Demographic, lifestyle, medical and familial factors associated with primary biliary cirrhosis

Primary biliary cholangitis: pathogenesis and therapeutic opportunities

Primary biliary cholangitis is a chronic, seropositive and female-predominant inflammatory and cholestatic liver disease, which has a variable rate of progression towards biliary cirrhosis. Substantial progress has been made in patient risk stratification with the goal of personalized care, including early adoption of next-generation therapy with licensed use of obeticholic acid or off-label fibrate derivatives for those with insufficient benefit from ursodeoxycholic acid, the current first-line drug. The disease biology spans genetic risk, epigenetic changes, dysregulated mucosal immunity and altered biliary epithelial cell function, all of which interact and arise in the context of ill-defined environmental triggers. A current focus of research on nuclear receptor pathway modulation that specifically and potently improves biliary excretion, reduces inflammation and attenuates fibrosis is redefining therapy. Patients are benefiting from pharmacological agonists of farnesoid X receptor and peroxisome proliferator-activated receptors. Immunotherapy remains a challenge, with a lack of target definition, pleiotropic immune pathways and an interplay between hepatic immune responses and cholestasis, wherein bile acid-induced inflammation and fibrosis are dominant clinically. The management of patient symptoms, particularly pruritus, is a notable goal reflected in the development of rational therapy with apical sodium-dependent bile acid transporter inhibitors.

Sex differences in clinical presentation and prognosis in patients with primary biliary cholangitis

Objectives: Primary biliary cholangitis (PBC) is a chronic inflammatory disease of the small intrahepatic bile ducts disproportionally affecting women. Timely diagnosis and treatment can often prevent progression to liver cirrhosis. We hypothesized PBC diagnosis in male patients is delayed and prognosis impaired. We, therefore, conducted a case-control study and compared clinical and prognostic features among male and female patients with PBC.Materials and methods: 49 male patients with PBC treated at a German tertiary care center between 2006 and 2017 were identified and compared to 98 age-matched female controls. Prospectively collected clinical/biochemical data were analyzed retrospectively. Liver biopsies were scored in a blinded fashion. Prognostic parameters were calculated using established prognostic scores (GLOBE, PBC-UKE). Statistical analysis was performed using Mann-Whitney test and Fisher´s exact test.Results: At PBC diagnosis, male patients reported significantly less PBC-associated symptoms as compared to female controls (34 versus 71%, p < .01). Compared to female patients, median time from onset of PBC-related symptoms and/or first reported elevated cholestatic biochemical parameters to PBC diagnosis was significantly increased in men (36 versus 12 months, p = .02). In addition, male patients underwent liver biopsy to establish PBC diagnosis more frequently, tended to show more advanced fibrosis and showed significantly poorer prognostic PBC score results. Hepatocellular carcinoma was only observed in male patients (n = 3).Conclusions: When compared to women, men with PBC suffer from less PBC-related symptoms, receive PBC diagnosis delayed and have a worse prognosis. Despite its rarity, the diagnosis of PBC should be considered in men with elevated cholestatic parameters.

Epigenetic Modifications in Generalized Autoimmune Epithelitis: Sjögren's Syndrome and Primary Biliary Cholangitis

Sjögren's syndrome (SjS) and primary biliary cholangitis (PBC) can be classified as a model of generalized autoimmune epithelitis based on their frequent coexistence in clinical practice and the highly specific immune mediated injury of target epithelial cells. Both of these autoimmune diseases are characterized by female predominance, highly specific circulating autoantibodies, and immune-mediated destruction of the salivary and lachrymal glands and the biliary epithelial cells, respectively. Although the genetic predisposition has been well described for both diseases, genetic studies have failed to completely elucidate their pathogenesis. The recent integration of epigenetic data, analyzing the different cellular partners, opens new perspectives and allows for better understanding of these complex and still incurable diseases. Epigenetic studies on SjS have elucidated the role of DNA methylation alterations in disease pathogenesis, while epigenetic changes that influence expression of genes on the X chromosome have been implicated in the geo-variability and occurrence of PBC. The aim of this review is to describe the advances in epigenetics in the field of autoimmune epithelitis as well as to highlight how epigenetic changes could contribute to better understanding of disease pathogenesis and progression. These advances could yield insights on novel therapeutic interventions.

Increase trend in the prevalence and male-to-female ratio of primary biliary cholangitis, autoimmune hepatitis, and primary sclerosing cholangitis in Japan

AIM

Autoimmune liver diseases (AILD) including autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC) impose a significant burden on public health, and it is important to estimate their prevalence. We carried out a nationwide, hospital-based, epidemiological survey of AIH, PBC, and PSC, and compared the results with those from previous surveys.

METHOD

We randomly selected health-care facilities used in the survey from a list of all facilities in Japan. The selection rate was determined according to a stratification based on the facility characteristics and scale. We sent questionnaires to the selected facilities enquiring about the number and sex of patients with AILD who visited the facility in 2016. An identical survey was undertaken for AIH/PBC in 2004 and for PSC in 2007; we carried out a comparative analysis of these data.

RESULTS

We selected 1793 departments from health centers all over Japan. Of them, 1078 (60.1%) responded to the questionnaires. The number of reported patients with AIH, PBC, and PSC was 8505, 10 847, and 906, respectively, and point prevalence was 23.9 (95% confidence interval, 23.3-24.5) for AIH (8.7 in 2004), 33.8 (33.0-34.6) for PBC (11.6 in 2004), and 1.80 (1.75-1.85) for PSC (0.95 in 2007) per 100 000 population. Male-to-female patient ratio of AILD was 1:4.3 for AIH (1:6.9 in 2004), 1:3.9 for PBC (1:7.1 in 2004), and 1:0.88 for PSC (1:1.4 in 2007).

CONCLUSION

The current study indicates an increasing trend of prevalence as well as male-to-female patient ratio of AILD in Japan.

Variant and Specific Forms of Autoimmune Cholestatic Liver Diseases

Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are the main autoimmune cholestatic liver diseases. IgG4-associated sclerosing cholangitis is another distinct immune-mediated cholestatic disorder of unknown aetiology that is frequently associated with autoimmune pancreatitis or other IgG4-related diseases. Although the majority of PBC and PSC patients have a typical presentation, there are common and uncommon important variants or specific subgroups that observed in everyday routine clinical practice. In this updated review, we summarize the published data giving also our own experience on the variants and specific groups of autoimmune cholestatic liver diseases. Actually, we give in detail the underlining difficulties and the rising dilemmas concerning the diagnosis and management of these special conditions in the clinical spectrum of autoimmune cholestatic liver diseases including the IgG4-associated sclerosing cholangitis highlighting also the uncertainties and the potential new eras of the research agenda.

Concomitant Sjögren's Syndrome Was Not Associated with a Poorer Response or Outcomes in Ursodeoxycholic Acid-Treated Patients with Primary Biliary Cholangitis

AIM

Patients with primary biliary cholangitis (PBC) have at least 60% probability of having an autoimmune extrahepatic condition, with the most common being Sjögren's syndrome (SS). The impacts of SS on the response and outcomes in ursodeoxycholic acid (UDCA)-treated patients with PBC, however, remain unclear. The aim of this study was to document the biochemical responses and clinical outcomes of UDCA-treated patients with concomitant SS and to compare the findings to those of patients with PBC alone.

METHODS

Data from consecutive patients with PBC who visited West China Hospital affiliated with Sichuan University between October 2013 and October 2017 were reviewed retrospectively.

RESULTS

The study populations consisted of 226 patients with PBC alone and 56 with PBC/SS. The median ages, proportions of female patients, Fib-4 scores, and aspartate aminotransferase (AST)/platelet ratio index (APRI) at baseline in the two cohorts were similar. At presentation, patients with PBC/SS had higher serum IgG levels and positive rates for serum antinuclear antibody (ANA) than patients with PBC alone (all P < 0.05). There was no statistically significant difference between the rate of biochemical response to UDCA at 1 year in the PBC/SS and PBC alone groups. The UK-PBC risk scores and GLOBE scores in UDCA-treated patients in the two cohorts were also similar. During the follow-up period, the differences in the liver enzyme levels, Fib-4 scores, APRI, and incidence of liver-related adverse events were not significant.

CONCLUSIONS

The results of this retrospective, single-center study suggest that the response and clinical outcomes of UDCA-treated patients with PBC are not adversely affected by concomitant SS.

Systemic sclerosis and primary biliary cholangitis: An overlapping entity?

Systemic sclerosis (SSc) is a complex autoimmune disease that may lead to skin and internal organ fibrosis. Based on skin involvement, two subsets of the disease are recognized (limited cutaneous SSc and diffuse cutaneous SSc). The new 2013 American College of Rheumatology/European League against Rheumatism classification criteria allow to identify SSc patients at the early stage of the disease that allows new research avenues. The aetiology of the disease is still unknown, but it has an important autoimmune basis and its association with other autoimmune diseases has been reproducibly reported. Among them, primary biliary cholangitis is considered the most common liver disease in SSc. The aim of this review is to provide an overview on recent findings about SSc associated to primary biliary cholangitis. Although the aetiology of the two diseases is still unknown, data suggest that these two disorders share the expression of fibrogenic cytokines, involved both in generation and function of T lymphocytes subpopulation (Th17 cells) and regulatory T lymphocytes. In addition, the relationships between SSc and primary biliary cholangitis may be closer as suggested by the presence of primary biliary cholangitis-specific antibodies in SSc patients and vice versa. Recent findings confirm a prevalence of overt primary biliary cholangitis in about 2% of SSc population, in particular in patients with limited cutaneous SSc and positive anticentromere antibodies. The prevalence increases if also patients with only primary biliary cholangitis-specific antibodies are considered. Data regarding SSc prevalence in primary biliary cholangitis patients have also been recently clarified. Altogether, stimulating results are moving the field forward regarding the relationships of these two autoimmune and fibrotic disorders that may belong to an overlapping entity.

Pathogen infections and primary biliary cholangitis

Primary biliary cholangitis (PBC) is a multi-factorial disease caused by the interaction of both genetic predisposition and environmental triggers. Bacterial infection has been investigated most intensively, both epidemiologically and experimentally, as a prime environmental aetiology in PBC. The association of recurrent history of urinary tract infection (UTI) with PBC has been frequently confirmed by several large-scale, case-control studies, despite variation in geographic area or case-finding methods. Escherichia coli is a predominant pathogen in most cases with UTI. Animal studies and molecular mimicry analysis between the human and E. coli E2 subunit of the 2-oxo-acid dehydrogenase complexes demonstrated that E. coli infection is a key factor in breaking immunological tolerance against the mitochondria, resulting in the production of anti-mitochondrial autoantibodies (AMA), the disease-specific autoantibodies of PBC. Novosphingobium aromaticivorans, a ubiquitous xenobiotic-metabolizing bacterium, is another candidate which may be involved in the aetiology of PBC. Meanwhile, improved environmental hygiene and increased prevalence of PBC, especially in males, may argue against the aetiological role of bacterial infection in PBC. Multiple mechanisms can result in the loss of tolerance to mitochondrial autoantigens in PBC; nonetheless, bacterial infection is probably one of the dominant pathways, especially in female patients. Notably, there is a rising prevalence of male patients with PBC. With increasing exposure to environmental xenobiotics in both genders, studies directed towards identifying the environmental culprit with systematically designed case-control studies are much needed to further determine the environmental factors and role of bacterial infections in PBC.

Diagnosis and Management of Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is a chronic, cholestatic, autoimmune disease with a variable progressive course. PBC can cause debilitating symptoms including fatigue and pruritus and, if left untreated, is associated with a high risk of cirrhosis and related complications, liver failure, and death. Recent changes to the PBC landscape include a name change, updated guidelines for diagnosis and treatment as well as new treatment options that have recently become available. Practicing clinicians face many unanswered questions when managing PBC. To assist these healthcare providers in managing patients with PBC, the American College of Gastroenterology (ACG) Institute for Clinical Research & Education, in collaboration with the Chronic Liver Disease Foundation (CLDF), organized a panel of experts to evaluate and summarize the most current and relevant peer-reviewed literature regarding PBC. This, combined with the extensive experience and clinical expertise of this expert panel, led to the formation of this clinical guidance on the diagnosis and management of PBC.

Extrahepatic autoimmunity in autoimmune liver disease

The most important autoimmune liver disease include: autoimmune hepatitis, primary biliary cholangitis and primary sclerosing cholangitis. In general, about one in three patients with an autoimmune liver disease have a concomitant extrahepatic autoimmune disease, which may include rheumatological, endocrinological, gastrointestinal, pulmonary or dermatological conditions. The pathogenesis of these conditions includes the production of both innate and adaptive immune responses targeting cholangiocytes as well as different extrahepatic tissues. In this sense, extrahepatic autoimmunity represent a continuous spectrum of autoimmunity involving liver and extrahepatic tissues. This review aims to focus the clinical and pathophysiological aspects of extrahepatic autoimmunity associated to autoimmune liver diseases.

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.

Association of smoking with liver fibrosis and mortality in primary biliary cholangitis

BACKGROUND

The outcome of primary biliary cholangitis (PBC) is affected by both genetic and environmental factors.

OBJECTIVE

The aim of this study was to study the effect of smoking on liver histology and mortality in a genetically homogeneous population having PBC.

PATIENTS AND METHODS

Smoking and drinking habits at diagnosis (based on standard criteria) were recorded in 171 Cretan patients with PBC (163 women). A total of 148 patients had a liver biopsy. Odds ratios were calculated with logistic regression analysis. Kaplan-Meier curves were used for mortality estimation.

RESULTS

Smoking was associated with alcohol consumption of more than 20 g/day [adjusted odds ratio (AOR)=2.20, 95% CI: 1.029-4.099], severe steatosis (AOR=5.31, 95% CI: 2.019-9.919), and fibrosis stage F3-F4 (AOR=1.21, 95% CI: 1.015-3.031). Heavy smoking, years of passive smoking, and serious necroinflammatiοn were independent factors associated with advanced fibrosis after adjustment for sex, age, BMI, and alcohol consumption in multivariate analysis. For every pack-year increase in smoking intensity, there was a 3.2 times higher likelihood of advanced fibrosis (95% CI: 2.018-6.294). Increased mortality was found in smokers with advanced PBC.

CONCLUSION

There is an association between smoking, whether active or passive, and advanced fibrosis in PBC. Mortality is increased in smokers with advanced disease at presentation.

Development and validation of a novel score for fibrosis staging in patients with chronic hepatitis B

BACKGROUND & AIMS

Non-invasive assessment methods for liver fibrosis are urgently needed. The present study aimed to develop a novel diagnostic model for fibrosis staging in patients with chronic hepatitis B.

METHODS

A cross-sectional set of 417 chronic hepatitis B patients who underwent liver biopsy was enrolled and the METAVIR score was adopted as the reference of fibrosis staging.

RESULTS

Among thyroid hormones, only the level of free tetraiodothyronine (FT4) decreased gradually with the METAVIR fibrosis score (P < .001). FibroStage, a novel diagnosis model that incorporates data on FT4, platelets, cholinesterase, gamma-glutamyl transpeptidase, and age, was developed using the deriving set (n = 219). For the diagnosis of significant fibrosis, the FibroStage model had a significantly higher area under the receiver operating curve than did the FibroIndex, Forn, and Lok models (all of P < .01) and tended to better than the fibrosis-4 (P = .0791) but comparable with the aspartate transaminase-to-platelet ratio index model (P = .1694). For the diagnosis of advanced fibrosis, FibroStage had a higher area under the receiver operating curve than did the aspartate transaminase-to-platelet ratio index, FibroIndex, Forn, and Lok models (all of P < .05) and had a comparable area under the receiver operating curve with the fibrosis-4 model (P = .2109). For the diagnosis of cirrhosis, the area under the receiver operating curve of FibroStage was higher than those of the aspartate transaminase-to-platelet ratio index, fibrosis-4, FibroIndex, and Lok (all of P < .05) models and was comparable with Forn (P = .1649). These results was validated by a validation set (n = 198).

CONCLUSION

FT4 may be an indicator for fibrosis staging in chronic hepatitis B patients. FibroStage is a better model than aspartate transaminase-to-platelet ratio index, fibrosis-4, FibroIndex, Forn, and Lok for the comprehensively diagnosis of significant and advanced fibrosis and cirrhosis.

A Young Man with Non-alcoholic Steatohepatitis and Serum Anti-mitochondrial Antibody Positivity

A 37-year-old obese man who was a social drinker was admitted to our hospital to undergo a detailed examination for liver injury with anti-mitochondrial antibody positivity. Abdominal ultrasonography revealed moderate fatty liver. A histological analysis showed steatosis of approximately 30% of the hepatocytes, focal necrosis, a few ballooning hepatocytes and lobular inflammation suggestive of steatohepatitis, epithelioid granuloma and irregularity of the sequence of the bile duct epithelium accompanied by lymphocyte infiltration suggestive of chronic cholangitis. He was diagnosed with non-alcoholic steatohepatitis complicated with primary biliary cholangitis. His liver injury was improved by weight loss and high-dose ursodeoxycholic acid treatment.

Characteristics and Outcomes of Liver Transplantation for Primary Biliary Cholangitis in Young Patients: Analysis of the United Network for Organ Sharing Database

BACKGROUND

Primary biliary cholangitis (PBC) in younger patients has been suggested to require liver transplantation (LT) in early adulthood, but data is limited on its outcomes. We aimed to evaluate the characteristics and outcome of LT in young patients with PBC in comparison with older adults.

METHODS

The United Network for Organ Sharing database was analyzed for all patients with PBC who underwent LT between 2000 and 2012. Based on age at the time of LT, subjects were divided into 2 groups: young patients (≤40 y) and older adults (≥41 y). Baseline demographics, clinical parameters, and outcomes of LT were then compared between the 2 groups. Univariable and multivariable analyses were performed to assess the factors associated with outcomes of LT.

RESULTS

A total of 2084 patients with PBC were included in the analysis with 158 young patients. Compared with older adults, younger patients were more likely to be male (27.2% versus 15.4%) and nonwhite (43.7% versus 21.5%), but they were less likely to have obesity, diabetes, or hypertension (P < 0.05) and had a lower mortality (8.2% versus 15.1%) but higher retransplantation rate (14.6% versus 4.7%) (P < 0.001). On multivariable analysis, older age, dialysis or ventilator use, and lower albumin were associated with high post-LT mortality.

CONCLUSIONS

Compared with older adults, early-onset PBC in younger patients requiring LT had higher percentage of males and nonwhites and had a lower prevalence of metabolic comorbidities but higher retransplantation rates. Further studies are warranted to confirm these findings.

Primary biliary cholangitis in Spain. Results of a Delphi study of epidemiology, diagnosis, follow-up and treatment

INTRODUCTION

primary biliary cholangitis (PBC) is a rare disease with limited data regarding its epidemiology and standard clinical management in Spain.

OBJECTIVE

to gain insight into the epidemiology, patient flow, diagnosis, follow-up and treatment of PBC in Spain.

METHODS

a review of the literature and Delphi study involving 28 specialists in two rounds of consultations and an in-person results validation workshop.

RESULTS

there are approximately 9,400 patients with PBC in Spain, with an annual incidence of 0.51-3.86 cases/100,000 population. Albeit, a high error margin may be presumed due to the scarcity of relevant studies on this subject. Several months may elapse from suspicion to a confirmed diagnosis, usually by a gastroenterologist or hepatologist. The role of the liver biopsy for diagnosis and follow-up is heterogeneous. Overall, 95% of patients are treated with ursodeoxycholic acid (UDCA) and response is primarily monitored using the Barcelona criteria. Follow-up is performed every six months, with a heterogeneous use of the various available techniques. No recommendations or second-line commercial drugs are available in the case of no response, inadequate response or intolerance to UDCA.

CONCLUSIONS

while epidemiology may be estimated based on expert opinions, national registries are needed to provide accurate, up-to-date information on epidemiological parameters, disease stage and response to treatment in patients with PBC. Furthermore, novel therapies are required for selected patient groups.

Epidemiology and liver transplantation burden of primary biliary cholangitis: a retrospective cohort study

BACKGROUND

There is a wealth of data documenting the epidemiology of primary biliary cholangitis (PBC) globally; however, the epidemiology of PBC has not been as well studied in Canada. Our study characterized the Canadian prevalence of PBC and the number of liver transplantations because of PBC.

METHODS

For this retrospective cohort study we used national hospital administrative records from the Canadian Institute for Health Information, with the exception of Quebec for the prevalence estimate and Quebec and British Columbia for the transplant analysis. Prevalent patients were identified through a diagnostic code for PBC of the Canadian version of the 10th revision of the International Classification of Diseases. PBC transplant patients were identified from their transplant record. Descriptive statistics were used to summarize the characteristics of the study cohorts.

RESULTS

In 2015, 8680 patients with PBC were identified in Canada, translating to a prevalence of 318 cases per million. Annual prevalence by province varied, ranging from 283 (95% confidence interval [CI] 269-297) cases per million to 465 (95% CI 426-504) cases per million, and the 6-year PBC liver transplantation rate ranged from 3.17 (95% CI 1.27-6.54) to 5.92 (95% CI 3.71-9.08) per million. The Atlantic provinces exhibited the highest PBC prevalence and close to the highest 6-year liver transplantation rate (465 [95% CI 426-504] cases per million and 5.70 [95% CI 426-504, 3.19-9.56] cases per million, respectively). We observed the lowest PBC prevalence (283 [95% CI 269-297] cases per million) and the second lowest 6-year liver transplantation rate in Ontario (3.37 [95% CI 2.47-4.50] cases per million).

INTERPRETATION

The prevalence of PBC that we found in Canada is similar to the prevalence reported in other studies, but our work also indicates geographic variation within this country. Given our finding of geographic clustering of PBC across Canada, we hypothesize that environmental and genetic factors contribute to the pathogenesis of this condition.

Comprehensive Review of Molecular Mechanisms during Cholestatic Liver Injury and Cholangiocarcinoma

Cholestatic liver injury is characterized by damage induced on the biliary tree and cholangiocytes, the cells lining the biliary tree, thus they are termed "cholangiopathies". Cholangiopathies include diseases such as Primary Biliary Cholangitis, Primary Sclerosing Cholangitis, Biliary Atresia and Cholangiocarcinoma. These pathologies lack viable therapies and most patients are diagnosed during late stage disease progression (with the exception of Biliary Atresia, which is found shortly after birth). The lack of therapies for these diseases has put a significant burden on the need for liver transplantation as this is the only indicative "cure" for cholangiopathies. The molecular mechanisms for cholangiopathies have been extensively studied; however, and unfortunately, the lack of effective biomarkers and therapeutics remains. In this review article we highlight the latest studies to investigate the molecular mechanisms regulating cholangiopathies and the potential therapeutics that might be discovered.

The British Society of Gastroenterology/UK-PBC primary biliary cholangitis treatment and management guidelines

Primary biliary cholangitis (formerly known as primary biliary cirrhosis, PBC) is an autoimmune liver disease in which a cycle of immune mediated biliary epithelial cell injury, cholestasis and progressive fibrosis can culminate over time in an end-stage biliary cirrhosis. Both genetic and environmental influences are presumed relevant to disease initiation. PBC is most prevalent in women and those over the age of 50, but a spectrum of disease is recognised in adult patients globally; male sex, younger age at onset (<45) and advanced disease at presentation are baseline predictors of poorer outcome. As the disease is increasingly diagnosed through the combination of cholestatic serum liver tests and the presence of antimitochondrial antibodies, most presenting patients are not cirrhotic and the term cholangitis is more accurate. Disease course is frequently accompanied by symptoms that can be burdensome for patients, and management of patients with PBC must address, in a life-long manner, both disease progression and symptom burden. Licensed therapies include ursodeoxycholic acid (UDCA) and obeticholic acid (OCA), alongside experimental new and re-purposed agents. Disease management focuses on initiation of UDCA for all patients and risk stratification based on baseline and on-treatment factors, including in particular the response to treatment. Those intolerant of treatment with UDCA or those with high-risk disease as evidenced by UDCA treatment failure (frequently reflected in trial and clinical practice as an alkaline phosphatase >1.67 × upper limit of normal and/or elevated bilirubin) should be considered for second-line therapy, of which OCA is the only currently licensed National Institute for Health and Care Excellence recommended agent. Follow-up of patients is life-long and must address treatment of the disease and management of associated symptoms.

The Genetics and Epigenetics of Primary Biliary Cholangitis

Both genetic background and environmental factors contribute to primary biliary cholangitis (PBC). Recent innovative technologies, such as genome-wide association studies, identified a remarkable number of susceptible nonhuman leukocyte antigen genes contributing to the development of PBC; however, they are primarily indicators of active immunologic responses commonly involved in autoimmune reactions. Thus, recent studies have focused on epigenetic mechanisms that would link genetic predisposition and environmental triggering factors. In PBC, methylation profiling and altered X chromosome architecture have been intensively explored in conjunction with a striking female predominance. Further, microRNAs have been found to be associated with the etiology of PBC.

Changes in the Epidemiology of Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is considered a model autoimmune disease, characterized by circulating anti-mitochondrial antibodies and a selective autoimmune destruction of intrahepatic cholangiocytes. PBC is heterogeneous in its presentation, symptomatology, disease progression, and response to therapy. The pathogenesis is still largely unknown and epidemiologic studies have facilitated the identification of risk factors and the understanding of disease prevalence, geographic variations, heterogeneity, and differences in sex ratio. Recent studies from large international cohorts have better identified prognostic factors suggesting a change in patient management based on risk-stratification tools to identify subgroups at greatest potential benefit from second-line therapies.

Using the Icelandic genealogical database to define the familial risk of primary biliary cholangitis

Hereditary factors in primary biliary cholangitis (PBC) have been well defined in genome-wide association studies, but there are few direct data available that define the relative risk (RR) for family members with an affected proband. An increased risk in first-degree relatives has been demonstrated in a variety of studies, but data have been lacking on further detailed associations for subsequent generations. The objective of this study was to use the unique Icelandic genealogical database to study the familiality of PBC. All patients with positive antimitochondrial antibody measurements in Iceland during the period 1991-2015 who fulfilled diagnostic criteria for PBC were included. The Icelandic genealogical database was used to assess familial relations. For each case of PBC, 10,000 control subjects matched for age, sex, and number of known relatives were randomly chosen from this database to calculate the familial RR of PBC. The average kinship coefficient (KC) of the patients was calculated and compared with the average KC of controls. Overall, 222 PBC patients were identified (182 females, 40 males; median age, 62 years). First-, second- and third-degree relatives of the PBC patients had a high RR of the disease: 9.13 (P < 0.0001), 3.61 (P = 0.014) and 2.59 (P = 0.008), respectively. In fourth- and fifth-degree relatives, the RR was also increased to 1.66 (P = 0.08) and 1.42 (P = 0.08), respectively. The average KC of the patients was also higher than that of the control subjects, with 21.34 × 10^-5 versus 9.56 × 10^-5 (P < 0.0001).

CONCLUSION

Relatives of PBC patients had markedly higher risk for development of the disease compared with controls and importantly our data demonstrate that the risk was significantly increased even in second- and third-degree relatives. (Hepatology 2018;68:166-171).

Evolution of our understanding of PBC

The discovery of mitochondrial autoantigens recognized by antimitochondrial antibodies (AMAs) in 1987 marked the dawn of a new era in primary biliary cholangitis (PBC) research. Since then, there has been substantial progress in our understanding of PBC partly bestowed by the development of innovative technologies in molecular biology, immunology, and genetics. Here, we review this evolutionary progress in understanding PBC. We now recognize that the epitopes of AMAs, CD4⁺, and CD8⁺ T cells are all mapped to the same region of the inner lipoyl domain of pyruvate dehydrogenase complex E2 subunit (PDC-E2), and that intrahepatic biliary epithelial cells (BECs) are exclusively targeted in PBC. BECs express PDC-E2 on apotopes in an immunologically intact form during apoptosis, but not other epithelial cells, which could explain the tissue specificity of PBC. In addition, genetic factors, environmental triggers, and epigenetic modifications play crucial roles in the development of PBC. Intact lipoylated PDC-E2, presumably after modification with xenobiotics such as 2-octynamide or 2-nonyamide that are abundantly present in the environment, is endocytosed by antigen-presenting cells and are presented to CD4⁺ or CD8⁺ T cells. An immune complex consisting of PDC-E2 and anti-PDC-E2 autoantibodies cross-present autoantigens in a more efficient manner. Finally, an adenylate uridine-rich element (ARE) Del -/- mouse model has been established, which presents a disease modeling human PBC, including female dominance as one of its most important features, and can be used to dissect the immunopathology of PBC. Expanding our knowledge of the pathology from a very early stage of the disease will provide the key to cure PBC.

The Importance of Sex Stratification in Autoimmune Disease Biomarker Research: A Systematic Review

The immune system is highly dynamic and regulated by many baseline characteristic factors. As such, significant variability may exist among different patient groups suffering from the same autoimmune disease (AD). However, contemporary research practices tend to take the reductionist aggregate approach: they do not segment AD patients before embarking on biomarker discovery. This approach has been productive: many novel AD biomarkers have recently been discovered. Yet, subsequent validation studies of these biomarkers tend to suffer from a lack of specificity, sensitivity, and reproducibility which hamper their translation for clinical use. To enhance reproducibility in validation studies, an optimal discovery-phase study design is paramount: one which takes into account different parameters affecting the immune system biology. In this systematic review, we highlight need for stratification in one such parameter, i.e., sex stratification. We will first explore sex differences in immune system biology and AD prevalence, followed by reported sex-bias in the clinical phenotypes of two ADs—one which more commonly affects females: systemic lupus erythematosus, and one which more commonly affects males: ankylosing spondylitis. The practice of sex stratification in biomarker research may not only advance the discovery of sex-specific AD biomarkers but more importantly, promote reproducibility in subsequent validation studies, thus easing the translation of these novel biomarkers from bench to bedside to improve AD diagnosis. In addition, such practice will also promote deeper understanding for differential AD pathophysiology in males and females, which will be useful for the development of more effective interventions for each sex type.

Pathophysiology of primary biliary cholangitis

Primary biliary cholangitis is a prototypical autoimmune disease characterized by an overwhelming female predominance, a distinct clinical phenotype, and disease specific anti-mitochondrial antibodies targeted against a well-defined auto-antigen. In a genetically susceptible host, multi-lineage loss of tolerance to the E2 component of the 2-oxo-dehydrogenase pathway and dysregulated immune pathways directed at biliary epithelial cells leads to cholestasis, progressive biliary fibrosis, and cirrhosis in a subset of patients. Several key insights have shed light on the complex pathogenesis of disease. First, characteristic anti-mitochondrial antibodies (AMAs) target lipoic acid containing immunodominant epitopes, particularly pyruvate dehydrogenase complex (PDC-E2), on the inner mitochondrial membrane of BECs. Next, breakdown of the protective apical bicarbonate rich umbrella may sensitize BECs to aberrant apoptotic pathways leaving the antigenic PDC-E2 epitope immunologically tact within an apoptotic bleb. A multi-lineage immune response ensues characterized by an imbalance between effector and regulatory activity resulting in progressive and self-perpetuating biliary injury. Genome wide studies shed light on important pathways involved in disease, key among them being IL-12. Epigenetic mechanisms and microRNAs may play help shed light on the missing heritability and female preponderance of disease. Taken together, these findings have dramatically advanced our understanding of disease and may lead to important therapeutic advances.

PBC and related extrahepatic diseases

Patients with PBC have at least 60% of probability to have an autoimmune extrahepatic condition. The pathogenesis of these conditions includes a common mechanism involving both innate and adaptive immune responses targeting cholangiocytes and different extrahepatic tissues. The recent EASL guidelines recommend the management of these conditions, although detailed practical treatments have not been indicated. Autoimmune extrahepatic conditions may include: rheumatologic, endocrine, pulmonary, gastrointestinal, dermatologic diseases. This review aims to focus the most important extrahepatic autoimmune conditions associated to PBC with practical recommendation regarding diagnostic approach and management.

NI-0801, an anti-chemokine (C-X-C motif) ligand 10 antibody, in patients with primary biliary cholangitis and an incomplete response to ursodeoxycholic acid

NI-0801 is a fully human monoclonal antibody against chemokine (C-X-C motif) ligand 10 (CXCL10), which is involved in the recruitment of inflammatory T cells into the liver. The safety and efficacy of NI-0801 was assessed in patients with primary biliary cholangitis. In this open-label phase 2a study, patients with primary biliary cholangitis with an inadequate response to ursodeoxycholic acid received six consecutive intravenous administrations of NI-0801 (10 mg/kg) every 2 weeks. Patients were followed up for 3 months after the last infusion. Liver function tests, safety assessments, as well as pharmacokinetic and pharmacodynamic parameters were evaluated at different time points throughout the dosing period and the safety follow-up period. Twenty-nine patients were enrolled in the study and were treated with NI-0801. The most frequently reported adverse events included headaches (52%), pruritus (34%), fatigue (24%), and diarrhea (21%). No study drug-related serious adverse events were reported. NI-0801 administration did not lead to a significant reduction in any of the liver function tests assessed at the end of the treatment period (i.e., 2 weeks after final NI-0801 administration) compared to baseline. Conclusion: Despite clear pharmacologic responses in the blood, no therapeutic benefit of multiple administrations of NI-0801 could be demonstrated. The high production rate of CXCL10 makes it difficult to achieve drug levels that lead to sustained neutralization of the chemokine, thus limiting its targetability. (Hepatology Communications 2018;2:492-503).

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.

An Update on the Treatment and Follow-up of Patients with Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by chronic granulomatous lymphocytic cholangitis of the small bile ducts. PBC was a leading indication for liver transplant in the United States; with early diagnosis and treatment, the majority of patients with PBC have a normal life expectancy. Pathogenesis involves inflammatory damage of bile duct epithelium secondary to innate and adaptive immune responses, and toxicity from accumulated bile acids. Cholestasis and disease progression can lead to cirrhosis. Extrahepatic complications include dyslipidemia, metabolic bone disease, and fat-soluble vitamin deficiency. Ursodeoxycholic acid is a well-established therapy. Novel targeted therapeutics are being developed.

Review article: next-generation transformative advances in the pathogenesis and management of autoimmune hepatitis

BACKGROUND

Advances in autoimmune hepatitis that transform current concepts of pathogenesis and management can be anticipated as products of ongoing investigations driven by unmet clinical needs and an evolving biotechnology.

AIM

To describe the advances that are likely to become transformative in autoimmune hepatitis, based on the direction of current investigations.

METHODS

Pertinent abstracts were identified in PubMed by multiple search terms. Full-length articles were selected for review, and a secondary bibliography was developed. The discovery process was repeated, and a tertiary bibliography was identified. The number of abstracts reviewed was 2830, and the number of full-length articles reviewed exceeded 150.

RESULTS

Risk-laden allelic variants outside the major histocompatibility complex (rs3184504, r36000782) are being identified by genome-wide association studies, and their gene products are potential therapeutic targets. Epigenetic changes associated with environmental cues can enhance the transcriptional activity of genes, and chromatin re-structuring and antagonists of noncoding molecules of ribonucleic acid are feasible interventions. The intestinal microbiome is a discovery field for microbial products and activated immune cells that may translocate to the periphery and respond to manipulation. Epidemiological studies and controlled interview-based surveys may implicate environmental and xenobiotic factors that warrant evidence-based changes in lifestyle, and site-directed molecular and cellular interventions promise to change the paradigm of treatment from one of blanket immunosuppression.

CONCLUSIONS

Advances in genetics, epigenetics, pathophysiology, epidemiology, and site-directed molecular and cellular interventions constitute the next generation of transformative advances in autoimmune hepatitis.

Evidence from a familial case suggests maternal inheritance of primary biliary cholangitis

Primary biliary cholangitis (PBC) is an idiopathic autoimmune liver disease characterized by chronic cholestasis and destruction of the intrahepatic bile ducts. Similar to other autoimmune diseases, the pathogenesis of PBC is considered to be a complex etiologic phenomenon involving the interaction of genetic and environmental factors. Although a number of common variants associated with PBC have been reported from genome-wide association studies, a precise genetic mechanism underlying PBC has yet to be identified. Here, we describe a family with four sisters who were diagnosed with PBC. After the diagnosis of the index patient who was in an advanced stage of PBC, one sister presented with acute hepatitis, and two sisters were subsequently diagnosed with PBC. Notably, one half-sister with a different mother exhibited no evidence of PBC following clinical investigation. Our report suggests the possibility of a maternal inheritance of PBC susceptibility. Moreover, judging from the high-penetrance of the disease observed in this family, we inferred that a pathogenic genetic variant might be the cause of PBC development. We describe a family that exhibited diverse clinical presentations of PBC that included asymptomatic stages with mildly increased liver enzyme levels and symptomatic stages with acute hepatitis or advanced liver fibrosis. Additional studies are needed to investigate the role of genetic factors in the pathogenesis of this rare autoimmune disease.

Global Disparities and Their Implications in the Occurrence and Outcome of Autoimmune Hepatitis

Autoimmune hepatitis has a variable occurrence, clinical phenotype, and outcome, and the factors contributing to this variability are uncertain. The goals of this review are to examine the global disparities in the occurrence and outcome of autoimmune hepatitis, suggest bases for these disparities, and encourage investigations that extend beyond single-center experiences. Disparities in the incidence and prevalence of autoimmune hepatitis in different age groups, genders, ethnicities, and geographical regions suggest that factors other than genetic predisposition are involved. Age- and gender-related antigen exposures from the external (infections, toxins, and medications) and internal (intestinal microbiome) environment may affect the incidence of the disease, and the timeliness and nature of treatment may influence its prevalence. The increasing incidence of autoimmune hepatitis in Spain, Denmark, and the Netherlands suggests that a new etiological trigger has been introduced or that the susceptible population has changed. Variations in mortality between Western and Asian-Pacific countries may result from differences in disease detection or management, and variations in gender predilection, peak age of onset, frequency of concurrent immune diseases, and serological profile may reflect gender-biased and age-related antigen exposures and genetic predispositions. Global collaborations, population-based epidemiological studies that identify case clustering, and controlled interview-based surveys are mechanisms by which to understand these disparities and improve management. In conclusion, autoimmune hepatitis has a rising incidence in some countries and variable occurrence, phenotype, and outcome between countries and subgroups within countries. These disparities suggest that unrecognized population-based environmental, infectious, or socioeconomic factors are affecting its character.

Hormonal contraception and the development of autoimmunity: A review of the literature

Estrogens and progestins are known to have profound effects on the immune system and may modulate the susceptibility to autoimmune diseases. A comprehensive literature search was carried out using PubMed for any of 153 autoimmune disease terms and the terms contraception, contraceptive, or their chemical components with limits of Humans + Title or Abstract. Over 1,800 titles were returned and scanned, 352 papers retrieved and reviewed in depth and an additional 70 papers retrieved from the bibliographies. Based on this review, substantial evidence exists linking the use of combined oral contraceptives to a lower incidence of hyperthyroidism, an increase in multiple sclerosis, ulcerative colitis, Crohn's disease, Systemic Lupus Erythematosus, and interstitial cystitis. Progesterone only contraceptives are linked to progesterone dermatitis and in one large developing world concurrent cohort study are associated with increases in arthropathies and related disorders, eczema and contact dermatitis, pruritis and related conditions, alopecia, acne, and urticaria. Hormonal contraceptives modulate the immune system and may influence the susceptibility to autoimmune diseases with significant increases in risk for several autoimmune diseases.

SUMMARY

Hormonal contraceptives (HCs), such as the "pill," Norplant, and vaginal rings, are very potent hormones that have effects on the immune system, which is made up of white blood cells and lymph nodes and normally defends the body against invading bacteria, viruses and parasites. This review looked at the association of HC use to the development of autoimmune diseases, where the immune system turns against the body and causes damage to organs. There is good evidence that HC use is associated with an increased risk of several serious autoimmune diseases such as Crohn's disease (which causes inflammation of the bowels), Lupus (which causes inflammation in many organs), and interstitial cystitis (which causes inflammation in the bladder). Several other rarer autoimmune diseases are also linked to HC use. People contemplating the use of HCs should be informed of these risks.

Geoepidemiology, clinical manifestations and outcome of primary biliary cholangitis in Greece

BACKGROUND & AIMS

Primary biliary cholangitis (PBC) is a disease with rising prevalence and considerable geographical variation. To describe the prevalence, spatial and time distribution, baseline characteristics, response to treatment, outcome and the validity of GLOBE score in a large cohort of Greek PBC patients as an independent validation of this score has not been done so far.

METHODS

The last 16years, 482 PBC patients (86.5% females) were evaluated and analysed retrospectively, using a prospectively collected database. Special attention was paid to the assessment of treatment response according to GLOBE score.

RESULTS

Age at initial evaluation was 56.3±13.7years. Among 432 Thessaly residents, prevalence was 582/million (non-homogeneous distribution). Nineteen districts showed a prevalence >800/million. Symptomatic disease onset could be identified in 91 patients, with a significant peak during spring (P=0.03). At diagnosis, 43.6% were asymptomatic and 16.2% cirrhotic. Male sex (P=0.02), older age (P<0.001), alcohol consumption (P<0.01) and concomitant liver disease (P<0.001) were negative prognostic factors for cirrhosis. During a median [interquartile range, range] follow-up of 5.1 (7.8, 15.7) years, 62 patients died or underwent liver transplantation. Patients with GLOBE score>0.30 had significantly worse prognosis (P<0.001) with 5-, 10-, and 15-year survival rates of 84%, 50% and 42%.

CONCLUSIONS

There is increased PBC prevalence in Thessaly with remarkable geographic clustering and seasonal variability. PBC is diagnosed at early stages although males had a more advanced disease. GLOBE score applies perfectly in Greek patients and this will likely help detecting patients that may benefit from new therapies.

Epigenetics in the Primary Biliary Cholangitis and Primary Sclerosing Cholangitis

Epigenomics, the study of modifications to genetic material that do not alter the underlying DNA sequence, is generating increasing interest as a means to help clarify disease pathogenesis and outcomes. Although genome-wide association studies have identified several potential candidate genes that may be implicated in primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), it is estimated that these genes explain less than 20% of the heritability of these diseases. Thus, to date, the origins of “missing heritability” for PBC and PSC remain elusive. The epigenome may provide a potentially elegant solution to this phenomenon, as it can be modified by both internal and external exposures (coined the “exposome”). This may explain differences in disease presentation, treatment response, and rates of progression between individuals. Epigenetic changes may also provide a framework for discovering potential biomarkers for diagnosis and screening of PBC and PSC. Importantly, because the epigenome is modifiable, it may also highlight novel pathways for therapeutic discovery and interventions of these diseases.

First-Degree Living-Related Donor Liver Transplantation in Autoimmune Liver Diseases

Liver transplantation (LT) is the treatment of choice for end-stage autoimmune liver diseases. However, the underlying disease may recur in the graft in some 20% of cases. The aim of this study is to determine whether LT using living donor grafts from first-degree relatives results in higher rates of recurrence than grafts from more distant/unrelated donors. Two hundred sixty-three patients, who underwent a first LT in the Toronto liver transplant program between January 2000 and March 2015 for autoimmune liver diseases, and had at least 6 months of post-LT follow-up, were included in this study. Of these, 72 (27%) received a graft from a first-degree living-related donor, 56 (21%) from a distant/unrelated living donor, and 135 (51%) from a deceased donor for primary sclerosing cholangitis (PSC) (n = 138, 52%), primary biliary cholangitis (PBC) (n = 69, 26%), autoimmune hepatitis (AIH) (n = 44, 17%), and overlap syndromes (n = 12, 5%). Recurrence occurred in 52 (20%) patients. Recurrence rates for each autoimmune liver disease were not significantly different after first-degree living-related, living-unrelated, or deceased-donor LT. Similarly, time to recurrence, recurrence-related graft failure, graft survival, and patient survival were not significantly different between groups. In conclusion, first-degree living-related donor LT for PSC, PBC, or AIH is not associated with an increased risk of disease recurrence.

Primary Biliary Cholangitis: Disease Pathogenesis and Implications for Established and Novel Therapeutics

Primary Biliary Cholangitis is a progressive, autoimmune cholestatic liver disorder. Cholestasis with disease progression may lead to dyslipidemia, osteodystrophy and fat-soluble vitamin deficiency. Portal hypertension may develop prior to advanced stages of fibrosis. Untreated disease may lead to cirrhosis, hepatocellular cancer and need for orthotopic liver transplantation. Classically, diagnosis is made with elevation of alkaline phosphatase, demonstration of circulating antimitochondrial antibody, and if performed: asymmetric destruction/nonsupperative cholangitis of intralobular bile ducts on biopsy. Disease pathogenesis is complex and results from innate and adaptive (cell-mediated and humoral) responses that lead to inflammation of biliary duct epithelium. Ongoing damage is amplified and sustained through bile acid toxicity. Use of weight based (13-15mg/kg) ursodeoxycholic acid is well established in retarding disease progression and improving survival; however, is ineffective in achieving complete biochemical remission in many. Recently, a Farnesoid X Receptor agonist, obeticholic acid, has been approved for use. A number of ongoing clinical studies are underway to evaluate utility of fibric acid derivatives, biologics, antifibrotics, and stem cells as monotherapy or in combination with ursodeoxycholic acid for primary biliary cholangitis. The aim of this review is to discuss disease pathogenesis and highlight rationale/implications for both established and novel therapeutics.

Impact of Microbes on the Pathogenesis of Primary Biliary Cirrhosis (PBC) and Primary Sclerosing Cholangitis (PSC)

Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) represent the major clinical entities of chronic cholestatic liver diseases. Both disorders are characterized by portal inflammation and slowly progress to obliterative fibrosis and eventually liver cirrhosis. Although immune-pathogenic mechanisms have been implicated in the pathogenesis of PBC and PSC, neither disorder is considered to be a classical autoimmune disease, as PSC and PBC patients do not respond to immune-suppressants. Furthermore, the decreased bile flow resulting from the immune-mediated tissue assault and the subsequent accumulation of toxic bile products in PBC and PSC not only perpetuates biliary epithelial damage, but also alters the composition of the intestinal and biliary microbiota and its mutual interactions with the host. Consistent with the close association of PSC and inflammatory bowel disease (IBD), the polyclonal hyper IgM response in PBC and (auto-)antibodies which cross-react to microbial antigens in both diseases, an expansion of individual microbes leads to shifts in the composition of the intestinal or biliary microbiota and a subsequent altered integrity of epithelial layers, promoting microbial translocation. These changes have been implicated in the pathogenesis of both devastating disorders. Thus, we will discuss here these recent findings in the context of novel and alternative therapeutic options.

Morbidity and Mortality in 7,684 Women According to Personal Hair Dye Use: The Copenhagen City Heart Study followed for 37 Years

Background

Permanent hair dye contains aromatic amines which are carcinogenic, and can cause allergic skin reactions. In the long term personal use of hair dye might therefore influence both morbidity and mortality.

Objectives

We tested the hypothesis that personal use of hair dye in women is associated with increased morbidity and mortality in the general population.

Methods

We included 7,684 women from the Copenhagen City Heart Study with information on the use of personal hair dye. We assessed the risk of cancer, skin diseases, other morbidities, and mortality during a median follow-up of 27 years (range 0–37).

Results

The multivariable adjusted hazard ratio for malignant melanoma in women with versus without personal use of hair dye was 2.07 (95% confidence interval 1.25–3.42). There was no increased risk of other cancer types. For other skin diseases and other major causes of morbidity we found no differences between the two groups, except for a minor excess of digestive diseases and increased risk of Parkinson’s disease among women using hair dye. Finally, we found no difference in all-cause mortality comparing women using personal hair dye or not. After correction for multiple comparisons, none of the results remained significant. However, in sensitivity analysis the excess risk of malignant melanoma remained increased with a hazard ratio of 2.58 (95%CI 1.33–5.03) among users of personal hair dye.

Conclusions

Personal use of hair dye does not have major influences on morbidity and mortality. Our finding of a 2-fold risk of malignant melanoma in women using hair dye is hypothesis generating.

The Immunogenetics of Autoimmune Cholestasis

The immune-mediated hepatobiliary diseases, primary biliary cirrhosis and primary sclerosing cholangitis are relatively rare, albeit and account for a significant amount of liver transplant activity and liver-related mortality globally. Precise disease mechanisms are yet to be described although a contributory role of genetic predisposition is firmly established. In addition to links with the major histocompatibility complex, a number of associations outside this region harbor additional loci which underscore the fundamental role of breaks in immune tolerance and mucosal immunogenicity in the pathogenesis of autoimmune biliary disease. We provide an overview of these key discoveries before discussing putative avenues of therapeutic exploitation based on existing findings.

Population-based epidemiology of primary biliary cirrhosis in South Korea

BACKGROUND

As a rare disease, only a few population-based epidemiology studies of primary biliary cirrhosis (PBC) have been reported.

AIMS

To elucidate the nationwide prevalence, incidence, complications, fatality and direct medical costs of PBC in South Korea.

METHODS

The nationwide Health Insurance Review and Assessment Service claims data and Rare Intractable Disease registration data on PBC, identified with the International Classification of Diseases (ICD) 10 code of K74.3, were obtained from 2009 to 2013. Age- and gender-specific prevalence and incidence rates of PBC were calculated, and data on complications, comorbidities, prescribed drugs, therapeutic procedures and direct medical costs were analysed.

RESULTS

A total of 2824 patients over 20 years old with PBC were identified in 2009-2013 (female-to-male ratio 6.2, median age 57 years old). The average age- and sex-adjusted incidence from 2011 to 2013 was 8.57 per million per year, and the average age- and sex-adjusted prevalence from 2009 to 2013 was 47.50 per million population. About 10% of patients presented with complications such as ascites (10.3%), variceal bleeding (5.8%) and/or hepatocellular carcinoma (HCC) (1.3%). Liver transplantation was undertaken in 71 patients (2.5%) for 5 years. Case fatality was 2.2% and the transplantation-free survival was 95.4% for 5 years.

CONCLUSIONS

This is the first report on the nationwide epidemiology of primary biliary cirrhosis in South Korea, demonstrating lower incidence and prevalence rates than those of Western countries, but a considerable disease burden, representing at least 10% were complicated with decompensated cirrhosis or hepatocellular carcinoma requiring liver transplantation.

Women and primary biliary cirrhosis

Primary biliary cirrhosis occurs more frequently in women, and previous studies indicated that the average age of primary biliary cirrhosis (PBC) onset makes pregnancy in PBC patients uncommon. However, more recently, improved diagnostic testing has enabled detection of PBC in younger women, including those of childbearing age. This has led investigators to become increasingly interested in the relationship between the ontogeny of PBC and pregnancy. Published cases indicate that the typical age for pregnant women to be diagnosed with PBC is in the early 30s, and that during gestation, pruritus and jaundice are the most common symptoms. During gestation, susceptible women may experience onset of PBC resulting from the drastic changes in female hormones; this would include not only the mitochondrial damage due to accumulation of bile acids but also changes in the immune response during the different stages of pregnancy that might play an important role in the breakdown of self-tolerance. The mechanisms underlying the potential relationship between PBC and pregnancy warrant further investigation. For women first diagnosed with PBC during gestation, or those for whom first appearance of a flare up occurs during and postpartum, investigation of the immune response throughout gestation could provide new avenues for immunologic therapeutic intervention and the discovery of new treatment strategies for PBC.

Primary biliary cirrhosis

Primary biliary cirrhosis is a chronic cholestatic liver disease characterised by destruction of small intrahepatic bile ducts, leading to fibrosis and potential cirrhosis through resulting complications. The serological hallmark of primary biliary cirrhosis is the antimitochondrial antibody, a highly disease-specific antibody identified in about 95% of patients with primary biliary cirrhosis. These patients usually have fatigue and pruritus, both of which occur independently of disease severity. The typical course of primary biliary cirrhosis has changed substantially with the introduöction of ursodeoxycholic acid (UDCA). Several randomised placebo-controlled studies have shown that UDCA improves transplant-free survival in primary biliary cirrhosis. However, about 40% of patients do not have a biochemical response to UDCA and would benefit from new therapies. Liver transplantation is a life-saving surgery with excellent outcomes for those with decompensated cirrhosis. Meanwhile, research on nuclear receptor hormones has led to the development of exciting new potential treatments. This Seminar will review the current understanding of the epidemiology, pathogenesis, and natural history of primary biliary cirrhosis, discuss management of the disease and its sequelae, and introduce research on new therapeutic options.

Primary biliary cirrhosis: From bench to bedside

Primary biliary cirrhosis (PBC) is a chronic non-suppurative destructive intrahepatic cholangitis leading to cirrhosis after a protractive non cirrhotic stage. The etiology and pathogenesis are largely unknown and autoimmne mechanisms have been implicated to explain the pathological lesions. Many epitopes and autoantigens have been reported as crucial in the pathophysiology of the disease and T and B cells abnormalities have been described, the exact pathways leading to the destruction of small intrahepatic ductules are mostly speculative. In this review we examined the various epidemiologal and geoepidemiological data as well as the complex pathogenetic aspects of this disease, focusing on recent in vivo and in vitro studies in this field. Initiation and progression of PBC is believed to be a multifactorial process with strong infuences from the patient’s genetic background and by various environmental factors. The role of innate and adaptive immunity, including cytokines, chemokines, macrophages and the involvement of apoptosis and reactive oxygen species are outlined in detailed. The current pathogenetic aspects are presented and a novel pathogenetic theory unifying the accumulated clinical information with in vitro and in vivo data is formulated. A review of clinical manifestations and immunological and pathological diagnosis was presented. Treatment modalities, including the multiple mechanisms of action of ursodeoxycholate were finally discussed.

Liver Transplantation for Patients with Cholestatic Liver Diseases

Background

Cholestatic liver diseases (CD) account for 11% of all liver transplantations (LT) in the Eurotransplant region. Despite the excellent long-term outcome that is considerably superior to all other indications for LT, transplant surgeons and physicians face nowadays – in the era of MELD (Model of End-Stage Liver Disease)-based allocation, organ shortage, and extended allocation policies – more and more challenges in this patient cohort, especially since there is no curative medical treatment for these entities.

Methods

Based on a literature review and personal experience in liver transplantation for CD, we show the status quo of indication, allocation, and outcome as well as potential strategies to overcome long waiting times and organ shortage.

Results

Concerning graft and patient survival, CD remain the ‘best indications’ for LT. Since the implementation of MELD-based allocation results in patients with primary sclerosing cholangitis (PSC) could be preserved on good levels only by the implementation and revision of standard exceptions. Recurrence of PSC after LT remains a challenge for transplant surgeons and physicians. New data has kindled a debate on biliary reconstruction in LT for PSC. Promising data on living donor LT motivate to push the boundaries in this direction.

Conclusion

CD are excellent indications for liver transplantation since excellent long-term outcomes are achievable when the transplant is performed at the right time. The decisions concerning evaluation, listing, and allocation should be made by an interdisciplinary team of gastroenterologists and transplant surgeons.

Biliary Mucosal Barrier and Microbiome

Background

The biliary system is in continuous contact with the complex microbiota of the intestine. Microbial products have recently been proposed as potential triggers for biliary diseases.

Methods

The aim of this review is to provide a summary of the current knowledge regarding the role of the biliary and intestinal microbiome in biliary inflammatory diseases.

Results

Previously, it was suggested that the healthy biliary system is a sterile organ, while acute cholangitis and cholecystitis may occur from ascending infections. Although non-inflammatory biliary colonization by certain bacteria such as Salmonella spp. has been already recognized since several decades, human and animal studies indicated only very recently that the gallbladder harbors a complex microbiota also under non-pathologic conditions. Novel findings suggested that – similar to the situation in the intestine – the biliary mucosa features a chemical, mechanical, and immunological barrier, ensuring immunological tolerance against commensals. However, microbial triggers might influence acute and chronic inflammatory disease of the biliary system and the whole liver.

Conclusion

Although yet undefined, dysbiosis of the biliary or intestinal microbiota rather than a single microorganism may influence disease progression.