Changing nomenclature for PBC: from 'cirrhosis' to 'cholangitis'

Efficacy and Safety of Novel Oral Anti-Cholestatic Agents for Primary Biliary Cholangitis: Meta-Analyses and Systematic Review

Background: Primary biliary cholangitis (PBC) is a chronic autoimmune liver disease characterized by progressive bile duct damage and cholestasis. While ursodeoxycholic acid (UDCA) is the first-line therapy, approximately 40% of patients have incomplete responses, necessitating alternative treatments. This systematic review and meta-analysis evaluate the efficacy and safety of novel oral anti-cholestatic agents for PBC. Methods: A systematic literature search was conducted in electronic databases up to September 2024. Randomized controlled trials, cohort studies, and case-control studies evaluating novel oral anti-cholestatic agents in adult PBC patients were included. The primary outcome was a change in alkaline phosphatase (ALP) levels. Safety was assessed by the incidence of serious adverse events. Random-effect meta-analyses were performed. Results: Ten studies involving 878 patients were analyzed. Novel agents included seladelpar, fenofibrate, saroglitazar, bezafibrate, elafibranor, and budesonide. The meta-analysis showed significant reductions in ALP levels with novel agents compared to the controls (SMD -2.80; 95% CI -3.56, -2.03; p < 0.00001), with high heterogeneity (I2 = 93%). Saroglitazar achieved the largest effect size. There was no significant difference in serious adverse events between novel agents and controls (OR 1.21; 95% CI 0.81, 1.83; p = 0.35). Conclusions: Novel oral anti-cholestatic agents show promise in improving biochemical markers in PBC patients with suboptimal UDCA responses, with a safety profile comparable to controls. However, study heterogeneity and limited long-term data restrict direct comparisons. Larger standardized trials with extended follow-up are needed to confirm long-term efficacy and safety.

Risk of Coronary Artery Disease in Patients with Liver Cirrhosis: A Systematic Review and Meta-analysis

BACKGROUND AND AIMS

Coronary artery disease (CAD) is increasingly observed in patients with liver cirrhosis. However, data on the incidence and prevalence of CAD in cirrhotic patients are heterogeneous, and the association remains uncertain. In this study, we aimed to conduct a systematic review and meta-analysis to address these issues.

METHODS

PubMed, EMBASE, and Cochrane Library databases were searched. Incidence, prevalence, and factors associated with CAD were pooled using a random-effects model. Risk ratio (RR) and odds ratio (OR), with their 95% confidence interval (CI), were calculated to evaluate differences in CAD incidence and prevalence between patients with and without liver cirrhosis.

RESULTS

Fifty-one studies were included. The pooled incidences of CAD, acute coronary syndromes, and myocardial infarction (MI) were 2.28%, 2.02%, and 1.80%, respectively. Liver cirrhosis was not significantly associated with CAD incidence (RR = 0.77; 95% CI = 0.46-1.28) or MI (RR = 0.87; 95% CI = 0.49-1.57). The pooled prevalence of CAD, acute coronary syndromes, and MI was 18.87%, 12.54%, and 6.12%, respectively. Liver cirrhosis was not significantly associated with CAD prevalence (OR = 1.29; 95% CI = 0.83-2.01) or MI (OR = 0.58; 95% CI = 0.28-1.22). Non-alcoholic steatohepatitis, hepatitis C virus, advanced age, male sex, diabetes mellitus, hypertension, hyperlipidemia, smoking history, and family history of CAD were significantly associated with CAD in cirrhotic patients.

CONCLUSIONS

CAD is common in cirrhotic patients, but cirrhosis itself may not be associated with an increased CAD risk. In addition to traditional risk factors, non-alcoholic steatohepatitis and hepatitis C virus infection are also associated with CAD presence in cirrhotic patients.

Primary biliary cholangitis drug evaluation and regulatory approval: Where do we go from here?

Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease. The management landscape was transformed 20 years ago with the advent of ursodeoxycholic acid. Up to 40% of patients do not, however, respond adequately to ursodeoxycholic acid and therefore still remain at risk of disease progression to cirrhosis. The introduction of obeticholic acid as a second-line therapy for patients failing ursodeoxycholic acid has improved outcomes for patients with PBC. There remains, however, a need for better treatment for patients at higher risk. The greatest threat facing our efforts to improve treatment in PBC is, paradoxically, the regulatory approval model providing conditional marketing authorization for new drugs based on biochemical markers on the condition that long-term, randomized placebo-controlled outcome trials are performed to confirm efficacy. As demonstrated by the COBALT confirmatory study with obeticholic acid, it is difficult to retain patients in the required follow-on confirmatory placebo-controlled PBC outcome trials when a licensed drug is commercially available. New PBC therapies in development, such as the peroxisome proliferator-activated receptor agonists, face even greater challenges in demonstrating outcome benefit through randomized placebo-controlled studies once following conditional marketing authorization, as there will be even more treatment options available. A recently published EMA Reflection Paper provides some guidance on the regulatory pathway to full approval but fails to recognize the importance of real-world data in providing evidence of outcome benefit in rare diseases. Here we explore the impact of the EMA reflection paper on PBC therapy and offer pragmatic solutions for generating evidence of long-term outcomes through real-world data collection.

The latest research trends in primary biliary cholangitis: a bibliometric analysis

The bibliometric analysis uses the citation count of an article to measure its impact in the scientific community, but no study has been undertaken to determine the most influential papers in the field of primary biliary cholangitis (PBC). This study aimed to investigate the global research interest regarding PBC in dentistry using a bibliometric approach. We searched the Web of Science Core Collection database to find the top 100 most cited (T100) articles focusing on PBC. The information about each article including citations, authors, journals, countries, institutions, and keywords was recorded for bibliometric analysis. The T100 articles related to PBC were published from 1983 to 2019 and were originated from 26 countries. A total of 805 different authors were from 342 different institutions, and articles written by them were published in 35 journals. The five most frequently occurring keywords were "biochemical response," "ursodeoxycholic acid," "primary biliary cirrhosis," "antimitochondrial antibody," and "autoimmunity." The T100 articles were classified into different research focuses: pathogenesis (41%), treatment (20%), prognosis (12%), epidemiology (9%), diagnosis (8%), and others (10%). These 100 articles included 32 observational studies, 29 basic research articles, 15 reviews, eight meta-analyses, 12 clinical trials, and four clinical guidelines. The 100 top-cited articles are marked with the leading countries, institutions, journals, hotspots, and development trends in the PBC field that could provide the foundation for further investigations.

Gender-specific development of experimental autoimmune cholangitis induced by double-stranded RNA

Here we investigated the gender difference in murine cholangitis resembling human primary biliary cholangitis (PBC) caused by synthetic double-stranded RNA, and underlying hepatic innate immune responses. Female C57Bl/6 mice given repeated injections of polyinosinic-polycytidylic acid (poly I:C) for 24 weeks developed overt cholangitis with positive serum anti-mitochondria-M2 antibody, whereas male mice showed minimal pathological changes without induction in autoantibody. Poly I:C induced hepatic inflammatory cytokines and type-I interferons predominantly in females. Hepatic expression levels of toll-like receptor (TLR) 3 and melanoma differentiation-associated protein (MDA) 5 were equivalent in both genders; however, both mRNA and protein levels of retinoic acid-inducible gene (RIG)-I were nearly doubled in female livers. Following 4-week injections of poly I:C, not only hepatic RIG-I, but also TLR3 and MDA5 showed female-predominance. Moreover, hepatic RIG-I levels were 25% lower in ovariectomized mice, whereas supplementation of 17 β-estradiol enhanced hepatic RIG-I expression, as well as cytokine induction. These results clearly indicate that hepatic RIG-I expression is potentiated by estrogen, and triggers gender-dependent hepatic innate immune response against double-stranded RNA, which most likely play a pivotal role in the pathogenesis of autoimmune cholangiopathies including PBC.

Definite and indeterminate nonalcoholic steatohepatitis share similar clinical features and prognosis: A longitudinal study of 1893 biopsy-proven nonalcoholic fatty liver disease subjects

BACKGROUND AND AIM

Histological score systems may not fully capture the essential nonalcoholic steatohepatitis (NASH) features, which is one of the leading causes of screening failure in clinical trials. We assessed the NASH distribution and its components across the fibrosis stages and their impact on the prognosis and their relationship with the concept of metabolic-associated fatty liver disease (MAFLD).

METHODS

Spanish multicenter study including 1893 biopsy-proven nonalcoholic fatty liver disease (NAFLD) patients from HEPAmet registry. NASH was diagnosed by NAS score ≥4 (including steatosis, ballooning and lobular inflammation) and fibrosis by Kleiner score. The presence of MAFLD was determined. Progression to cirrhosis, first episode of decompensated cirrhosis and death were collected during the follow-up (4.7 ± 3.8 years).

RESULTS

Fibrosis was F0 34.3% (649/1893), F1 27% (511/1893), F2 16.5% (312/1893), F3 15% (284/1893) and F4 7.2% (137/1893). NASH diagnosis 51.9% (982/1893), and its individual components (severe steatosis, ballooning and lobular inflammation), increased from F0 (33.6%) to F2 (68.6%), and decreased significantly in F4 patients (51.8%) (P = .0001). More than 70% of non-NASH patients showed some inflammatory activity (ballooning or lobular inflammation), showing a similar MAFLD rate than NASH (96.2% [945/982] vs. 95.2% [535/562]) and significantly higher than nonalcoholic fatty liver (NAFL) subjects (89.1% [311/349]) (P < .0001). Progression to cirrhosis was similar between NASH (9.5% [51/539]) and indeterminate NASH (7.9% [25/316]), and higher than steatosis (5% [14/263]) (logRank 8.417; P = .015). Death and decompensated cirrhosis were similar between these.

CONCLUSIONS

The prevalence of steatohepatitis decreased in advanced liver disease. However, most of these patients showed some inflammatory activity histologically and had metabolic disturbances. These findings should be considered in clinical trials whose main aim is to prevent cirrhosis progression and complications, liver transplant and death.

Fibrotic Events in the Progression of Cholestatic Liver Disease

Cholestatic liver diseases including primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are associated with active hepatic fibrogenesis, which can ultimately lead to the development of cirrhosis. However, the exact relationship between the development of liver fibrosis and the progression of cholestatic liver disease remains elusive. Periductular fibroblasts located around the bile ducts seem biologically different from hepatic stellate cells (HSCs). The fibrotic events in these clinical conditions appear to be related to complex crosstalk between immune/inflammatory mechanisms, cytokine signalling, and perturbed homeostasis between cholangiocytes and mesenchymal cells. Several animal models including bile duct ligation (BDL) and the Mdr2-knockout mice have improved our understanding of mechanisms underlying chronic cholestasis. In the present review, we aim to elucidate the mechanisms of fibrosis in order to help to identify potential diagnostic and therapeutic targets.

Current understanding of primary biliary cholangitis

Primary biliary cholangitis (PBC) causes chronic and persistent cholestasis in the liver, eventually resulting in cirrhosis and hepatic failure without appropriate treatment. PBC mainly develops in middle-aged women, but it is also common in young women and men. PBC is considered a model of autoimmune disease because of the presence of disease-specific autoantibodies, that is, antimitochondrial antibodies (AMAs), intense infiltration of mononuclear cells into the bile ducts, and a high prevalence of autoimmune diseases such as comorbidities. Histologically, PBC is characterized by degeneration and necrosis of intrahepatic biliary epithelial cells surrounded by a dense infiltration of mononuclear cells, coined as chronic non-suppurative destructive cholangitis, which leads to destructive changes and the disappearance of small- or medium-sized bile ducts. Since 1990, early diagnosis with the detection of AMAs and introduction of ursodeoxycholic acid as first-line treatment has greatly altered the clinical course of PBC, and liver transplantation-free survival of patients with PBC is now comparable to that of the general population.

Non-neoplastic cholangiopathies: an algorithmic approach

Cholangiopathies are chronic diseases that affect the bile ducts, comprising a heterogeneous group of progressive and potentially fatal entities. The diagnosis of these diseases is a great challenge for radiologists because of the overlapping of their clinical, biochemical, and imaging findings. Nevertheless, identifying the precise etiology is crucial, given that the therapeutic options are distinct and influence the prognosis of the patient. The purpose of this review article is to discuss some of the non-neoplastic causes of cholangiopathies and to provide a useful diagnostic algorithm.

MAFLD: A Consensus-Driven Proposed Nomenclature for Metabolic Associated Fatty Liver Disease

Fatty liver associated with metabolic dysfunction is common, affects a quarter of the population, and has no approved drug therapy. Although pharmacotherapies are in development, response rates appear modest. The heterogeneous pathogenesis of metabolic fatty liver diseases and inaccuracies in terminology and definitions necessitate a reappraisal of nomenclature to inform clinical trial design and drug development. A group of experts sought to integrate current understanding of patient heterogeneity captured under the acronym nonalcoholic fatty liver disease (NAFLD) and provide suggestions on terminology that more accurately reflects pathogenesis and can help in patient stratification for management. Experts reached consensus that NAFLD does not reflect current knowledge, and metabolic (dysfunction) associated fatty liver disease "MAFLD" was suggested as a more appropriate overarching term. This opens the door for efforts from the research community to update the nomenclature and subphenotype the disease to accelerate the translational path to new treatments.

TianJiu therapy for α-naphthyl isothiocyanate-induced intrahepatic cholestasis in rats treated with fresh Ranunculus sceleratus L

ETHNOPHARMACOLOGICAL RELEVANCE

TianJiu (TJ) therapy, one type of cold moxibustion, applies to specific acupuncture points with herbal patches of hot nature, providing a constant irritant to the skin until the presence of hyperemia and blistering. Traditional and clinical reports suggest that TJ is an effective therapy for the treatment of jaundice with fresh Ranunculus sceleratus L. (RS), in which protoanemonin is one of the main irritant constituents. However, the therapeutic effect of TJ treatment with fresh RS against intrahepatic cholestasis has not been studied in animal experiments.

AIM OF THE STUDY

Present study was undertaken to investigate the effect of TJ treatment with fresh RS against intrahepatic cholestasis in rats and provide an experimental basis for the underlying mechanism of TJ therapy.

MATERIALS AND METHODS

Male intrahepatic cholestatic Sprague-Dawley rats induced by 2% α-naphthylisothiocyanate (ANIT, 80 mg/kg B.W.) were treated by TJ therapy with fresh RS. The levels of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), direct bilirubin (DBIL), total bilirubin (TBIL), total bile acid (TBA), hepatic malondialdehyde (MDA) and nitric monoxide (NO), as well as hepatic body ratio, bile flow and hepatic histopathological assay were measured and evaluated to investigate the therapeutic effect of TJ treatment with fresh RS. Phytochemical analysis of fresh and dried RS was performed by gas chromatography-mass spectrometer (GC-MS).

RESULTS

After TJ treatment with fresh RS, the abnormally elevated levels of serum AST, ALT, ALP, DBIL, TBIL and TBA, as well as hepatic MDA and NO at 108 h were reduced significantly (versus model group, P < 0.01). The hepatic body ratio, bile flow and hepatic pathological change of cholestatic rats at 108 h in TJ group were restored when compared with those of model group. Thirty-one compounds including lactones, flavonoids and phenolic acids were identified and determined by GC-MS analysis. The content of protoanemonin in fresh RS (9.49%) was about 25-fold higher than that in dried RS (0.38%).

CONCLUSIONS

TJ treatment with fresh RS exhibited good therapeutic effect on ANIT-induced intrahepatic cholestasis in rats, which may be due to the attenuated oxidative stress in the liver tissue. It is rational for the ancients to choose fresh RS as TJ herbal patches because of its abundant protoanemonin with the character of irritant. The qualitative and quantitative results of GC-MS analysis provided the chemical basis of TJ therapy with fresh RS, which can be regarded as a simple and efficient method for the treatment of cholestasis hepatitis.

Recurrence of disease following organ transplantation in autoimmune liver disease and systemic lupus erythematosus

Disease recurrence after organ transplantation associated with graft failure is a major clinical challenge in autoimmune diseases. Primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC) and autoimmune Hepatitis (AIH) are the three most common (autoimmune liver diseases) ALD for which liver transplantation (LT) is the most effective treatment option for patients with end-stage diseases. Although the 5- and 10-year survival rates of post-LT patients are remarkable (80-84% and 71-79% in PBC, 73-87% and 58-83% in PSC, 76-79% and 67-77% respectively in AIH patients), post-LT disease recurrence is not uncommon. Here, we summarize literature findings on disease recurrence of these ALD with emphasis on the incidence, risk factors and impact on long-term outcome. We noted that the incidence of disease recurrence varies between studies, which ranges from 53% to 10.9% in PBC, 8.2% to 44.7% in PSC and 7% to 42% in AIH. The variations are likely due to differences in study design, such as sample size, duration of studies and follow up time. This is further compounded by the lack of precise clinical diagnosis criteria and biomarkers of disease recurrence in these ALD, variation in post-LT treatment protocols to prevent disease recurrence and a multitude of risk factors associated with these ALD. While recurrence of PBC and AIH does not significantly impact long term outcome including overall survival, recurrent PSC patients often require another LT. Renal transplantation, like LT, is the treatment of choice in patients with end-stage lupus nephritis. While calcineurin inhibitor (CNI) and immunosuppressive drugs have improved the survival rate, post-transplant recurrence of lupus nephritis from surveillance-biopsy proven lupus nephritis range from 30% to 44%. On the other hand, recurrence of post-transplant lupus nephritis from registry survey analysis were only 1.1% to 2.4%. In general, risk factors associated with an increased frequency of post-transplant recurrence of autoimmune diseases are not clearly defined. Large scale multi-center studies are needed to further define guidelines for the diagnosis and clinical management to minimize disease recurrence and improve outcomes of post-transplant patients.

Identification of clinical risk factors for histological progression of primary biliary cholangitis

AIM

To identify laboratory predictors of histological progression (HP) of primary biliary cholangitis (PBC).

METHODS

Sequential biopsies were carried out on 35 (11.4%) of 308 patients with PBC treated with ursodeoxycholic acid (UDCA). Patients were divided into high γ-glutamyl transpeptidase (GGT) (n = 18) and low GGT (n = 17) groups, based on the median value of GGT at baseline. Patients were then categorized as showing HP (progressive group, PG) or lacking HP (non-progressive group, NPG) according to the Scheuer and Nakanuma classifications, with the latter grading liver fibrosis (fibrosis score) and bile duct loss (BDL score).

RESULTS

According to the Scheuer definition, 12 patients had HP and 23 did not. According to the Nakanuma definition, 8 and 27 patients were in the PG and NPG groups, respectively. The fibrosis and BDL scores progressed in 13 and 8 patients, respectively, whereas 22 and 25 patients did not show HP, respectively. Fisher's exact probability test analysis revealed that the rate of HP using the Nakanuma fibrosis score was significantly higher in the high GGT group compared to the low GGT group (P < 0.05). However, no significant correlation was found between the HP of PBC and the biochemical response to UDCA therapy. Both univariate and multivariate logistic regression analyses indicated that the serum GGT level at baseline is an independent risk factor for an increased Nakanuma fibrosis score.

CONCLUSIONS

The level of serum GGT at baseline is significantly associated with liver fibrosis progression in PBC, and therefore could help to predict the HP of PBC.

The genetics of primary biliary cholangitis

PURPOSE OF REVIEW

Primary biliary cholangitis (PBC) is a female predominant chronic autoimmune disease of the intrahepatic bile ducts and with a long latent period. It is crucial to understand how genetics contribute to the disease.

RECENT FINDINGS

Geo-epidemiological studies in PBC have provided evidence of familial risk; case-control studies and genome wide association studies have identified various human leukocyte antigen (HLA) and non-HLA alleles that are associated with PBC. However, these alleles are non-PBC specific and most of the identified non-HLA loci were also found to be susceptible genes in other autoimmune diseases and different between study populations.

SUMMARY

Patients with PBC are often asymptomatic and often left undiagnosed. There are no known HLA and non-HLA alleles specific for PBC. Global effort and novel approaches such as epigenetics directed at identification of genetic risk factors will greatly facilitate accurate and timely diagnosis, which will improve prognosis and increase treatment options.

Editorial: liver transplantation for primary biliary cholangitis-the need for timely and more effective treatments

Linked Content

This article is linked to Harms et al and Harms et al papers. To view these articles, visit https://doi.org/10.1111/apt.15060 and https://doi.org/10.1111/apt.15118.

Anti-Ro60 Seropositivity Determines Anti-Ro52 Epitope Mapping in Patients With Systemic Sclerosis

Epitope mapping of anti-Ro52 antibodies (Abs) has been extensively studied in patients with Sjögren's syndrome (SjS) and systemic lupus erythematosus (SLE). Comprehensive epitope mapping in systemic sclerosis (SSc), where anti-Ro52 antibodies are also frequently detected, has not been performed. The aim of the present study was to fully characterize Ro52 epitopes in anti-Ro52-positive SSc using Ro52 fragments spanning the full antigen. Further analysis was made according to anti-Ro60 status. Epitope mapping was performed in 43 anti-Ro52-positive SSc patients. Seventy eight anti-Ro52-positive pathological controls, including 20 patients with SjS, 28 patients with SLE, 15 patients with dermatomyositis (DM), and 15 patients with primary biliary cholangitis (PBC), and 20 anti-Ro52-negative healthy individuals as normal controls were also tested. Five recombinant Ro52 fragments [Ro52-1 (aa 1-127), Ro52-2 (aa 125-268), Ro52-3 (aa 268-475), Ro52-4 (aa 57-180), and Ro52-5 (aa 181-320) were used to test reactivity by line-immunoassay and in house ELISA. Anti-Ro60 reactivity was tested by ELISA. All anti-Ro52 positive sera reacted with Ro52-2; none recognized Ro52-3. Antibodies against Ro52-1 were less frequently found in SSc than in SjS/SLE (11.6 vs. 41.7%, p = 0.001); and antibodies against Ro52-4 were less frequently found in SSc than in SjS/SLE (27.9 vs. 50%, p = 0.03). In SSc patients, reactivity against Ro52-1 was more frequent in anti-Ro52+/anti-Ro60+ than in anti-Ro52+/anti-Ro60-patients (33.3 vs. 0%, p = 0.003). In this comprehensive analysis of Ro52 epitope mapping in SSc, the coiled coil domain remains the predominant epitope on Ro52. Contrary to SjS and SLE, patients with SSc fail to identify epitopic regions within the N-terminus of the protein, especially if they lack con-current anti-Ro60 reactivity.

Primary biliary cholangitis: A tale of epigenetically-induced secretory failure?

Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease associated with autoimmune-related destruction of small to medium size intrahepatic bile ducts. The aetiology of PBC is unknown and its pathogenesis remains obscure. Both genetic variants and environmental factors have been linked to increased PBC susceptibility, with other alterations known to cooperate in disease pathobiology. Increasing evidence indicates the presence of epigenetic abnormalities in PBC, particularly alterations of cholangiocellular microRNAs (miRNAs or miRs). This review highlights and discusses the most relevant epigenetic alterations found in patients with PBC, focusing on the role of miR-506 in the promotion of cholestasis and immune activation.

Primary biliary cholangitis

Primary cholangitis (cirrhosis) is a chronic cholestatic disease with an unquestionable female predominance. It is characterised by inflammation of the small and medium size bile ducts, and can eventually progress to cirrhosis. Most patients remain asymptomatic and are diagnosed by the casual finding of an anicteric biochemical cholestasis with increased alkaline phosphatase. The pathogenesis is unknown and of presumed autoimmune origin in genetic susceptible subjects. M2-type antimitochondrial antibodies, and specific antinuclear antibodies (gp210 and Sp100) are typical and specific of the disease. The positivity of these antibodies and a biochemical cholestasis are sufficient for diagnosis, without the need for liver biopsy. Ursodeoxycholic acid is the specific treatment with an excellent response in more than 60% of patients. When this optimal response is not observed, it can be combined with new agents, but those that have shown to be effective are those that improve cholestasis such as fibrates and obeticholic acid.

Primary biliary cholangitis and bone disease

Osteoporosis, characterized by compromised bone strength leading to fragility fractures, is a common event in patients with primary biliary cholangitis (PBC). Osteomalacia, defined by poor bone mineralization is very uncommon. The pathogenesis of osteoporosis is not well clarified, but it mainly results from low bone formation. Few reports have revealed increased bone resorption, particularly in end-stage disease. The prevalence of osteoporosis is about 35% in the most significant studies, and it depends on the diagnostic criteria and severity of liver damage. Osteoporosis is associated with age, postmenopausal status, duration of PBC and advanced histological stage. Bone densitometry is the common method for the diagnosis of osteoporosis and should be performed in all patients with PBC. Lateral X-rays of the dorsal and lumbar spine should also be carried out to disclose vertebral fractures. There is no specific treatment but bisphosphonates, especially alendronate and ibandronate, efficiently increases bone mass and prevents bone loss. Despite these positive effects on bone mass no clear results on decreasing the fracture rate have been demonstrated, probably because the low number of patients included in the trials. The potential value of new agents requires further evaluation.

MicroRNA-506 promotes primary biliary cholangitis-like features in cholangiocytes and immune activation

Primary biliary cholangitis (PBC) is a chronic cholestatic liver disease associated with autoimmune phenomena targeting intrahepatic bile duct cells (cholangiocytes). Although its etiopathogenesis remains obscure, development of antimitochondrial autoantibodies against pyruvate dehydrogenase complex E2 is a common feature. MicroRNA (miR) dysregulation occurs in liver and immune cells of PBC patients, but its functional relevance is largely unknown. We previously reported that miR-506 is overexpressed in PBC cholangiocytes and directly targets both Cl- / HCO3- anion exchanger 2 and type III inositol 1,4,5-trisphosphate receptor, leading to cholestasis. Here, the regulation of miR-506 gene expression and its role in cholangiocyte pathophysiology and immune activation was studied. Several proinflammatory cytokines overexpressed in PBC livers (such as interleukin-8 [IL8], IL12, IL17, IL18, and tumor necrosis factor alpha) stimulated miR-506 promoter activity in human cholangiocytes, as revealed by luciferase reporter assays. Experimental overexpression of miR-506 in cholangiocytes dysregulated the cell proteomic profile (by mass spectrometry), affecting proteins involved in different biological processes including mitochondrial metabolism. In cholangiocytes, miR-506 (1) induced dedifferentiation with down-regulation of biliary and epithelial markers together with up-regulation of mesenchymal, proinflammatory, and profibrotic markers; (2) impaired cell proliferation and adhesion; (3) increased oxidative and endoplasmic reticulum stress; (4) caused DNA damage; and (5) sensitized to caspase-3-dependent apoptosis induced by cytotoxic bile acids. These events were also associated with impaired energy metabolism in mitochondria (proton leak and less adenosine triphosphate production) and pyruvate dehydrogenase complex E2 overexpression. Coculture of miR-506 overexpressing cholangiocytes with PBC immunocytes induced activation and proliferation of PBC immunocytes.

CONCLUSION

Different proinflammatory cytokines enhance the expression of miR-506 in biliary epithelial cells; miR-506 induces PBC-like features in cholangiocytes and promotes immune activation, representing a potential therapeutic target for PBC patients. (Hepatology 2018;67:1420-1440).

Access to care in rare liver diseases: New challenges and new opportunities

Patients with rare diseases are often disadvantaged, particularly those with rare liver diseases. Reasons for disadvantage include delayed or overlooked diagnosis, lack of local expertise and high-quality care, poor scientific understanding of the disease process and limited therapeutic options. In adult liver disease this can be compounded by prejudices towards patients with liver disease in general, because of a perception (incorrect for all rare liver diseases) that liver disease is lifestyle related and thus "self-inflicted". In paediatric rare liver diseases, such as biliary atresia, optimising outcomes requires a particularly timely diagnosis. Irrespective of patient age, the scientific and medical community must rise to the challenge of advancing our understanding of rare liver disease, searching for more effective and specific therapies, and providing the infrastructure to provide the best care for all patients, infants, children, young and older adults. The European Reference Network for Rare Liver Diseases is an important step in this direction.

Different effects of ursodeoxycholic acid on intrahepatic cholestasis in acute and recovery stages induced by alpha-naphthylisothiocyanate in mice

The aim of this study was to determine the effect of ursodeoxycholic acid (UDCA) on the alpha-naphthylisothiocyanate (ANIT)-induced acute and recovery stage of cholestasis model mice. In the acute stage of model mice, pretreatment with UDCA (25, 50, and 100 mg·kg^-1, ig) for 12 days prior to ANIT administration (50 mg·kg^-1, ig) resulted in the dramatic increase in serum biochemistry, with aggrevation of bile infarcts and hepatocyte necrosis. The elevation of beta-muricholic acid (β-MCA), cholic acid (CA), and taurocholic acid (TCA) in serum and liver, and reduction of these bile acids (BAs) in bile was observed. In contrast, in the recovery stage of model mice, treatment with UDCA (25, 50, and 100 mg·kg^-1, ig) for 7 days after ANIT administration (50 mg·kg^-1, ig) resulted in the significant decrease in levels of serum alanine aminotransferase (ALT) and total bile acid (TBA). Liver injury was attenuated, and the levels of TBA, CA, TCA, and β-MCA in the liver were significantly decreased. Additionally, UDCA can upregulate expression of BSEP, but it cannot upregulate expression of AE2. UDCA, which induced BSEP to increase bile acid-dependent bile flow, aggravated cholestasis and liver injury when the bile duct was obstructed in the acute stage of injury in model mice. In contrast, UDCA alleviated cholestasis and liver injury induced by ANIT when the obstruction was improved in the recovery stage.

Environmental basis of primary biliary cholangitis

Autoimmunity is a consequence of both genetic and environmental factors, occurring in genetically susceptible hosts with environmental triggers. While genome-wide association studies have revealed a number of susceptible genes contributing to etiology, the environmental triggers remain poorly understood. Primary biliary cholangitis, formally known as primary biliary cirrhosis, is considered a model autoimmune disease for which our group has extensively evaluated environmental factors involved in its etiology. Bacterial infection and xenobiotics have been proposed as candidate environmental factors that may explain tolerance breakdown and production of primary biliary cholangitis-specific antimitochondrial autoantibodies. Large-scale case-control studies have consistently detected an association of primary biliary cholangitis with urinary tract infections caused by Escherichia coli, as E. coli PDC-E2 is molecularly similar to human PDC-E2, the immunodominant target of AMAs. Another bacterium of interest is Novosphingobium aromaticivorans, a ubiquitous xenobiotic-metabolizing bacterium that produces lipoylated proteins, which are highly reactive with sera from primary biliary cholangitis patients. Regarding xenobiotics, case-control studies have suggested that frequent use of nail polish is associated with an increased susceptibility to primary biliary cholangitis. We found that 2-octynamide, the conjugate derived from 2-octynoic acid present in cosmetics, lipsticks, and some chewing gums, was unique in both its quantitative structure-activity relationship analysis and reactivity with primary biliary cholangitis sera. 2-nonyamide is another xenobiotic that also has the optimal chemical structure for xenobiotic modification of the PDC-E2 epitope, as demonstrated by the enhanced epitope recognition with AMA-positive PBC sera. Moreover, we found that C57BL/6 mice immunized with 2-octynoic acid-BSA possess many of the features characteristic to primary biliary cholangitis. Impact statement Autoimmunity is believed to develop in genetically susceptible hosts with triggers from the environment. Researchers have recently demonstrated that bacteria and xenobiotics commonly present in our environment are potential triggers of tolerance breakdown against autoantigens and autoimmunity, particularly in primary biliary cholangitis (PBC). The link between xenobiotics and PBC has been further confirmed with the establishment of PBC model mice by immunizing mice with xenobiotics.

Genetics and epigenetics in the pathogenesis of primary biliary cholangitis

Primary biliary cholangitis (PBC) is a chronic, slowly progressive cholestatic autoimmune liver disease predominantly afflicting women. PBC is characterized by the presence of disease-specific antimitochondrial antibodies and the histological destruction of intrahepatic bile ducts, which eventually lead to cirrhosis and hepatic failure. Fortunately, ursodeoxycholic acid therapy has improved the outcome of the vast majority of PBC cases. Although the etiology of PBC has not yet been elucidated, human leukocyte antigen (HLA) class II alleles have been consistently associated with disease onset for decades. PBC patients may also have genetically determined risk factors in non-HLA regions. Meanwhile, exposure to environmental factors, such as infectious diseases and harmful chemicals, can produce epigenetic alterations in some individuals and subsequent PBC onset. In this review, we describe the influence of HLA alleles and other gene polymorphisms on PBC along with the results of genome-wide association studies on this disease and its future prospects in terms of epigenetics.

Novel strategies and therapeutic options for the management of primary biliary cholangitis

Primary biliary cholangitis (PBC) is a chronic autoimmune liver disease. It has a varied course of progression ranging from being completely asymptomatic to aggressive disease leading to cirrhosis and resulting in liver transplantation. In addition, symptoms can be debilitating and can have a major impact on quality of life. For decades, there was only one anti-cholestatic agent available to target this disease and that was only effective in around half of patients, with little or no effect on symptoms. With increasing understanding of the pathogenic mechanisms of PBC and potential targets for drug treatment, pharmaceutical companies have shown a greater interest in this rare disease. A large number of novel therapeutic molecules have been developed and are currently being evaluated. In this review article all the novel molecules in use and in trials targeting cholestasis and symptoms in PBC are discussed.

Clinical implications of antimitochondrial antibody seropositivity in autoimmune hepatitis: a multicentre study

BACKGROUND/AIM

Antimitochondrial antibody (AMA) positivity is the serological marker of primary biliary cholangitis (PBC), but can also be sporadically detected in autoimmune hepatitis (AIH). Little is known about the clinical significance of AMA in AIH.

PATIENTS AND METHODS

We recruited 47 AMA-positive AIH cases from several centres and compared them with 264 well-characterized Italian AIH patients. Cases with any features of PBC were excluded.

RESULTS

In univariate analysis, AMA-positive AIH patients were older (46 vs. 36, P=0.002) and more responsive to immunosuppression (74 vs. 59%, P=0.05), but no differences were observed between the two groups after logistic regression using AMA as a dependent variable. None of the AMA-positive AIH patients showed signs of evolving PBC features after a median follow-up of up 47 months. AMA was detected in combination with all serological AIH markers except antiliver kidney microsome type 1 and antiliver cytosol type 1. AMA was the only marker of autoimmunity in eight cases.

CONCLUSION

We found no differences between AIH with and without AMA. The groups had similar clinical, biochemical and histological features. AMA-positive AIH patients did not evolve towards PBC. In some cases, AMA was the only autoantibody.

Obeticholic acid, a selective farnesoid X receptor agonist, regulates bile acid homeostasis in sandwich-cultured human hepatocytes

Farnesoid X receptor (FXR) is a master regulator of bile acid homeostasis through transcriptional regulation of genes involved in bile acid synthesis and cellular membrane transport. Impairment of bile acid efflux due to cholangiopathies results in chronic cholestasis leading to abnormal elevation of intrahepatic and systemic bile acid levels. Obeticholic acid (OCA) is a potent and selective FXR agonist that is 100‐fold more potent than the endogenous ligand chenodeoxycholic acid (CDCA). The effects of OCA on genes involved in bile acid homeostasis were investigated using sandwich‐cultured human hepatocytes. Gene expression was determined by measuring mRNA levels. OCA dose‐dependently increased fibroblast growth factor‐19 (FGF‐19) and small heterodimer partner (SHP) which, in turn, suppress mRNA levels of cholesterol 7‐alpha‐hydroxylase (CYP7A1), the rate‐limiting enzyme for de novo synthesis of bile acids. Consistent with CYP7A1 suppression, total bile acid content was decreased by OCA (1 μmol/L) to 42.7 ± 20.5% relative to control. In addition to suppressing de novo bile acids synthesis, OCA significantly increased the mRNA levels of transporters involved in bile acid homeostasis. The bile salt excretory pump (BSEP), a canalicular efflux transporter, increased by 6.4 ± 0.8‐fold, and the basolateral efflux heterodimer transporters, organic solute transporter α (OST_α) and OST_β increased by 6.4 ± 0.2‐fold and 42.9 ± 7.9‐fold, respectively. The upregulation of BSEP and OST_α and OST_β, by OCA reduced the intracellular concentrations of d₈‐TCA, a model bile acid, to 39.6 ± 8.9% relative to control. These data demonstrate that OCA does suppress bile acid synthesis and reduce hepatocellular bile acid levels, supporting the use of OCA to treat bile acid‐induced toxicity observed in cholestatic diseases.

The fingerprint of antimitochondrial antibodies and the etiology of primary biliary cholangitis

The identification of environmental factors that lead to loss of tolerance has been coined the holy grail of autoimmunity. Our work has focused on the reactivity of antimitochondrial autoantibodies (AMA) to chemical xenobiotics and has hypothesized that a modified peptide within PDC-E2, the major mitochondrial autoantigen, will have been immunologically recognized at the time of loss of tolerance. Herein, we successfully applied intein technology to construct a PDC-E2 protein fragment containing amino acid residues 177-314 of PDC-E2 by joining a recombinant peptide spanning residues 177-252 (PDC-228) with a 62-residue synthetic peptide from 253 to 314 (PP), which encompasses PDC-E2 inner lipoyl domain (ILD). We named this intein-constructed fragment PPL. Importantly, PPL, as well as lipoic acid conjugated PPL (LA-PPL) and xenobiotic 2-octynoic acid conjugated PPL (2OA-PPL), are recognized by AMA. Of great importance, AMA has specificity for the 2OA-modified PDC-E2 ILD peptide backbone distinct from antibodies that react with native lipoylated PDC-E2 peptide. Interestingly, this unique AMA subfraction is of the immunoglobulin M isotype and more dominant in early-stage primary biliary cholangitis (PBC), suggesting that exposure to 2OA-PPL-like compounds occurs early in the generation of AMA. To understand the structural basis of this differential recognition, we analyzed PPL, LA-PPL, and 2OA-PPL using electron paramagnetic resonance spectroscopy, with confirmations by enzyme-linked immunosorbent assay, immunoblotting, and affinity antibody analysis. We demonstrate that the conformation of PDC-E2 ILD is altered when conjugated with 2OA, compared to conjugation with lipoic acid.

CONCLUSION

A molecular understanding of the conformation of xenobiotic-modified PDC-E2 is critical for understanding xenobiotic modification and loss of tolerance in PBC with widespread implications for a role of environmental chemicals in the induction of autoimmunity. (Hepatology 2017;65:1670-1682).

Recurrence of primary sclerosing cholangitis, primary biliary cholangitis and auto-immune hepatitis after liver transplantation

Liver transplantation is a well-accepted treatment for decompensated chronic liver disease due to primary sclerosing cholangitis (PSC), primary biliary cholangitis (PBC) and auto-immune hepatitis (AIH). Survival after liver transplantation is generally good with 1 and 5-year survival rates around 90% and 70-85%. After transplantation, however, these diseases recur in 8.6-27% (rPSC), 10.9-42.3% (rPBC) and 7-42% (rAIH), and this poses significant challenges in terms of management and graft outcome in these patients. In this review we discuss the incidence, clinical presentation, challenges in diagnosis, reported risk factors and impact on post-transplant outcomes of recurrence of PSC, PBC and AIH after liver transplantation. We also discuss some of the limitations of current investigations and formulate idea's for future research objectives.

Genetic Contribution to the Pathogenesis of Primary Biliary Cholangitis

Formerly termed primary biliary cirrhosis, primary biliary cholangitis (PBC) is a chronic and progressive cholestatic liver disease characterized by the presence of antimitochondrial antibodies. Ursodeoxycholic acid (UDCA) therapy is the most effective and approved treatment for PBC and leads to a favorable outcome in the vast majority of cases. Although the etiology of PBC has not yet been elucidated, human leukocyte antigen (HLA) class II alleles have been consistently associated with disease onset for decades. Individuals in different geographic regions of the world may have varying susceptibility alleles that reflect indigenous triggering antigens. In this review, we describe the influence of HLA alleles and other gene polymorphisms on PBC along with the results of genome-wide association studies (GWAS) on this disease.

The epigenetics of PBC: The link between genetic susceptibility and environment

Primary biliary cholangitis (PBC) previously known as primary biliary cirrhosis is an autoimmune disease-associated with progressive cholestasis, the presence of autoreactive T cell and characteristic serological autoantibodies. Genetic and genome-wide association studies (GWAS) have recently shed light on the genetic background of PBC. Besides that some causal nucleotide changes and mechanisms remain largely unknown as suggested for example, by the observation that monozygotic twins have an identical DNA sequence even if presents some phenotypic differences that may be consequences of different exposures to environmental stressors. For this reason, it is believed that epigenetic mechanisms may be involved in PBC pathogenesis, as already demonstrated in many autoimmune diseases and can eventually provide an understanding that has been missed from genetics alone. This review will focus on the most commonly studied epigenetic modifications already demonstrated in PBC; special attention will be paid also to other epigenetic mechanisms so far not demonstrated in PBC patients, but that could increase our understanding in PBC pathogenesis.

Recent advances in the diagnosis and treatment of primary biliary cholangitis

Primary biliary cholangitis (PBC), formerly referred to as primary biliary cirrhosis, is an infrequent progressive intrahepatic cholestatic autoimmune illness that can evolve into hepatic fibrosis, hepatic cirrhosis, hepatic failure, and, in some cases, hepatocellular carcinoma. The disease itself is characterized by T-lymphocyte-mediated chronic non-suppurative destructive cholangitis and elevated serum levels of extremely specific anti-mitochondrial autoantibodies (AMAs). In this article, we will not only review epidemiology, risk factors, natural history, predictive scores, radiologic approaches (e.g., acoustic radiation force impulse imaging, vibration controlled transient elastography, and magnetic resonance elastography), clinical features, serological characteristics covering biochemical markers, immunoglobulins, infections markers, biomarkers, predictive fibrosis marker, specific antibodies (including AMAs such as AMA-M2), anti-nuclear autoantibodies [such as anti-multiple nuclear dot autoantibodies (anti-sp100, PML, NDP52, anti-sp140), anti-rim-like/membranous anti-nuclear autoantibodies (anti-gp210, anti-p62), anti-centromere autoantibodies, and some of the novel autoantibodies], histopathological characteristics of PBC, diagnostic advances, and anti-diastole of PBC. Furthermore, this review emphasizes the recent advances in research of PBC in terms of therapies, including ursodeoxycholic acid, budesonide, methotrexate, obeticholic acid, cyclosporine A, fibrates such as bezafibrate and fenofibrate, rituximab, mesenchymal stem cells transplant, and hepatic transplant. Currently, hepatic transplant remains the only optimal choice with acknowledged treatment efficiency for end-stage PBC patients.

Prevalence of Systemic Sclerosis in Primary Biliary Cholangitis Using the New ACR/EULAR Classification Criteria

OBJECTIVE

Systemic sclerosis (SSc) is a well-established disease associated with primary biliary cholangitis (PBC). However, the original 1980 American College of Rheumatology (ACR) criteria have poor sensitivity, especially for the detection of earlier SSc in previous studies. The objective was to evaluate the prevalence of SSc in patients with PBC using more sensitive 2001 LeRoy and Medsger criteria and the 2013 ACR/European League Against Rheumatism (EULAR) classification criteria. The secondary objective was to evaluate the frequency of individual clinical features.

METHODS

One hundred consecutive patients with PBC without previously diagnosed SSc were recruited between 2005 and 2007 from a tertiary care gastroenterology clinic. All patients underwent a complete clinical examination, determination of SSc-specific antibodies, and a nailfold capillary microscopy. Fulfillment of the 3 different criteria sets was analyzed, along with individual disease features.

RESULTS

Of 100 patients with PBC, 1% met the ACR 1980 criteria, 22% met the 2001 LeRoy and Medsger criteria for early SSc, and 17% the 2013 ACR/EULAR criteria. Raynaud phenomenon, SSc-related antibodies, and SSc capillaroscopic patterns were the most prevalent findings, with the highest sensitivities to help guide future screening.

CONCLUSION

Our data show a high prevalence of SSc in patients with PBC with probable underestimation by previous studies using the original ACR criteria. Comorbid SSc should be actively searched for based on newly described criteria to improve detection and increase benefits of earlier treatment.

Obeticholic acid for the treatment of primary biliary cirrhosis

There is significant unmet need in Primary Biliary Cholangitis (PBC) in patients under-responsive to the only approved therapy Ursodeoxycholic Acid (UDCA) who are at increased risk of progressing to end-stage liver disease. Obeticholic Acid (OCA) is a farnesoid X receptor (FXR) agonist which has been evaluated as a second line therapy in PBC and has recently been licenced by the FDA. Areas covered: The pharmacology and biology of OCA as an FXR agonist and its clinical benefits. A systematic review was undertaken of published literature, meeting abstracts and trial registries using the search terms FXR, FGF-19 (& FGF-15), Obeticholic Acid and INT-747. Expert commentary: OCA reduces exposure to toxic hydrophobic bile acids through reduction in bile acid synthesis (by direct and indirect (via enterocyte-released FGF19) actions on Cyp7A1-mediated bile acid synthesis) and bile acid excretion by hepatocytes. It significantly improves liver biochemical parameters strongly associated with risk of disease progression in UDCA under-responsive patients and the key side-effect of pruritus can be reduced by optimised dosing. OCA will be the first stratified therapy introduced in PBC, however confirmatory trial and real life data are needed to confirm that suggestive biochemical improvements are matched by improvement in key clinical outcomes.

A Placebo-Controlled Trial of Obeticholic Acid in Primary Biliary Cholangitis

BACKGROUND

Primary biliary cholangitis (formerly called primary biliary cirrhosis) can progress to cirrhosis and death despite ursodiol therapy. Alkaline phosphatase and bilirubin levels correlate with the risk of liver transplantation or death. Obeticholic acid, a farnesoid X receptor agonist, has shown potential benefit in patients with this disease.

METHODS

In this 12-month, double-blind, placebo-controlled, phase 3 trial, we randomly assigned 217 patients who had an inadequate response to ursodiol or who found the side effects of ursodiol unacceptable to receive obeticholic acid at a dose of 10 mg (the 10-mg group), obeticholic acid at a dose of 5 mg with adjustment to 10 mg if applicable (the 5-10-mg group), or placebo. The primary end point was an alkaline phosphatase level of less than 1.67 times the upper limit of the normal range, with a reduction of at least 15% from baseline, and a normal total bilirubin level.

RESULTS

Of 216 patients who underwent randomization and received at least one dose of obeticholic acid or placebo, 93% received ursodiol as background therapy. The primary end point occurred in more patients in the 5-10-mg group (46%) and the 10-mg group (47%) than in the placebo group (10%; P<0.001 for both comparisons). Patients in the 5-10-mg group and those in the 10-mg group had greater decreases than those in the placebo group in the alkaline phosphatase level (least-squares mean, -113 and -130 U per liter, respectively, vs. -14 U per liter; P<0.001 for both comparisons) and total bilirubin level (-0.02 and -0.05 mg per deciliter [-0.3 and -0.9 μmol per liter], respectively, vs. 0.12 mg per deciliter [2.0 μmol per liter]; P<0.001 for both comparisons). Changes in noninvasive measures of liver fibrosis did not differ significantly between either treatment group and the placebo group at 12 months. Pruritus was more common with obeticholic acid than with placebo (56% of patients in the 5-10-mg group and 68% of those in the 10-mg group vs. 38% in the placebo group). The rate of serious adverse events was 16% in the 5-10-mg group, 11% in the 10-mg group, and 4% in the placebo group.

CONCLUSIONS

Obeticholic acid administered with ursodiol or as monotherapy for 12 months in patients with primary biliary cholangitis resulted in decreases from baseline in alkaline phosphatase and total bilirubin levels that differed significantly from the changes observed with placebo. There were more serious adverse events with obeticholic acid. (Funded by Intercept Pharmaceuticals; POISE ClinicalTrials.gov number, NCT01473524; Current Controlled Trials number, ISRCTN89514817.).

Fine-mapping analysis revealed complex pleiotropic effect and tissue-specific regulatory mechanism of TNFSF15 in primary biliary cholangitis, Crohn's disease and leprosy

Genetic polymorphism within the 9q32 locus is linked with increased risk of several diseases, including Crohn’s disease (CD), primary biliary cholangitis (PBC) and leprosy. The most likely disease-causing gene within 9q32 is TNFSF15, which encodes the pro-inflammatory cytokine TNF super-family member 15, but it was unknown whether these disparate diseases were associated with the same genetic variance in 9q32, and how variance within this locus might contribute to pathology. Using genetic data from published studies on CD, PBC and leprosy we revealed that bearing a T allele at rs6478108/rs6478109 (r² = 1) or rs4979462 was significantly associated with increased risk of CD and decreased risk of leprosy, while the T allele at rs4979462 was associated with significantly increased risk of PBC. In vitro analyses showed that the rs6478109 genotype significantly affected TNFSF15 expression in cells from whole blood of controls, while functional annotation using publicly-available data revealed the broad cell type/tissue-specific regulatory potential of variance at rs6478109 or rs4979462. In summary, we provide evidence that variance within TNFSF15 has the potential to affect cytokine expression across a range of tissues and thereby contribute to protection from infectious diseases such as leprosy, while increasing the risk of immune-mediated diseases including CD and PBC.

Toward precision medicine in primary biliary cholangitis

Primary biliary cholangitis is a chronic, cholestatic liver disease characterized by a heterogeneous presentation, symptomatology, disease progression and response to therapy. In contrast, clinical management and treatment of PBC is homogeneous with a 'one size fits all' approach. The evolving research landscape, with the emergence of the -omics field and the availability of large patient cohorts are creating a unique opportunity of translational epidemiology. Furthermore, several novel disease and symptom-modifying agents for PBC are currently in development. The time is therefore ripe for precision medicine in PBC. In this manuscript we describe the concept of precision medicine; review current approaches to risk-stratification in PBC, and speculate how precision medicine in PBC might develop in the near future.

The changing faces of cholangitis

A variety of diseases are included under the umbrella term ‘cholangitis’, including hepatobiliary diseases with an autoimmune pathogenesis (such as primary sclerosing cholangitis, primary biliary cholangitis, and IgG4-associated sclerosing cholangitis) and disease processes associated with intraductal stones and infectious etiologies (such as ascending bacterial cholangitis, recurrent pyogenic cholangitis, and liver fluke-associated cholangitis). Recent advances in the pathophysiologic bases of these disorders, particularly with respect to the autoimmune variety, are allowing improved diagnosis and prognostication as well as providing the opportunity to refine and re-imagine treatment modalities. The aim of this review is to highlight selected advances in cholangitis research that point to novel insights into the pathophysiology, diagnosis, and treatment of this diverse array of disorders.

Evolving Trends in Female to Male Incidence and Male Mortality of Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) has been regarded as female-predominant without evidence of gender difference in survival. We aimed to compare the overall survival, incidence and prevalence of PBC in two well defined population-based studies over a recent decade, considering also sex ratios and mortality. We have taken advantage of population-wide records, during 2000-2009, in Lombardia, Northern Italy, and Denmark. We focused on the incident cases of PBC, including gender and outcome, among 9.7 million inhabitants of Lombardia and 5.5 million of Denmark. In Lombardia there were 2,970 PBC cases with a female:male ratio of 2.3:1. The age/sex-adjusted annual incidence of PBC was 16.7 per million. Point prevalence was 160 per million on January 1(st) 2009. In Denmark there were 722 cases of incident PBC, female:male ratio was 4.2:1, and the annual incidence was 11.4 per million, a point prevalence of 115 per million in 2009. Cox regression multivariate analysis identified male sex as an independent predictor of all-cause mortality in both Italian (HR 2.36) and Danish population (HR 3.04). Our data indicate for PBC a sex ratio significantly lower than previously cited, a reversal of the usual latitudinal difference in prevalence and a surprisingly higher overall mortality for male patients.

A contemporary perspective on the molecular characteristics of mitochondrial autoantigens and diagnosis in primary biliary cholangitis

Primary biliary cholangitis (PBC) is an autoimmune hepatobiliary disease characterized by immune mediated destruction of the intrahepatic small bile ducts and the presence of antimitochondrial antibodies (AMAs). The mitochondrial autoantigens have been identified as the E2 subunits of the 2-oxo-acid dehydrogenase complex, including the E2 subunits of pyruvate dehydrogenase, branched-chain 2-oxo acid dehydrogenase complex, oxoglutarate dehydrogenase complex, E3 binding protein and PDC E1 alpha subunit. The AMA epitope is mapped within the E2 lipoic acid binding domain, which is particularly important for oxidative phosphorylation. In addition, lipoic acid, which serves as a swinging arm to capture electrons, is particularly susceptible to an electrophilic attack and may provide clues to the etiology of PBC. This review emphasizes the molecular characteristics of AMAs, including detection, immunochemistry and the putative role in disease. These data have significance not only specifically for PBC, but generically for autoimmunity.

It is time to change primary biliary cirrhosis (PBC): New nomenclature from "cirrhosis" to "cholangitis", and upcoming treatment based on unveiling pathology

Primary biliary cirrhosis (PBC) is a chronic, organ-specific, autoimmune liver disease characterized by progressive cholestasis, eventually leading to cirrhosis. Several lines of evidence have revealed a crucial role of adaptive as well as innate immune responses in the etiopathogenesis of PBC, and more recently, the biology of bile duct cells and genome-wide association studies (GWAS) demonstrated several key molecules and pathways in this enigmatic disease. Although ursodeoxycholic acid (UDCA) has been the only approved drug for PBC with clinical evidences for improvement of long-term outcomes, a substantial population have suboptimal responses to UDCA, resulting in unfavorable outcomes. In this regard, second-line treatment for patients refractory to UDCA is strongly awaited. In Japan, bezafibrate (BF) has been frequently used for this purpose, yet recent clinical trials failed to clearly demonstrate clinical efficacy of BF. Novel pharmacotherapies targeted to key molecules and pathways in PBC are upcoming. Finally, we sincerely call on all members of the Japan Society of Hepatology to use from this moment on the name "primary biliary cholangitis" for the disease known by its abbreviation PBC, in keeping with a very recent global agreement.