressed high levels of FasL that increased after co-culture with T cells. Confocal microscopy demonstrated that FasL expression was restricted to EpCAM(+)/LGR5(+) cells. FACS analysis of T cells co-cultured with hBTSCs indicated that hBTSCs were able to induce apoptosis in activated CD4(+) and CD8(+) T cell populations. Moreover, the Fas receptor appears to be more expressed in T cells co-cultured with hBTSCs than in resting T cells.

CONCLUSIONS

Our data suggest that hBTSCs could modulate the T cell response through the production of FasL, which influences the lymphocyte Fas/FasL pathway by inducing "premature" apoptosis in CD4(+) and CD8(+) T cells.

Risk factors and outcome in patients with primary sclerosing cholangitis with persistent biliary candidiasis

Background

Candidiasis is commonly observed in patients with primary sclerosing cholangitis (PSC), but the clinical risk factors associated with its presence have not been fully investigated. In this study, we aimed to analyse the incidence, risk factors, and transplantation-free survival in primary sclerosing cholangitis (PSC) patients with persistent biliary candidiasis.

Methods

We retrospectively analysed patients diagnosed with PSC who were admitted to our department during 2002 to 2012. One-hundred fifty patients whose bile cultures were tested for fungal species were selected, and their clinical and laboratory parameters were investigated. The results of endoscopic retrograde cholangiography (ERC) and bile cultures were analysed using chart reviews. The cases of biliary candidiasis were sub-classified as transient or persistent.

Results

Thirty out of 150 (20.0%) patients had biliary candidiasis. Although all patients demonstrated comparable baseline characteristics, those with biliary candidiasis showed significantly reduced transplantation-free survival (p < 0.0001) along with a markedly elevated frequency of cholangiocarcinoma (CCA) (p = 0.04). The patients were further sub-classified according to the transient (15/30) or persistent (15/30) nature of their biliary candidiasis. A subgroup analysis showed reduced survival with a greater necessity for orthotopic liver transplantation (OLT) only in patients with persistence of Candida (p = 0.007). The survival in the patients with transient biliary candidiasis was comparable to that in candidiasis-free patients. In a multivariate regression analysis that included Mayo risk score (MRS), sex, age, dominant stenosis, inflammatory bowel disease, autoimmune hepatitis overlap syndrome, and number of times ERC was performed, biliary candidiasis was an independent risk factor for reduced survival (p = 0.008). Risk factors associated with acquisition of biliary candidiasis were age at PSC diagnosis and number of ERCs.

Conclusions

The persistence of biliary candidiasis is associated with markedly reduced transplantation-free survival in PSC patients. By contrast, actuarial survival in patients with transient biliary candidiasis approaches that for patients without any evidence of biliary candidiasis. Further studies on the treatment of persistent biliary candidiasis in patients with PSC are warranted.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-014-0562-8) contains supplementary material, which is available to authorized users.

Variant adiponutrin confers genetic protection against cholestatic itch

Lysophosphatidic acid (LPA) mediates cholestatic pruritus. Recently the enzyme PNPLA3, expressed in liver and skin, was demonstrated to metabolise LPA. Here we assess the association of the PNPLA3 variant p.Ile148Met, known to be associated with (non-)alcoholic fatty liver disease (NAFLD) in genome-wide association studies, with cholestatic itch in 187 patients with primary biliary cirrhosis (PBC) and 250 PBC-free controls as well as 201 women with intrahepatic cholestasis of pregnancy (ICP) and 198 female controls without a history of ICP. Our hypothesis was that the intensity of cholestatic itch differs in carriers of distinct PNPLA3 p.Ile148Met genotypes. Patients with PBC carrying the allele p.148Met that confers an increased NAFLD risk reported less itching than carriers of the p.148Ile allele (ANOVA P = 0.048). The PNPLA3 p.148Ile allele increased the odds of requiring plasmapheresis for refractory pruritus (OR = 3.94, 95% CI = 0.91–17.00, P = 0.048). In line with these findings, the PNPLA3 p.148Met allele was underrepresented in the ICP cohort (OR = 0.66, 95% CI = 0.47–0.92, P = 0.013). Notwithstanding the need for further replication of these findings, we conclude that the PNPLA3 allele p.148Met might confer protection against cholestatic pruritus, possibly due to increased LPA-acyltransferase activity in liver and/or skin.

Therapeutic role of bile acids and nuclear receptor agonists in fibrosing cholangiopathies

Chronic inflammatory bile duct diseases such as primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) result in progressive fibrosis of the biliary tract and ultimately cirrhosis of the liver. Since the etiology and pathogenesis of these fibrosing cholangiopathies are still poorly understood, therapeutic options are rather limited at present. Ursodeoxycholic acid (UDCA) is the paradigm therapeutic bile acid and established standard treatment for PBC, but its role for medical therapy of PSC is still under debate. Promising novel bile acid-based therapeutic options include 24-norursodeoxycholic acid, a side chain-shortened C23 homologue of UDCA, and bile acid receptor/farnesoid X receptor agonists (e.g., obeticholic acid) which currently undergo clinical development for fibrosing cholangiopathies such as PBC and PSC. Other nuclear receptors such as vitamin D receptor and fatty acid-activated peroxisome proliferator-activated receptors are also of considerable interest. This review article is a summary of an overview talk given at Falk Symposium 191 on Advances in Pathogenesis and Treatment of Liver Diseases held in London, October 3-4, 2013, and summarizes the recent progress with novel therapeutic bile acids and bile acid derivatives as novel therapies for fibrosing cholangiopathies such as PBC and PSC.

Hepatobiliary manifestations of ulcerative colitis: an example of gut-liver crosstalk

The interaction between inflammatory bowel disease (IBD) and hepatobiliary manifestations represents a classic example of liver-gut crosstalk. The importance of liver-gut crosstalk in IBD is demonstrated in the pathogenesis and outcome of primary sclerosing cholangitis (PSC) in IBD patients. Immunoglobulin G4-associated cholangitis (IAC), which has recently been described in UC patients, may also illustrate the significance of gut-liver interaction in these patients. Presence of these hepatobiliary manifestations influences the outcome of associated IBD, in particular ulcerative colitis (UC), and vice versa. The pathogenesis of PSC is postulated to be related to gut inflammation in IBD that results in inflammation in the portal tracts (the 'leaky gut'). Enterohepatic circulation of lymphocytes from the gut to the liver is also of potential relevance to PSC pathogenesis and outcomes. The presence of PSC and gut inflammation in IBD influences the course and outcomes of both diseases. Further research is required, to understand the mutual effect of liver-gut crosstalk in the outcomes of UC patients, and highlights the importance of an interdisciplinary approach-involving gastroenterologists, hepatologists, advanced endoscopists and liver transplant surgeons-in the management of these patients.

Angiopoietin-2 and biliary diseases: elevated serum, but not bile levels are associated with cholangiocarcinoma

Background

The diagnosis of cholangiocarcinoma (CC) is challenging especially in patients with primary sclerosing cholangitis (PSC) and often delayed due to the lack of reliable markers. Angiopoietin-2 (Angpt-2) has been employed as a biomarker of angiogenesis and might be involved in tumor neoangiogenesis.

Aim

To evaluate the diagnostic potential of Angpt-2 as a biomarker to detect patients with CC.

Methods

Bile and serum Angpt-2 levels were measured in patients with CC (n = 45), PSC (n = 74), CC complicating PSC (CC/PSC) (n = 11) and patients with bile duct stones (n = 37) in a cross sectional study. Diagnostic accuracy of Angpt-2 was compared to carbohydrate antigen 19-9 (CA19-9). Fluorescent immunohistochemistry from human CC liver tissue samples was performed to localize the origin of Angpt-2.

Results

Serum Angpt-2 concentration was significantly elevated in patients with CC compared to control patients (p<0.05). Diagnostic accuracy of Angpt-2 as determined by receiver operating characteristic (ROC) analysis resulted in a higher area under the curve (AUC) value compared to CA19-9 (AUC: 0.85 versus 0.77; 95% confidence interval (CI): 0.74–0.93 versus 0.65–0.87, respectively). Angpt-2 was also detectable in bile, but was not associated with the presence of CC. Immunohistochemistry revealed a strong induction of Angpt-2 expression in the tumor vasculature.

Conclusions

Circulating Angpt-2 in serum might be a promising protein candidate locally derived from the tumor vasculature in patients with CC. Measurement of Angpt-2 in serum may be useful for diagnosis and further clinical management of patients with CC.

Review article: controversies in the management of primary biliary cirrhosis and primary sclerosing cholangitis

BACKGROUND

Despite considerable advances over the last two decades in the molecular understanding of cholestasis and cholestatic liver disease, little improvement has been made in diagnostic tools and therapeutic strategies.

AIMS

To critically review controversial aspects of the scientific basis for common clinical practice in primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) and to discuss key ongoing challenges to improve patient management.

METHODS

We performed a literature search using PubMed and by examining the reference lists of relevant review articles related to the clinical management of PBC and PSC. Articles were considered on the background of the European Association for the Study of the Liver (EASL) and the American Association for the Study of Liver Diseases (AASLD) practice guidelines and clinical experience of the authors.

RESULTS

Ongoing challenges in PBC mainly pertain to the improvement of medical therapy, particularly for patients with a suboptimal response to ursodeoxycholic acid. In PSC, development of medical therapies and sensitive screening protocols for cholangiocarcinoma represent areas of intense research. To rationally improve patient management, a better understanding of pathogenesis, including complications like pruritis and fatigue, is needed and there is a need to identify biomarker end-points for treatment effect and prognosis. Timing of liver transplantation and determining optimal regimens of immunosuppression post-liver transplantation will also benefit from better appreciation of pre-transplant disease mechanisms.

CONCLUSION

Controversies in the management of PBC and PSC relate to topics where evidence for current practice is weak and further research is needed.

Nationwide survey for primary sclerosing cholangitis and IgG4-related sclerosing cholangitis in Japan

BACKGROUND

We previously conducted nationwide surveys for primary sclerosing cholangitis (PSC) in Japan, and demonstrated several characteristic features of Japanese PSC patients, yet patients with IgG4-related sclerosing cholangitis (IgG4-SC) might be misdiagnosed as PSC. Since the clinical diagnostic criteria of IgG4-SC were established in 2012, we again conducted a nationwide survey to investigate the characteristics of PSC and IgG4-SC lacking pancreatic involvement.

METHODS

The design was a questionnaire-based, multi-center retrospective study. The enrolled subjects were patients with PSC and IgG4-SC without pancreatic involvement diagnosed after 2005.

RESULTS

We enrolled 197 PSC and 43 IgG4-SC patients without pancreatic lesions. The male dominance was significantly evident in IgG4-SC (P = 0.006). In patients with PSC, two peaks in age distribution were clearly observed. IgG4-SC was not detected in any patient younger than 45 years of age. At presentation, serum albumin and IgM were significantly higher in PSC, while serum IgG and IgG4 were significantly elevated in IgG4-SC. Inflammatory bowel disease (IBD) was detected in only 68/197 PSC patients (34%). The prognosis of IgG4-SC was considerably better than that of PSC.

CONCLUSION

We confirmed several interesting clinical details of PSC in Japanese patients: two peaks in the age distribution and lower prevalence of IBD.

Chronic ulcerative colitis and colorectal cancer

One of the most important consequences of chronically active ulcerative colitis (UC) or Crohn's disease (CD) - the two major forms of inflammatory bowel disease (IBD) - is the development of colorectal cancer (CRC). An increased risk for the occurrence of CRC in up to 30% of affected patients after 35years of UC has been reported. Recent evidence from population based studies indicates a lower risk. Nevertheless the incidence is still significantly increased as compared to individuals without chronic colitis. Colitis-associated CRC (CAC) does not display the adenoma-carcinoma sequence which is typical for sporadic CRC and the pathophysiology appears to be different. Chronic inflammation and the increased turnover of epithelial cells contribute to the development of low- and high-grade dysplasia which may further transform into CAC. Reactive oxygen species (ROS) generated by the inflammatory infiltrate are thought to contribute to the generation of dysplastic lesions. In sporadic CRC the sequence of mutations that finally lead to malignancy involves early activation of Wnt/β-catenin pathway (in 90% of cases) including mutations in adenomatous polyposis coli (APC) tumor suppressor gene, its regulating kinase GSK3β and β-catenin itself. β-catenin mutations are rarer in CAC and mutations in APC occur rather late during the disease progression, whereas there are earlier mutations in p53 and K-ras. Recent data indicate that the intestinal microbiome and its interaction with a functionally impaired mucosal barrier may also play a role in CAC development. CACs frequently show aggressive growth and early metastases. The treatment of CAC in patients with colitis always includes proctocolectomy with ileoanal anastomosis as meta- or synchronic lesions are frequent.

Liver abnormalities in bowel diseases

Liver abnormalities are often seen in bowel diseases. Whether these represent aspects of two separate diseases, or if one is causing the other, is not always easy to decide. Extraintestinal manifestations of inflammatory bowel disease (IBD) or coeliac disease are frequently observed. Of these extraintestinal manifestations, hepatic disorders are among the most common. Primary sclerosing cholangitis (PSC) and primary biliary cirrhosis are the most frequent hepatic disorders in IBD and coeliac disease, respectively. Genetic studies have lately elucidated the associations between IBD and PSC, but there is still a long way until we have complete understanding of the molecular aetiology and pathophysiology of these conditions. There is no curative treatment available for PSC, besides liver transplantation. Steatosis and cholelithiasis are also common in IBD, as are signs of hepatic injury due to IBD treatment. Less common liver abnormalities include liver abscesses, hepatic thromboembolic events, granulomatous liver disease and hepatic amyloidosis.