Primary biliary cirrhosis: a 2010 update

Comorbidities, mortality and metabolic profile in individuals with primary biliary cholangitis-A Phenome-Wide-Association-Study

BACKGROUND AND AIMS

Primary biliary cholangitis (PBC) is a chronic, immune-mediated liver disease that can lead to fibrosis and cirrhosis. In this cohort study, we aimed to investigate morbidity and mortality in conjunction with metabolomic changes of PBC in a UK population-based cohort.

METHODS

454 participants with PBC and 908 propensity score (age, sex, BMI, ethnicity) matched controls without liver disease were included in the study. A subset of participants with PBC and controls were analysed for their metabolomic profile. Further, PBC-associated comorbidities were investigated by PheWAS analysis. Lastly, we assessed causes of death in individuals with PBC using a Fine and Grey competing-risks regression model.

RESULTS

Compared to the control group, various pathways associated with the metabolism of amino acids, lipids, and liver biochemistry were significantly enriched in individuals with PBC. We found reduced levels of S-HDL-cholesterol and Glycoprotein Acetyls in individuals with PBC as well as an association with diseases of the circulatory system. Notably, PBC individuals had a higher prevalence of digestive diseases, autoimmune diseases, cardiovascular diseases, anaemias, mental disorders, and urinary tract infections compared to the control group. Strikingly, the overall mortality was almost three times higher in the PBC group compared to the control group, with diseases of the digestive system accounting for a significant elevation of the death rate. A subsequent analysis, enhanced by propensity score matching that included the APRI score, demonstrated that the observed morbidity could not be exclusively attributed to advanced hepatic disease.

CONCLUSIONS

Our study provides a detailed perspective on the morbidity of individuals with PBC. The exploration of potential effects of disease state on morbidity suggest that early detection and early treatment of PBC could enhance patient prognosis and prevent the onset of comorbid diseases. Finally, the metabolomic alterations could represent a link between the pathophysiological processes underlying PBC development, progression, and associated morbidity.

Longitudinal outcomes of obeticholic acid therapy in ursodiol-nonresponsive primary biliary cholangitis: Stratifying the impact of add-on fibrates in real-world practice

BACKGROUND

Suboptimal response to ursodeoxycholic acid occurs in 40% of primary biliary cholangitis (PBC) patients, affecting survival. Achieving a deep response (normalisation of alkaline phosphatase [ALP] and bilirubin ≤0.6 upper limit of normal) improves survival. Yet, the long-term effectiveness of second-line treatments remains uncertain.

AIMS

To evaluate the long-term effectiveness of obeticholic acid (OCA) ± fibrates. Focusing on biochemical response (ALP ≤1.67 times the upper limit of normal, with a decrease of at least 15% from baseline and normal bilirubin levels), normalisation of ALP, deep response and biochemical remission (deep response plus aminotransferase normalisation).

METHODS

We conducted a longitudinal, observational, multicentre study involving ursodeoxyccholic acid non-responsive PBC patients (Paris-II criteria) from Spain and Portugal who received OCA ± fibrates.

RESULTS

Of 255 patients, median follow-up was 35.1 months (IQR: 20.2-53). The biochemical response in the whole cohort was 47.2%, 61.4% and 68.6% at 12, 24 and 36 months. GLOBE-PBC and 5-year UK-PBC scores improved (p < 0.001). Triple therapy (ursodeoxycholic acid plus OCA plus fibrates) had significantly higher response rates than dual therapy (p = 0.001), including ALP normalisation, deep response and biochemical remission (p < 0.001). In multivariate analysis, triple therapy remained independently associated with biochemical response (p = 0.024), alkaline phosphatase normalisation, deep response and biochemical remission (p < 0.001). Adverse effects occurred in 41.2% of cases, leading to 18.8% discontinuing OCA. Out of 55 patients with cirrhosis, 12 developed decompensation. All with baseline portal hypertension.

CONCLUSION

Triple therapy was superior in achieving therapeutic goals in UDCA-nonresponsive PBC. Decompensation was linked to pre-existing portal hypertension.

Evolutionary relationship between antimitochondrial antibody positivity and primary biliary cholangitis in Taiwan: a 16-year hospital cohort study

Background

How antimitochondrial antibody (AMA)-positive patients evolve to have primary biliary cholangitis (PBC) in viral hepatitis-endemic areas is unknown.

Objectives

We aimed to investigate this evolution in Taiwan.

Design/methods

A 16-year medical center-based cohort study of 2,095,628 subjects was conducted in Taiwan, an Asian country endemic to viral hepatitis. AMA-positive subjects were those with positive AMA with alkaline phosphatase (ALP) ⩽1.5 times the upper limit of normal (ULN), and PBC was defined as positive AMA with ALP >1.5 × ULN.

Results

AMA-positive subjects had a lower average age- and sex-adjusted prevalence than PBC patients (4.68/105 versus 11.61/105, p = 0.0002), but their incidence was comparable (0.99/105 versus 1.12/105, p = 0.36). The former group had a borderline significantly lower mean age (56.59 years versus 58.10 years, p = 0.06) and a lower female-to-male ratio (2.85:1 versus 5.44:1, p < 0.0001). Both AMA-positive subjects (prevalence change: 20.0%, p < 0.01; incidence change: -9.2%, p < 0.01) and PBC patients (prevalence change: 14.6%, p < 0.01; incidence change: -4.7%, p < 0.01) prevalence rate increased but the incidence rate decreased. Among the 423 AMA-positive subjects, 77 (18.2%) developed PBC, for a mean duration of 1.757 years. Compared with AMA-positive subjects, PBC patients had similar concurrent chronic hepatitis B (CHB) rates (2.7% versus 4.3%, p = 0.197) but lower chronic hepatitis C (CHC) rates (3.69% versus 15.60%, p < 0.01).

Conclusion

PBC was more prevalent than AMA-positive subjects, and PBC patients had a higher female-to-male ratio than AMA-positive subjects, of whom 18.2% developed PBC (mean lag: 1.757 years). Upward trends in prevalence rates and downward trends in incidence rates were noted for both AMA-positive subjects and PBC. CHB was rare, CHC was more prevalent among PBC patients than the general population, and CHC was less prevalent among PBC than among AMA-positive subjects.

Treatment of Primary Biliary Cholangitis including Transplantation

Ursodeoxycholic acid (UDCA) is the first-line treatment of primary biliary cholangitis (PBC). Long-term UDCA use significantly reduces progression to cirrhosis. UDCA improves liver enzymes and transplant-free survival rates. Despite the association between PBC and hyperlipidemia, treatment is indicated under specific circumstances with statins and fibrates being safe options. Osteoporosis, which is frequently seen, is usually managed based on data from postmenopausal women. Sicca syndrome is treated similarly to its standalone condition with the use of hydroxypropyl methylcellulose eye drops and anticholinergic drugs.

Prevalence and clinicopathological Spectrum of Auto-Immune Liver Diseases & Overlap syndrome

Aims

Autoimmune liver diseases (AILD) represent a spectrum of related yet distinct immune-mediated disorders. The literature on the prevalence of these AILDs in Indian population is scarce. This study aims to assess the prevalence and clinicopathological spectrum of various AILDs especially the overlap syndrome.

Materials and Methods

A 10-year (2011-2020) cross-sectional, retrospective observational study of histological proven cases of AILD was conducted. Clinical, demographic, and laboratory parameters were retrieved. Two pathologists independently reviewed the liver biopsies and reassessed 18 histopathological parameters.

Results

During the study period, 17664 liver biopsies were received, out of which 1060 (6%) biopsies of AILD were identified. After exclusion, we had 721 cases which revealed a distribution of autoimmune hepatitis (AIH)-64.7%, primary biliary cholangitis (PBC)-14.8%, primary sclerosing cholangitis (PSC)-7.6%, overlap AIH-PBC 11%, and overlap AIH-PSC 1.7%. AIH patients had significantly higher prevalence for severe lobular inflammation (27%, P ≤ 0.001), several lobular plasma cells (37%, P ≤ 0.001), central perivenulitis (30%, P ≤ 0.001), hepatic rosettes (51%, P ≤ 0.001), and necrosis (35.5%, P ≤ 0.001), while PBC patients had significantly higher frequency of florid duct lesions (11.2%, P ≤ 0.001), duct loss (83.17%, P ≤ 0.001), bile duct damage (76.6%, P ≤ 0.001), and periportal copper deposits (19.6%, P ≤ 0.001). Overlap AIH-PBC group had the highest proportion of severe portal inflammation (27.5%, P ≤ 0.001), prominent portal plasma cells (75%, P ≤ 0.001), moderate interface activity (53.7%, P ≤ 0.001), Mallory-Denk bodies (27.5%, P ≤ 0.001), and periportal cholate stasis (25%, P ≤ 0.001).

Conclusion

Prevalence of biopsy-proven AILDs in our study cohort is 6%. AIH (64.7%) is the most common AILD followed by PBC (14.8%). Overlap syndrome (AIH-PBC) showed prevalence of 11%.

Clinical significance of serum antinuclear antibodies in patients with autoimmune hepatitis and comorbidity

Autoimmune hepatitis (AIH) is often complicated with immune diseases, which greatly affected the course and clinical outcome of AIH. We aimed to systematically assess clinical characteristics, prognosis in autoimmune hepatitis accompanied by immune diseases. Clinical records of 358 patients with AIH from Beijing Ditan Hospital in China were retrospectively reviewed. The clinical features of AIH with immune diseases were compared retrospectively, including clinical characteristics, prognosis and outcome. Prevalence of immune diseases in patients with AIH was 26.5%. Connective tissue disease (CTD) was the commonest immune diseases associated with AIH (33/358, 9.2%), and the incidence of primary biliary cholangitis (PBC) and thyroid dysfunction (TD) was low (4.7% and 8.5%, respectively). At diagnosis, AIH-PBC patients had higher IgM and ALP, lower weight, Hgb, ALT and AFP (P < 0.05). Meanwhile, AIH-CTD patients had lower mean platelet volume, serum K and triglyceride (P < 0.05). AIH-TD patients had a lower proportion of ANA positive (P < 0.05). The overall survival time of AIH-TD was significantly shorter than AIH patients (P = 0.0011), but there were no differences in AIH-PBC and AIH-CTD. Furthermore, ANA negative (HR: 0.21, 95%CI 0.13-0.35, P < 0.001) can be a factor to predict the poor prognosis of AIH, and also in AIH-TD patients. About 26.5% of AIH patients had at least one immune disease, and TD coexisted with AIH impaired patients' survival. ANA negative can be used as an independent indicator to predict the poor prognosis of AIH and AIH-TD.

Bioinformatic analysis identified novel candidate genes with the potentials for diagnostic blood testing of primary biliary cholangitis

Primary biliary cholangitis (PBC) is an autoimmune disorder characterized by intrahepatic bile duct destruction and cholestatic liver injury. Diagnosis of PBC is generally based on the existence of anti-mitochondrial antibody (AMA) in blood samples; however, some PBC patients are negative for serum AMA tests, and invasive liver histological testing is required in rare PBC cases. The current study seeks novel candidate genes that are associated with PBC status and have potentials for blood diagnostic testing. Human transcriptomic profiling data of liver and blood samples were obtained from Gene Expression Omnibus (GEO). Three GEO data series (GSE79850, GSE159676, and GSE119600) were downloaded, and bioinformatic analyses were performed. Various differentially expressed genes were identified in three data series by comparing PBC patients and control individuals. Twelve candidate genes were identified, which were upregulated in both liver tissues and blood samples of PBC patients in all three data series. The enrichment analysis demonstrated that 8 out of 12 candidate genes were associated with biological functions, which were closely related to autoimmune diseases including PBC. Candidate genes, especially ITGAL showed good potentials to distinguish PBC with other diseases. These candidate genes could be useful for diagnostic blood testing of PBC, although further clinical studies are required to evaluate their potentials as diagnostic biomarkers.

Novel HLA allele associations with susceptibility, staging, symptomatic state, autoimmune hepatitis and hepatocellular carcinoma events for primary biliary cholangitis in the Japanese population

Primary biliary cholangitis (PBC) is a rare autoimmune disease with a clear predisposition for human leukocyte antigen (HLA)-DR/DQ-associated loss of immune tolerance for the E2 component of the pyruvate dehydrogenase complex. Three-field-resolution HLA imputation of 1,670 Japanese PBC patients and 2,328 healthy controls was conducted using Japanese population-specific HLA reference panels. Eighteen previously reported Japanese PBC-associated HLA alleles were confirmed and extended to 3-field-resolution, including HLA-DRB1*08:03 to HLA-DRB1*08:03:02, HLA-DQB1*03:01 to HLA-DQB1*03:01:01, HLA-DQB1*04:01 to HLA-DQB1*04:01:01 and HLA-DQB1*06:04 to HLA-DQB1*06:04:01. In addition, additional significant novel HLA alleles were identified, including 3 novel susceptible HLA-DQA1 alleles: HLA-DQA1*03:03:01, HLA-DQA1*04:01:01, HLA-DQA1*01:04:01 and 1 novel protective HLA-DQA1 allele, HLA-DQA1*05:05:01. In addition, PBC patients carrying HLA-DRB1*15:01:01 and HLA-DQA1*03:03:01 would have a higher predisposition toward developing concomitant autoimmune hepatitis (AIH). Further, late-stage and symptomatic PBC shared the same susceptible HLA alleles of HLA-A*26:01:01, HLA-DRB1*09:01:02 and HLA-DQB1*03:03:02. Lastly, HLA-DPB1*05:01:01 was identified as a potential risk HLA allele for development of hepatocellular carcinoma (HCC) in PBC patients. In conclusion, we have extended the current knowledge of HLA allele associations to 3-field resolution and identified novel HLA allele associations with predisposition risk, staging, symptomatic state, and AIH and HCC events for Japanese PBC patients.

Systemic sclerosis and primary biliary cholangitis share an antibody population with identical specificity

Anti-centromere (ACA) and antimitochondrial antibodies (AMA) are specific for limited-cutaneous systemic sclerosis (lcSSc) and primary biliary cholangitis (PBC), respectively, and can coexist in up to 25 and 30% of SSc and PBC patients. Here, we evaluated whether anti-centromeric protein A (CENP-A) antibodies cross-react with mitochondrial antigens. To this end, sera from two lcSSc patients (pt1 and pt4), one of them (pt4) also affected by PBC, were used as the source of ACA, previously shown to recognize different groups of amino acids (motifs) in the CENP-A region spanning amino acids 1-17 (Ap1-17). Pt1 and pt4 Ap1-17-specific IgG were purified by affinity-chromatography on insolubilized Ap1-17-peptide column and tested by western blotting with nuclear and cytoplasmic protein extract from HeLa cells. Immunoreactive proteins were identified by mass spectrometry and validated by immunodot. The results showed that affinity-purified SSc/PBC pt4 anti-Ap1-17 and not SSc pt1 anti-Ap1-17 Ab, specifically cross-reacted with the E2 component of the mitochondrial pyruvate dehydrogenase complex (PDC-E2), the major mitochondrial autoantigen in PBC. Sequence homology analysis indicated that the motif A-x-x-P-x-A-P recognized by pt4 anti-Ap1-17 IgG and shared by CENP-A and PDC-E2, is also expressed by some members of the Human Herpesvirus family, suggesting that they may trigger the production of these cross-reacting antibodies.

Post-Transplant Immunosuppression in Autoimmune Liver Disease

Autoimmune liver diseases (AILDs) are a group of conditions where immune-mediated liver damage can lead to the need for transplantation. Collectively, they account for almost a quarter of all liver transplants. Outcomes in terms of graft and patient survival for all liver transplants have improved markedly over decades with improvements in patient selection, surgical techniques and longer-term care and this is also seen in patients with AILDs. The current five- and ten-year survival rates post-transplant in autoimmune disease are excellent, at 88% and 78%, respectively. A key factor in maintaining good outcomes post liver transplant for these autoimmune conditions is the immunosuppression strategy. These patients have increased the rates of rejection, and autoimmune conditions can all recur in the graft ranging from 12 to 60% depending on the population studied. Immunosuppressive regimens are centred on calcineurin inhibitors, often combined with low dose corticosteroids, with or without the addition of antimetabolite therapy. There is no clear evidence-based immunosuppressive regimen for these conditions, and a tailored approach balancing the individuals' immunological profile against the risks of immunosuppression is often used. There are disease-specific considerations to optimised graft function including the role of ursodeoxycholic acid in both primary biliary cholangitis and primary sclerosing cholangitis and the role and timing of colectomy in primary sclerosing cholangitis in inflammatory bowel disease patients. However, unmet needs still exist in the management of AILDs post liver transplantation particularly in building the evidence base for optimal immunosuppression as well as mitigating the risk of recurrent disease.

Treatment of ursodeoxycholic acid with glucocorticoids and immunosuppressants may improve the long-term survival rate in primary biliary cholangitis patients

Primary biliary cholangitis (PBC) is an autoimmune cholestatic liver disease. The clinical effectiveness of ursodeoxycholic acid (UDCA) plus glucocorticoids and/or immunosuppressants remains controversial in PBC patients. The study aimed to compare the efficacy of monotherapy and combination therapy in patients with PBC and to assess the factors affecting the efficacy. In this retrospective study, 266 patients diagnosed with PBC were divided into monotherapy group (UDCA), double therapy group (UDCA plus glucocorticoids or immunosuppressants), and triple therapy group (UDCA plus glucocorticoids and immunosuppressants) according to different treatments. Demographic characteristics, immune parameters, biochemistry profiles, and other indicators were evaluated at baseline, 6 months, and 1 year following treatment. The prognosis was evaluated using the Paris II standard. The liver transplant-free survival at 3, 5, 10, and 15 years was predicted by GLOBE score. All statistical analyses were conducted using SPSS (version 24) software (SPSS Inc, Chicago, IL). The long-term survival rate of the triple therapy group was significantly improved compared with the monotherapy group (P = .005). In addition, multivariate analysis showed that abnormal platelet count, alkaline phosphatase, and albumin levels were risk factors for poor response. When IgG levels were elevated but below twice the upper limit of normal, the clinical benefit was not significant compared with monotherapy (P > .05). Compared with monotherapy and double therapy, triple therapy may improve the long-term survival rate of PBC patients. Abnormal platelet count, alkaline phosphatase, and albumin levels were associated with a poor prognosis.

Pretransplant Evaluation and Liver Transplantation Outcome in PBC Patients

Primary biliary cholangitis (PBC) is an autoimmune chronic cholestatic liver disease characterized by progressive cholangiocyte and bile duct destruction leading to fibrosis and finally to liver cirrhosis. The presence of disease-specific serological antimitochondrial antibody (AMA) together with elevated alkaline phosphatase (ALP) as a biomarker of cholestasis is sufficient for diagnosis. Ursodeoxycholic acid (UDCA) is the first treatment option for PBC. Up to 40% of patients have an incomplete response to therapy, and over time disease progresses to liver cirrhosis. Several risk scores are proposed for better evaluation of patients before and during treatment to stratify patients at increased risk of disease progression. GLOBE score and UK PBC risk score are used for the evaluation of UDCA treatment and Mayo risk score for transplant-free survival. Liver transplantation (LT) is the only treatment option for end-stage liver disease. More than 10 years after LT, 40% of patients experience recurrence of the disease. A liver biopsy is required to establish rPBC (recurrent primary biliary cholangitis). The only treatment option for rPBC is UDCA, and data show biochemical and clinical improvement, plus potential beneficial effects for use after transplantation for the prevention of rPBC development. Additional studies are required to assess the full impact of rPBC on graft and recipient survival and for treatment options for rPBC.

Roles of Non-Coding RNAs in Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is an autoimmune-mediated chronic cholestatic liver disease, fatigue, and skin itching are the most common clinical symptoms. Its main pathological feature is the progressive damage and destruction of bile duct epithelial cells. Non-coding RNA (NcRNA, mainly including microRNA, long non-coding RNA and circular RNA) plays a role in the pathological and biological processes of various diseases, especially autoimmune diseases. Many validated ncRNAs are expected to be biomarkers for the diagnosis or treatment of PBC. This review will elucidate the pathogenesis of PBC and help to identify potential ncRNA biomarkers for PBC.

Downregulation of Programmed Death-1 Pathway Promoting CD8 + T Cell Cytotoxicity in Primary Biliary Cholangitis

BACKGROUND

Primary biliary cholangitis (PBC) is an autoimmune disease. CD8 + T cell (CTLs) cytotoxicity played a crucial rule in of PBC with unclear detailed pathogenesis.

AIMS

The role of the programmed death-1 (PD-1) pathway in CD8 + T cell cytotoxicity in patients with PBC was determined.

METHODS

We recruited 69 patients with PBC and 57 healthy controls (HCs). PD-1 pathway in peripheral CD8 + T cells and related cytokines were detected, and gene expression levels were detected. Immunofluorescence staining of PD-1/PD-L1 was performed on liver tissue. PD-1 ± CTLs were cocultured with human intrahepatic biliary epithelial cells (HiBECs) to measure CTL cytotoxicity, proliferation and cytokine levels and HiBEC apoptosis. The upstream signaling pathway of PD-1 was detected.

RESULTS

PBC patients exhibited Tbet gene upregulation and PD-1 downregulation in CTLs, with PD-1 expression reduced in CTLs and PD-L1 reduced in the liver portal region relative to HCs. Higher plasma IL-10, interferon-γ and transforming growth factor-β concentrations were observed in the PBC group than the HC group. In CTL and HiBEC coculture experiment, compared with PD-1- CTLs, PD-1 + CTLs exhibited weaker cytotoxicity, less proliferation and lower cytokine production. When the system was blocked by anti-PD-1 antibodies, these effects were antagonized.

CONCLUSIONS

PD-1 expression in CD8 + T cells decreased, and PD-1 pathway-related cytokines changed in patients with PBC. PD-1/PD-L1 pathway silencing increased CD8 + T cell proliferation, related cytokine production and CTL cytotoxic effects on HiBECs in coculture experiment. The PD-1/PD-L1 pathway might represent an important pathway in the immunological mechanism underlying PBC.

Arrival-Time Parametric Imaging in Contrast-Enhanced Ultrasound for Diagnosing Fibrosis in Primary Biliary Cholangitis

Liver biopsy is usually required for diagnosing fibrosis in primary biliary cholangitis (PBC), but contrast-enhanced ultrasonography (CEUS) is a possible alternative. The aim of this study was to investigate arrival-time parametric imaging (At-PI) in for diagnosing fibrosis in PBC. Forty-eight patients (male/female, 8/40; mean age, 60 ± 13 years) with PBC diagnosed by liver biopsy underwent CEUS during 2009-2019. Of these, 27 who also underwent shear wave elastography (SWE) were further analyzed. Perflubutane was intravenously injected and CEUS performed. Contrast dynamics of hepatic segment V and the right kidney were recorded and At-PI generated. The ratio of red indicating contrast arrival time <5 seconds to the entire liver contrast-enhanced area was calculated and compared with shear wave velocity (Vs) measured by SWE by fibrosis stage (F0-F3), bile duct loss score, cholangitis activity, hepatitis activity (HA0-HA3), and disease stage, as determined by liver biopsy. Ratio of red significantly differed between F0 and F2-F3 and between F1 and F2-F3. Using ratio of red to diagnose ≥F1 (≥F2), area under the receiver operating characteristic curve was 0.77 (0.92) (cutoff, 36.7% [47.1%]; sensitivity, 0.75 [0.92]; specificity, 0.82 [0.81]). At-PI was useful for diagnosing fibrosis, especially F2 or worse, in PBC, suggesting that At-PI can correctly diagnose fibrosis regardless of hepatic inflammation.

Early histopathologic changes in primary biliary cholangitis: does 'minimal change' primary biliary cholangitis exist? A pathologist's view

Primary biliary cholangitis (PBC), formerly known as primary biliary cirrhosis, is an autoimmune, slowly progressive, cholestatic liver disease characterized by nonsuppurative destructive cholangitis, and interlobular bile duct destruction. Necroinflammatory activities of the hepatic parenchyma and limiting plates of milder form along with late liver fibrosis may develop. Serum liver tests include elevated serum alkaline phosphatase along with a positive antimitochondrial antibody (AMA) in nearly 95% of patients. Liver biopsies are an important confirmatory and staging tool and are additionally very helpful when AMA is negative. More specifically, the earliest changes in liver biopsy suspicious for PBC can be detected, namely loss of the canals of Hering (CoH), as proposed by various authors recently. CoH loss has been described as an early feature of PBC. We focus on early histologic features of PBC, investigating through the literature the possible role of 'minimal change' supporting the clinical diagnosis of PBC, even in the absence of characteristic granulomatous duct destructive lesions.

A Comparison of Prognostic Scores (Mayo, UK-PBC, and GLOBE) in Primary Biliary Cholangitis

INTRODUCTION

Comparative data on scores that predict outcome in primary biliary cholangitis (PBC) are scarce. We aimed to assess and compare the prognostic value of the Mayo Risk Score (MRS, 1989 and 1994), UK-PBC score, and GLOBE score in a large international cohort of patients with PBC.

METHODS

Ursodeoxycholic acid-treated patients from 7 centers participating in the GLOBAL PBC Study Group were included. The discriminatory performance of the scores was assessed with concordance statistics at yearly intervals up to 5 years. Model for End-stage Liver Disease was included for comparison. Prediction accuracy was assessed by comparing predicted survival and actual survival in Kaplan-Meier analyses.

RESULTS

A total of 1,100 ursodeoxycholic acid-treated patients with PBC were included, with a mean (SD) age of 53.6 (12.0) years, of whom 1,003 (91%) were female. During a median follow-up of 7.6 (interquartile range 4.1-11.7) years, 42 patients underwent liver transplantation, and 127 patients died. At 1 year, the concordance statistic for Model for End-stage Liver Disease was 0.68 (95% confidence interval [CI] 0.64-0.72), 0.74 (95% CI 0.67-0.80) for the UK-PBC score, 0.76 (95% CI 0.72-0.81) for the MRS (1989 and 1994), and 0.80 (95% CI 0.76-0.84) for the GLOBE score. The GLOBE score showed superior discriminatory performance, but differences were not statistically different. For all scores, discriminatory performance increased in those with bilirubin >0.6 × ULN and advanced fibrosis estimated with Fibrosis-4. The predicted (median) minus observed 5-year transplant-free survival was +0.4% and +2.5% for the MRS (1989) and GLOBE score, respectively.

DISCUSSION

All prognostic scores developed for PBC (GLOBE, UK-PBC, and MRS) demonstrated comparable discriminating performance for liver transplantation or death as well as good prediction accuracy.

Identification of the Representative Primary Biliary Cholangitis Cohort in Taiwan: A Comparison of Four Nationwide Cohorts

BACKGROUND/PURPOSE

The rates and outcomes of primary biliary cholangitis (PBC) in Taiwan remain unclear.

METHODS

A nationwide population-based cohort study (Taiwan National Health Insurance Research Database, 2002-2015) was conducted. Data from four PBC cohorts with various definitions were compared (cohort 1 (C1): ICD-9-CM (571.6); C2: alkaline phosphatase (Alk-P) and antimitochondrial antibody (AMA) measurements; C3: Alk-p and AMA measurements and ursodeoxycholic acid (UDCA) treatment; C4: ICD-9-CM (571.6), Alk-p and AMA measurements and UDCA treatment).

RESULTS

The average prevalence rate ranged from 9.419/10⁵ (C4) to 307.658/10⁵ (C2), and the female-to-male ratio ranged from 1.192 (C1) to 3.66 (C4). Prevalence rates increased over time in all cohorts. The average incidence rates ranged from 1.456/10⁵ (C4) to 66.386/10⁵ (C2). Incidence rates decreased over time in C1 (-9.09%, p < 0.0001) and C4 (-6.68%, p < 0.0001) and remained steady in the others. C4 had the lowest prevalence and incidence rates and highest female-to-male ratio. Cirrhosis rates ranged from 7.21% (C2) to 39.34% (C4), hepatoma rates ranged from 2.77%(C2) to 6.66%(C1), liver transplantation (LT) rates ranged from 1.07% (C2) to 6.77% (C4), and mortality rates ranged from 18.24% (C2) to 47.36% (C1). C4 had the highest LT (6.77%), osteoporosis (13.87%) and dyslipidemia rates (17.21%).

CONCLUSIONS

Based on the reported ranges of reasonable rates, female predominance and characteristic outcomes, C4 was the most representative Taiwanese PBC cohort, with average prevalence and incidence rates of 9.419/10⁵ and 1.456/10⁵, respectively, and a female-to-male ratio of 3.66. In a 14-year period, cirrhosis, hepatoma, LT, and mortality were noted in 39.34%, 5.52%, 6.77%, and 34.22% of C4 patients, respectively.

Gender and Racial Differences in Hospitalizations for Primary Biliary Cholangitis in the USA

BACKGROUND/AIM

The prevalence, characteristics, burden and trends of primary biliary cholangitis (PBC) hospitalizations in the USA remain unclear.

METHOD

We identified primary PBC hospitalizations from the National Inpatient Sample (NIS) 2007 through 2014 using ICD-9-CM codes. We calculated the rates and trends of hospitalization for PBC per 100,000 US population among each gender (males and females) and racial categories (Whites, Blacks, Hispanics and other racial minorities), and measured the predictors of hospitalization, and of mortality, charges and length of stay (LOS) among PBC hospitalizations.

RESULT

There were 8460 (weighted: 41,191) PBC hospitalizations between 2007 and 2014. The mean national PBC hospitalization rate was 2.2 cases per 100,000 population (2.2/100,000), increasing from 1.7/100,000 (2007) to 2.5/100,000 (2014). From 2007 to 2014, the in-hospital mortality and LOS were unchanged while the charges increased from $65,993 to $73,093 ($225 million to $447 million overall expenses). Compared to Whites, the PBC hospitalization rate was 12% higher among Hispanics (RR: 1.12 [1.09-1.16]), 53% lower in Blacks (RR: 0.47 [0.45-0.49]) and 5% lower among other racial minorities (0.95 [0.91-0.99]). The rate was higher among females (RR:4.02 [3.93-4.12]) compared to males. On multivariate analysis, Blacks and other racial minorities, respectively, had higher odds of mortality (AOR: 1.47 [1.03-2.10] and 1.33 [0.96-1.84]), while other racial minorities had longer LOS (7.0 vs. 5.6 days) and higher hospital charges ($48,984 vs. $41,495) when compared to Whites.

CONCLUSION

The hospitalization rate and burden of PBC in the USA have increased disproportionately among females and Hispanics with higher mortality in Blacks.

Investigation of immune complexes formed by mitochondrial antigens containing a new lipoylated site in sera of primary biliary cholangitis patients

Primary biliary cholangitis (PBC) is characterized by the presence of serum anti-mitochondrial autoantibodies (AMAs). To date, four antigens among the 2-oxo-acid dehydrogenase complex family, which commonly have lipoyl domains as an epitope, have been identified as AMA-corresponding antigens (AMA-antigens). It has recently been reported that AMAs react more strongly with certain chemically modified mimics than with the native lipoyl domains in AMA-antigens. Moreover, high concentrations of circulating immune complexes (ICs) in PBC patients have been reported. However, the existence of ICs formed by AMAs and their antigens has not been reported to date. We hypothesized that AMAs and their antigens formed ICs in PBC sera, and analyzed sera of PBC and four autoimmune diseases (Sjögren's syndrome, systemic lupus erythematosus, systemic scleroderma, and rheumatoid arthritis) using immune complexome analysis, in which ICs are separated from serum and are identified by nano-liquid chromatography-tandem mass spectrometry. To correctly assign MS/MS spectra to peptide sequences, we used a protein-search algorithm that including lipoylation and certain xenobiotic modifications. We found three AMA-antigens, the E2 subunit of the pyruvate dehydrogenase complex (PDC-E2), the E2 subunit of the 2-oxo-glutarate dehydrogenase complex (OGDC-E2) and dihydrolipoamide dehydrogenase binding protein (E3BP), by detecting peptides containing lipoylation and xenobiotic modifications from PBC sera. Although the lipoylated sites of these peptides were different from the well-known sites, abnormal lipoylation and xenobiotic modification may lead to production of AMAs and the formation ICs. Further investigation of the lipoylated sites, xenobiotic modifications, and IC formation will lead to deepen our understanding of PBC pathogenesis.

Clinical Characteristics and Prognosis of Concomitant Primary Biliary Cholangitis and Autoimmune Diseases: A Retrospective Study

OBJECTIVES

Diagnosis and treatment of primary biliary cholangitis (PBC) are often complicated by hepatic and/or extrahepatic manifestations, which in turn affect the natural course and prognosis of PBC. This study evaluated the clinical characteristics and prognosis of PBC co-occurring with intrahepatic and extrahepatic autoimmune disease (AID).

METHODS

Clinical data of patients with PBC who were admitted to the Beijing Ditan Hospital from September 2008 to December 2014 were retrospectively reviewed, assessed for other autoimmune diseases, and analyzed statistically. All patients received ursodeoxycholic acid (UDCA) treatment.

RESULTS

Data from 505 patients were evaluated. Approximately 35.0% of patients had at least one additional AID. AIDs included Sjögren's syndrome (SS; 26.3%), autoimmune hepatitis (AIH; 7.1%), rheumatoid arthritis (RA; 1.4%), hypothyroidism (0.8%), Graves's thyroiditis (0.6%), systemic lupus erythematosus (SLE; 0.4%), and Hashimoto's thyroiditis (0.2%). No differences in response rates of UDCA were found between the PBC group and the PBC-SS group or PBC complicated with AID group (both P > 0.05). White blood cell (WBC, RR = 1.072, 95% CI: 1.016-1.130, P=0.011), platelet counts (PLT, RR = 0.995, 95% CI: 0.992-0.998, P=0.003), and prothrombin time and international normalized ratio (PT/INR, RR = 1.799, 95% CI: 1.010-3.206, P=0.046) were independent prognostic factors in patients with PBC. The overall survival time of patients in PBC-AIH and PBC-SS groups was shorter than that of those with PBC (P < 0.001).

CONCLUSIONS

AIH was the most common in hepatic comorbidity. SS was the most frequent extrahepatic comorbidity. WBC, PLT, and PT/INR were independent prognostic factors in patients with PBC. AID coexisted with PBC impaired patients' survival.

N-acetyl cysteine treatment mitigates biomarkers of oxidative stress in different tissues of bile duct ligated rats

Cholestasis is a multifaceted clinical complication. Obstructive jaundice induced by bile duct ligation (BDL) is known as an animal model to investigate cholestasis and its associated complications. N-acetyl cysteine (NAC) is an antioxidant, radical scavenger, and thiol reductant widely investigated for its cytoprotective properties. The current investigation was designed to evaluate the role of NAC treatment on biomarkers of oxidative stress and organ histopathological alterations in a rat model of cholestasis/cirrhosis. BDL animals were supplemented with NAC (100 and 300 mg/kg, i.p, 42 consecutive days). Biomarkers of oxidative stress in the liver, brain, heart, skeletal muscle, lung, serum, and kidney tissue, as well as organ histopathological changes, were monitored. A significant increase in reactive oxygen species, lipid peroxidation, and protein carbonylation were detected in different tissues of BDL rats. Moreover, tissue antioxidant capacity was hampered, glutathione (GSH) reservoirs were depleted, and oxidized glutathione (GSSG) levels were significantly increased in the BDL group. Significant tissue histopathological alterations were evident in cirrhotic animals. It was found that NAC treatment (100 and 300 mg/kg, i.p) significantly mitigated biomarkers of oxidative stress and alleviated tissue histopathological changes in cirrhotic rats. These data represent NAC as a potential protective agent with therapeutic capability in cirrhosis and its associated complications.HIGHLIGHTSCholestasis is a multifaceted clinical complication that affects different organsOxidative stress plays a pivotal role in cholestasis-associated complicationsTissue antioxidant capacity is hampered in different tissues of cholestatic animalsAntioxidant therapy might play a role in the management of cholestasis-induced organ injuryNAC alleviated biomarkers of oxidative stress in cholestatic animalsNAC significantly improved tissues histopathological alterations in cholestatic rats.

Environmental risk factors and comorbidities of primary biliary cholangitis in Korea: a case-control study

BACKGROUND/AIMS

The risk factors for the development of primary biliary cholangitis (PBC) is unclear. This study aimed to investigate the risk factors associated with PBC in Korea through a questionnaire survey.

METHODS

Consecutively enrolled 103 PBC patients from six referral hospitals and 100 age- and sex-matched community controls participated in this study. A standardized questionnaire survey including demographics, lifestyle, individual and familial medical history and reproductive history was prospectively collected and analyzed.

RESULTS

The PBC patients had a mean age of 58.3 years and a female proportion of 86.4%. The age- and sex-matched controls had a similar educational level and economic status to the PBC patients. Among the lifestyle factors, the multivariable analysis showed smoking including both first-hand and second-hand (odds ratio [OR], 2.03; 95% confidence interval [CI], 1.06 to 3.93), history of autoimmune diseases (OR, 2.46; 95% CI, 1.06 to 6.35), and family history of PBC (OR, 17.76; 95% CI, 1.77 to 2,418.74) were significantly associated with PBC, whereas alcohol intake was negatively associated with PBC. Among reproductive factors, the number of induced abortions was significantly associated with PBC, while the number of full-term deliveries was negatively associated with PBC.

CONCLUSION

A family history of PBC, accompanying autoimmune diseases, and smoking were significantly associated with PBC. More induced abortions and less full-term deliveries were associated with PBC in women. In contrast, mild to moderate alcohol intake was negatively associated with PBC. Further studies are warranted to validate the results of this study and to search for clues about the pathogenesis of PBC.

Primary biliary cholangitis: pathogenic mechanisms

PURPOSE OF REVIEW

Primary biliary cholangitis (PBC) is characterized by autoimmune damage of intrahepatic bile ducts associated with a loss of tolerance to mitochondrial antigens. PBC etiopathogenesis is intriguing because of different perplexing features, namely: a) although mitochondria are present in all cell types and tissues, the damage is mainly restricted to biliary epithelial cells (BECs); b) despite being an autoimmune disorder, it does not respond to immunosuppressive drugs but rather to ursodeoxycholic acid, a bile salt that induces HCO3- rich choleresis; c) the overwhelming female preponderance of the disease remains unexplained. Here we present an etiopathogenic view of PBC which sheds light on these puzzling facts of the disease.

RECENT FINDINGS

PBC develops in patients with genetic predisposition to autoimmunity in whom epigenetic mechanisms silence the Cl-/HCO3- exchanger AE2 in both cholangiocytes and lymphoid cells. Defective AE2 function can produce BECs damage as a result of decreased biliary HCO3- secretion with disruption of the protective alkaline umbrella that normally prevents the penetration of toxic apolar bile salts into cholangiocytes. AE2 dysfunction also causes increased intracellular pH (pHi) in cholangiocytes, leading to the activation of soluble adenylyl cyclase, which sensitizes BECs to bile salt-induced apoptosis. Recently, mitophagy was found to be inhibited by cytosolic alkalization and stimulated by acidification. Accordingly, we propose that AE2 deficiency may disturb mitophagy in BECs, thus, promoting the accumulation of defective mitochondria, oxidative stress and presentation of mitochondrial antigens to the immune cells. As women possess a more acidic endolysosomal milieu than men, mitophagy might be more affected in women in an AE2-defective background. Apart from affecting BECs function, AE2 downregulation in lymphocytes may also contribute to alter immunoregulation facilitating autoreactive T-cell responses.

SUMMARY

PBC can be considered as a disorder of Cl-/HCO3- exchange in individuals with genetic predisposition to autoimmunity.

Functional Role of the Secretin/Secretin Receptor Signaling During Cholestatic Liver Injury

The gastrointestinal peptide, secretin (Sct) is an important homeostatic regulator of pancreatic and liver secretory function. With regard to the liver, discoveries have been made, in the last decades, indicating a key role for the secretin/secretin receptor axis during normal or cholestatic conditions. Since large cholangiocytes are the only cells to express secretin receptor in the liver, research on secretin also expanded our knowledge on biliary epithelia. In this review we examined in detail the role of the secretin/secretin receptor axis, not only on biliary secretion, but also on cholangiocyte proliferation and senescence, as well as in prompting fibrotic processes involving biliary epithelia. Relevant data on human chronic cholestatic liver diseases, such as primary biliary cholangitis or primary sclerosing cholangitis, and obtained in animal models mimicking the diseases or in correlative studies on human are also reported. The aim of this review is to provide an update on the progress regarding the interactions between secretin and the biliary epithelia in normal and pathological conditions, underlining the aspects that suggests modulation of secretin pathway as a possible therapeutic approach for chronic cholestatic human liver disease.

Prevalence of antimitochondrial antibodies in subacute cutaneous lupus erythematosus

BACKGROUND

In approximately 13% of systemic lupus erythematosus (SLE) patients, a hallmark of primary biliary cirrhosis (PBC) can be detected: antimitochondrial M2 antibodies (AMA-M2). It has not been determined if the presence of AMA-M2 in SLE patients results in a higher risk of PBC in comparison to those with AMA but no SLE. Until now, there have been no such analyses among individuals with subacute cutaneous lupus erythematosus (SCLE).

METHODS

To assess the seropositivity rates for AMA-M2 and autoantibodies associated with autoimmune hepatitis in patients with newly diagnosed SCLE and to determine the coexistence and risk of development of autoimmune liver disease in these patients within 1 year of follow-up, data from 33 patients with newly diagnosed SCLE were analyzed.

RESULTS

AMA-M2 was found in 20% of SCLE patients. Patients from the AMA-M2-positive group were characterized by significantly higher levels of cholestatic liver enzymes when compared to those without AMA-M2 (P < 0.05). After introducing therapy with hydroxychloroquine and prednisone, the levels of hepatocellular enzymes increased significantly only in AMA-M2 positive patients (P < 0.05).

CONCLUSIONS

A high prevalence of AMA-M2 was found in patients with SCLE. Patients with SCLE and AMA-M2 had significantly higher values of cholestatic enzymes than patients without AMA. Newly diagnosed patients with SCLE should be screened for the presence of AMA and should be clinically followed up. Avoiding drugs with potential liver toxicity should be recommended in patients with SCLE and AMA.

Risk factors for recurrent autoimmune liver diseases after liver transplantation: A meta-analysis

BACKGROUND

Autoimmune liver disease (ALD) is a chronic liver disease caused by immune dysfunction in the body. However, no causative or curative medical treatment with proven efficacy exists to cure ALDs, and liver transplantation (LT) remains the only effective treatment available. However, the problem of recurrence of ALDs (rALDs) still remains after LT, which seriously affects the survival rate of the patients. Therefore, clinicians need to be aware of the risk factors affecting rALDs after LT. Therefore, this meta-analysis aims to define the risk factors for rALDs, which include the recurrence of primary biliary cirrhosis, primary sclerosing cholangitis and autoimmune hepatitis.

METHODS

A systematic search in Pubmed, Embase, Cochrane library and Web of Science databases was performed from 1980 to 2019. The inclusion criteria were risk factors for developing rALDs after LT. However, case series, case reports, reviews, meta-analysis and studies only including human immunodeficiency virus cases, children, and pregnant patients were excluded.

RESULTS

The electronic database search yielded 1728 results. Sixty-three retrospective cohort studies met the inclusion criteria and 13 were included in the meta-analysis. The final cohort included 5077 patients, and among them, 21.96% developed rALDs. Colectomy before LT, HR 0.59 (95% confidence interval [CI]: 0.37-0.96), cholangiocarcinoma, HR 3.42 (95% CI: 1.88-6.21), multiple episodes of acute cellular rejection, HR 2.07 (95% CI: 1.27-3.37), model for end-stage liver disease score, HR 1.05 (95% CI: 1.02-1.08), use of mycophenolate mofetil, HR 1.46 (95% CI: 1.00-2.12) and the use of cyclosporin A, HR 0.69 (95% CI: 0.49-0.97) were associated with the risk of rprimary sclerosing cholangitis. In addition, the use of tacrolimus, HR 1.73 (95% CI: 1.00-2.99) and cyclosporin A, HR 0.59 (95% CI: 0.39-0.88) were associated with the risk of rALD.

CONCLUSIONS

Multiple risk factors for rALDs were identified, such as colectomy before LT, cholangiocacinoma, multiple episodes of acute cellular rejection, model for end-stage liver disease score, and especially the use of mycophenolate mofetil, cyclosporin A and tacrolimus.

Morphometric changes and imaging findings of diffuse liver disease in relation to intrahepatic hemodynamics

Diffuse hepatic diseases have a variety of etiologies, with each showing characteristic morphometric changes. These changes are closely related to micro- and macro-level intrahepatic hemodynamics, in addition to the specific underlying pathophysiology. Short-term disorders in intrahepatic hemodynamics caused by each pathophysiological condition are compensated for by the balance of blood perfusion systems using potential trans-sinusoidal, transversal, and transplexal routes of communication (micro-hemodynamics), while long-term alterations to the intrahepatic hemodynamics result in an increase in total hepatic vascular resistance. Blood flow disorders induced by this increased vascular resistance elicit hepatic cellular necrosis and fibrosis. These changes should be uniformly widespread throughout the whole liver. However, morphometric changes do not occur uniformly, with shrinkage or enlargement not occurring homogeneously. Against this background, several macro-intrahepatic hemodynamic effects arise, such as asymmetrical and complicating morphometric structures of the liver, intricate anatomy of portal venous flow and hepatic venous drainage, and zonal differentiation between central and peripheral zones. These hemodynamic factors and pathophysiological changes are related to characteristic morphometric changes in a complicated manner, based on the combination of selective atrophy and compensatory hypertrophy (atrophy-hypertrophy complex). These changes can be clearly depicted on CT and MR imaging.

Cholestatic liver injury induced by food additives, dietary supplements and parenteral nutrition

Cholestasis refers to the accumulation of toxic levels of bile acids in the liver due to defective bile secretion. This pathological situation can be triggered by drugs, but also by ingredients contained in food, food supplements and parenteral nutrition. This paper provides an overview of the current knowledge on cholestatic injury associated with such ingredients, with particular emphasis on the underlying mechanisms of toxicity.

Outcomes of Liver Transplant Candidates with Primary Biliary Cholangitis: The Data from the Scientific Registry of Transplant Recipients

BACKGROUND

Primary biliary cholangitis (PBC) is progressive and can cause end-stage liver disease necessitating a liver transplant (LT). PBC patients may be disadvantaged on LT waitlist due to MELD-based priority listing or other factors.

AIM

The aim was to assess waitlist duration, waitlist mortality, and post-LT outcomes of PBC patients.

METHODS

The Scientific Registry of Transplant Recipients data for 1994-2016 was utilized. Adult patients with PBC without hepatocellular carcinoma (HCC) were selected. Their clinico-demographic parameters and waitlist and post-transplant outcomes were compared to those of patients with hepatitis C (HCV) without HCC.

RESULTS

Out of 223,391 listings for LT in 1994-2016, 8133 (3.6%) was for PBC without HCC. Mean age was 55.5 years, 76.9% white, 86.2% female, mean MELD score 21, 6.6% retransplants. There were 52,017 patients with hepatitis C included for comparison. The mean waitlist mortality was 17.9% for PBC and 17.6% for HCV (p > 0.05). The average transplantation rate was 57.7% for PBC and 53.3% for HCV (p < 0.0001), while waitlist dropout (death or removal due to deterioration) rate was 25.0% for PBC and 25.4% for HCV (p > 0.05). There was no significant difference in median waiting duration till transplantation between PBC patients and HCV after 2002 (103 vs. 95 days, p > 0.05). Post-LT mortality and graft loss rates were significantly lower in PBC than in HCV patients (all p < 0.02).

CONCLUSIONS

Despite no evidence of impaired waitlist outcomes and favorable post-transplant survival in patients with PBC, there is still a high waitlist dropout rate suggesting the presence of an unmet need for effective treatment.

Emerging therapies for PBC

Primary biliary cholangitis is an uncommon cholestatic liver disease predominantly affecting middle-aged women. Left untreated, there is a high risk of progression to end-stage liver disease. Few treatment options exist. To date, ursodeoxycholic acid (UDCA) and obeticholic acid (OCA) are the only medical therapies approved for use, other than symptomatic treatments and liver transplantation, the latter of which is reserved for those developing complications of cirrhosis or with intractable pruritus. UDCA improves outcomes, but many patients do not adequately respond. OCA therapy may improve response, but long-term data are limited. New therapies are desperately needed, but evaluation has been limited by the fact that the disease is heterogeneous, hard end points take years to develop, and there are different criteria in use for determining therapeutic response based on surrogate biomarkers. Fibrates appear to be the most promising new therapy and have beneficially affected surrogate end points and are beginning to show improvement in clinical end points.

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.

Biochemical and plasma lipid responses to pemafibrate in patients with primary biliary cholangitis

AIM

Fibrate addition to ursodeoxycholic acid (UDCA) therapy has been shown to improve both liver biochemistry and long-term prognosis in primary biliary cholangitis (PBC) patients showing an incomplete biochemical response to UDCA alone. We herein describe the clinical outcome of seven cases of PBC that received the new selective peroxisome proliferator-activated receptor α modulator, pemafibrate, in combination with UDCA therapy to investigate the biochemical and plasma lipid responses to the drug.

METHODS

Of 124 initially enrolled PBC patients, 12 treated with UDCA alone and seven receiving UDCA plus bezafibrate showed alkaline phosphatase (ALP) levels above the upper limit of normal (330 U/L). Ultimately, seven patients with PBC and dyslipidemia who had agreed to biweekly visits at our hospital for UDCA plus pemafibrate combination therapy were retrospectively analyzed.

RESULTS

In the four cases that switched from bezafibrate to pemafibrate, ALP became significantly decreased (0.031) and γ-glutamyltransferase tended to decrease (0.063) over the 3 months following pemafibrate addition. Two patients showed a greater than 50% reduction in ALP. No remarkable differences were observed for plasma lipid levels, alanine aminotransferase, aspartate aminotransferase, or the liver fibrosis marker Mac-2 binding protein glycosylation isomer between these time points. No adverse drug reactions were recorded.

CONCLUSIONS

Pemafibrate might be another option for PBC patients with an incomplete response to UDCA therapy.

The Pharmacology of Bile Acids and Their Receptors

This review provides a historical perspective of bile acids and their receptors as therapeutic targets. Bile acids are atypical steroids generated by the liver from cholesterol and have been used for almost half a century for treating liver and biliary disorders. Since the early 1970s of the last century, chenodeoxycholic acid (CDCA), a primary bile acid, and ursodeoxycholic acid (UDCA), a secondary bile acid and the 7βepimer of CDCA, have been shown effective in promoting the dissolution of cholesterol gallstones. However, lack of activity and side effects associated with the use of CDCA, along with the advent of laparoscopic cholecystectomy, have greatly reduced the clinical relevance of this application. At the turn of the century, however, the discovery that bile acids activate specific receptors, along with the discovery that those receptors are placed at the interface of the host and intestinal microbiota regulating physiologically relevant enterohepatic and entero-pancreatic axes, has led to a "bile acid renaissance." Similarly to other steroids, bile acids bind and activate both cell surface and nuclear receptors, including the bile acid sensor farnesoid X receptor (FXR) and a G-protein-coupled bile acid receptor, known as GPBAR1 (TGR5). Both receptors have been proved druggable, and several highly potent, selective, and nonselective ligands for the two receptors have been discovered in the last two decades. Currently, in addition to obeticholic acid, a semisynthetic derivative of CDCA and the first in class of FXR ligands approved for clinical use, either selective or dual FXR and GPBAR1 ligands, have been developed, and some of them are undergoing pre-approval trials. The effects of FXR and GPBAR1 ligands in different therapeutic area are reviewed.

Effectiveness of bezafibrate and ursodeoxycholic acid in patients with primary biliary cholangitis: a meta-analysis of randomized controlled trials

Background

Ursodeoxycholic acid (UDCA) and obeticholic acid are currently approved treatments for primary biliary cholangitis (PBC). Since some patients do not respond adequately to UDCA, other therapies, such as bezafibrate, have been developed. In this meta-analysis we evaluated the efficacy and safety of using both UDCA and bezafibrate in patients with an inadequate response to UDCA.

Methods

We evaluated all randomized controlled trials comparing the combination of UDCA and bezafibrate with UDCA monotherapy. Standardized mean difference (SMD) was used to assess the treatment effect of combination therapy compared with UDCA alone.

Results

Ten trials with a total of 369 patients were analyzed. UDCA and bezafibrate combination therapy was more effective than UDCA monotherapy in improving alanine aminotransferase (SMD -2.04, 95% confidence interval [CI] -3.30 to -0.79), alkaline phosphatase at both less than 12 months (SMD -3.63, 95%CI -6.43 to -0.84) and more than 12 months (SMD -2.33, 95%CI -4.03 to -0.63), gamma-glutamyltransferase (SMD -1.29, 95%CI -2.67 to 0.08), triglyceride (SMD -0.80, 95%CI -1.41 to -0.19), immunoglobulin M (SMD -1.48, 95%CI -2.39 to -0.56), and cholesterol (SMD -4.61, 95%CI -7.34 to -1.89). There was no difference between the 2 groups in bilirubin, aspartate aminotransferase or albumin. None of the adverse effects differed statistically between the 2 groups.

Conclusion

UDCA and bezafibrate combined treatment is superior to UDCA alone in UDCA non-responders with regard to decreasing liver biochemistry markers, without any significant increase in side effects in patients with PBC.

The Potential Effects of Diabetes Mellitus on Liver Fibrosis in Patients with Primary Biliary Cholangitis

Background

The impact of diabetes mellitus (DM) on the natural progression of primary biliary cholangitis (PBC) has not yet been determined. The objective of this study was to determine whether DM is associated with increased liver damage in PBC.

Material/Methods

There were 168 treatment-naïve PBC patients, including 37 patients with DM, enrolled in this study between 2012 and 2018. Patient demographics, clinical features, and biochemical and histopathological parameters were collected. Disease severity was assessed by pathological data, Child Pugh grade, and noninvasive indicators. Relevant risks for PBC-related cirrhosis were assessed by univariate and multivariate analyses.

Results

The noninvasive scores predicting fibrosis were all significantly higher in PBC-DM versus PBC-only patients (fibrosis-4 score: 4.08 versus 3.21, P=0.029; aminotransferase-to-platelet ratio index: 1.46 versus 1.09, P=0.036; red blood cell distribution width to platelet ratio: 0.12 versus 0.08, P=0.016; Mayo Risk Score: 1.52 versus 0.19, P=0.011; the Newcastle model: 2.85 versus 2.07, P=0.009; albumin-bilirubin score: −1.92 versus −2.10, P=0.023). Cirrhosis occurred at a higher rate (62.2% versus 42.0%, P=0.030) in PBC-DM patients, but Child Pugh grade and pathological differences could not be accurately determined. A multivariate analysis revealed DM increased the risk of PBC-related cirrhosis, with a resulting adjusted odds ratio of 2.351 (95% confidence interval, 1.022–5.409).

Conclusions

The results of this retrospective, single-center study suggest that DM is associated with more severe liver fibrosis in PBC. Consequently, improved management of DM might alter the prognosis of PBC patients.

New treatments/targets for primary biliary cholangitis

Primary biliary cholangitis (PBC) is an autoimmune, cholestatic, chronic liver disease that ultimately progresses towards cirrhosis and liver failure if untreated. While ursodeoxycholic acid has been established as standard of care for PBC in the last few decades, significant advances in second-line treatment options have recently been made and new therapeutic developments are currently under evaluation. The purpose of this article is to provide the clinician with an overview of the current treatment options and future opportunities for patients with PBC.

Promoter hypermethylation of the AE2/SLC4A2 gene in PBC

Background & Aims

Patients with primary biliary cholangitis (PBC) exhibit reduced AE2/SLC4A2 gene expression in the liver and peripheral blood mononuclear cells (PBMCs). AE2 encodes a Cl^–/HCO₃^– exchanger involved in biliary bicarbonate secretion and intracellular pH regulation. Reduced AE2 expression in PBC may be pathogenic, as Ae2-knockout mice reproduce characteristic PBC features. Herein, we aimed to identify CpG-methylation abnormalities in AE2 promoter regions that might contribute to the reduced gene transcription in PBC livers and PBMCs.

Methods

CpG-cytosine methylation rates were interrogated at 1-base pair resolution in upstream and alternate AE2 promoter regions through pyrosequencing of bisulphite-modified genomic DNA from liver specimens and PBMCs. AE2a and alternative AE2b1 and AE2b2 mRNA levels were measured by real-time PCR. Human lymphoblastoid-T2 cells were treated with 5-aza-2´-deoxycytidine for demethylation assays.

Results

AE2 promoters were found to be hypermethylated in PBC livers compared to normal and diseased liver specimens. Receiver operating characteristic (ROC) curve analysis showed that minimal CpG-hypermethylation clusters of 3 AE2a-CpG sites and 4 alternate-AE2b2-CpG sites specifically differentiated PBC from normal and diseased controls, with mean methylation rates inversely correlating with respective transcript levels. Additionally, in PBMCs a minimal cluster of 3 hypermethylated AE2a-CpG sites distinguished PBC from controls, and mean methylation rates correlated negatively with AE2a mRNA levels in these immune cells. Alternate AE2b2/AE2b1 promoters in PBMCs were constitutively hypermethylated, in line with absent alternative mRNA expression in diseased and healthy PBMCs. Demethylation assays treating lymphoblastoid-T2 cells with 5-aza-2´-deoxycytidine triggered AE2b2/AE2b1 expression and upregulated AE2a-promoter expression.

Conclusions

Disease-specific hypermethylation of AE2 promoter regions and subsequent downregulation of AE2-gene expression in the liver and PBMCs of patients with PBC might be critically involved in the pathogenesis of this complex disease.

Lay summary

Primary biliary cholangitis (PBC) is a chronic immune-associated cholestatic liver disease with unclear complex/multifactorial etiopathogenesis affecting mostly middle-aged women. Patients with PBC exhibit reduced expression of the AE2/SLC4A2 gene. Herein, we found that AE2 promoter regions are hypermethylated in the liver and peripheral blood mononuclear cells of patients with PBC. This increased methylation is associated with downregulated AE2-gene expression, which might contribute to the pathogenesis of PBC. Therefore, novel epigenetic targets may improve treatment in patients with PBC who respond poorly to current pharmacological therapies.

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Patients with PBC have higher AE2 CpG methylation in upstream AE2a and/or AE2b2/AE2b1 promoter regions in liver and PBMCs.

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Combined methylation rates of 2 minimal CpG-clusters in the liver and 1 minimal CpG-cluster in PBMCs specifically distinguished PBC from normal and diseased controls.

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Methylation rates of AE2 promoter regions inversely correlated with levels of respective AE2 mRNAs in liver and PBMCs.

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Alternate AE2b2/AE2b1 promoter regions were found to be densely methylated in both normal and diseased PBMC samples.

CD4+ T cells from patients with primary biliary cholangitis show T cell activation and differentially expressed T-cell receptor repertoires

AIM

Primary biliary cholangitis (PBC) is an autoimmune liver disease with unknown pathogenesis. In PBC, activation of T-cell receptor (TCR) signaling is associated with inflammatory cytokine production through N-Ras upregulation. Although the CD4⁺ T cell TCR repertoire could be associated with PBC pathogenesis, it has not been evaluated. Thus, we analyzed the PBC-CD4⁺ T cell TCR repertoire using next generation sequencing (NGS).

METHODS

Four PBC patients (one treatment-naïve and three receiving ursodeoxycholic acid) and three healthy individuals were enrolled. NRAS expression in CD4⁺ T cells was assessed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). N-Ras dynamics in CD4⁺ T cells were assessed by qRT-PCR and GTP-N-Ras activation assay. The TCR α- (TRA) and β-chain (TRB) repertoires on CD4⁺ T cells were analyzed by NGS and profiled using hierarchical analysis. Motif analysis was undertaken to elucidate the structure of PBC-specific TCRs.

RESULTS

NRAS was upregulated in PBC relative to control CD4⁺ T cells (P < 0.05), and N-Ras enhanced T cell activation in CD4⁺ T cells. Among 2668 TRAs and 841 TRBs, 20 and 11, respectively, were differentially expressed in PBC compared to that in controls (P < 0.05, fold-change >2). Among them, TRAV29/J22, TRBV6-5/J2-6, and TRBV10-1/J2-1 were expressed in PBC but the expression was negligible in the controls, with more mature and longer forms observed in PBC-CD4⁺ T cells.

CONCLUSIONS

N-Ras was upregulated in PBC-CD4⁺ T cells, and it enhanced TCR activation, indicating that PBC-CD4⁺ T cells were activated by N-Ras upregulation with differentially expressed TCR repertoires on their surfaces.

Primary biliary cholangitis patients exhibit MRI changes in structure and function of interoceptive brain regions

Background

Many patients with primary biliary cholangitis (PBC) experience non-hepatic symptoms that are possibly linked to altered interoception, the sense of the body’s internal state. We used magnetic resonance imaging (MRI) to determine if PBC patients exhibit structural and functional changes of the thalamus and insula, brain regions that process signals related to interoception.

Methods

Fifteen PBC patients with mild disease and 17 controls underwent 3 Tesla T₁-weighted MRI, resting-state functional MRI, and quantitative susceptibility mapping (QSM), to measure thalamic and insular volume, neuronal activity and iron deposition, respectively. Group differences were assessed using analysis of covariance, and stepwise linear regression was used to determine the predictive power of clinical indicators of disease.

Results

PBC patients exhibited reduced thalamic volume (p < 0.01), and ursodeoxycholic acid (UDCA) non-responders exhibited lower left thalamus activity (p = 0.05). PBC patients also exhibited reduced anterior insula activity (p = 0.012), and liver stiffness positively correlated with MRI indicators of anterior insula iron deposition (p < 0.02).

Conclusions

PBC affects structure and function of brain regions critically important to interoception. Moreover, these brain changes occur in patients with early, milder disease and thus may potentially be reversible.

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.

Factors Associated With Recurrence of Primary Biliary Cholangitis After Liver Transplantation and Effects on Graft and Patient Survival

BACKGROUND & AIMS

Primary biliary cholangitis (PBC) frequently recurs after liver transplantation. We evaluated risk factors associated with recurrence of PBC and its effects on patient and graft survival in a multicenter, international cohort (the Global PBC Study Group).

METHODS

We collected demographic and clinical data from 785 patients (89% female) with PBC who underwent liver transplantation (mean age, 54 ± 9 years) from February 1983 through June 2016, among 13 centers in North America and Europe. Results from biochemical tests performed within 12 months of liver transplantation were analyzed to determine whether markers of cholestasis could identify patients with recurrence of PBC (based on histologic analysis). Patients were followed for a median 6.9 years (interquartile range, 6.1-7.9 years).

RESULTS

PBC recurred in 22% of patients after 5 years and 36% after 10 years. Age at diagnosis <50 years (hazard ratio [HR], 1.79; 95% CI, 1.36-2.36; P < .001), age at liver transplantation <60 years (HR, 1.39; 95% CI, 1.02-1.90; P = .04), use of tacrolimus (HR, 2.31; 95% CI, 1.72-3.10; P < .001), and biochemical markers of severe cholestasis (bilirubin ≥100 μmol or alkaline phosphatase >3-fold the upper limit of normal) at 6 months after liver transplantation (HR, 1.79; 95% CI, 1.16-2.76; P = .008) were associated with higher risk of PBC recurrence, whereas use of cyclosporine reduced risk of PBC recurrence (HR, 0.62; 95% CI, 0.46-0.82; P = .001). In multivariable Cox regression with time-dependent covariate, recurrence of PBC significantly associated with graft loss (HR, 2.01; 95% CI, 1.16-3.51; P = .01) and death (HR, 1.72; 95% CI, 1.11-2.65; P = .02).

CONCLUSIONS

Younger age at the time of diagnosis with PBC or at liver transplantation, tacrolimus use, and biochemical markers of cholestasis after liver transplantation are associated with PBC recurrence. PBC recurrence reduces odds of graft and patient survival. Strategies are needed to prevent PBC recurrence or reduce its negative effects.

A facile synthesis of ursodeoxycholic acid and obeticholic acid from cholic acid

A novel synthetic route of producing ursodeoxycholic acid (UDCA) and obeticholic acid (OCA) was developed through multiple reactions from cheap and readily-available cholic acid. The reaction conditions of the key elimination reaction of mesylate ester group were also investigated and optimized, including solvent, base and reaction temperature. In the straightforward synthetic route for preparation of UDCA and OCA, most of the reaction steps have high conversions with average yields of 94% and 92%, and overall yield up to 65% (7 steps) and 36% (11 steps) from cholic acid, respectively. This promising route offers economical and efficient strategies for potential large-scale production of UDCA and OCA.

Increased red cell width distribution to lymphocyte ratio is a predictor of histologic severity in primary biliary cholangitis

Primary biliary cholangitis (PBC) is a chronic disease that is increasingly being recognized in recent years. In this study, we sought to identify noninvasive markers of the severity of cirrhosis in patients with PBC based on routinely investigated laboratory parameters.Ninety-four patients with histologically-confirmed PBC based on liver biopsy performed between January 2013 and December 2017 at the First Hospital of Jilin University were divided into 2 groups: early-stage cirrhosis (fibrosis stage F1 and F2; n = 74) and advanced-stage cirrhosis (fibrosis stage F3 and F4; n = 20).Patients with advanced-stage had significantly higher red blood cell distribution width (RDW) (15.2 vs 13.7; P = .003) and significantly lower platelet (163.35 vs 202.73; P = .032) and lymphocyte counts (1.47 vs 1.79; P = .018) as compared with patients with early-stage cirrhosis. Advanced-stage cirrhosis was associated with significantly higher RDW to platelet ratio (RPR), RDW to lymphocyte ratio (RLR), aspartate aminotransferase to platelet ratio index (APRI), and fibrosis index based on the 4 factors (FIB-4) as compared with early-stage cirrhosis. RLR showed the highest area under receiver operating characteristic curve (AUROC) (0.744). The sensitivity and specificity of RLR were 65% and 78.3%, respectively. RLR had higher AUROC than the other 3 noninvasive markers.The noninvasive markers RPR, RLR, APRI, and FIB-4 showed good diagnostic accuracy for advanced-stage cirrhosis. These markers are easily acquired by routine laboratory tests and are reproducible predictors of the severity of PBC. RLR is a novel marker that may serve as a valuable supplement to APRI and FIB-4 for predicting the severity of cirrhosis.

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.

Risk stratification and treatment of primary biliary cholangitis

Primary biliary cholangitis is a chronic liver disorder characterized by progressive cholestasis that may evolve to liver cirrhosis. While ursodeoxycholic acid is the treatment of choice, around 30% of patients do not respond to this therapy. These patients have a poorer prognosis, hence should be identified early in order to be offered therapy options. Along these lines, improved understanding of the condition's pathophysiology has allowed the development of newer drugs, including obeticholic acid and fibrates. This review offers a perspective on risk stratification and treatment for these patients, from ursodeoxycholic acid to second-line treatments.

Myeloid Cells and Chronic Liver Disease: a Comprehensive Review

Myeloid cells play a major role in the sensitization to liver injury, particularly in chronic inflammatory liver diseases with a biliary or hepatocellular origin, and the interplay between myeloid cells and the liver may explain the increased incidence of hepatic osteodystrophy. The myeloid cell-liver axis involves several mature myeloid cells as well as immature or progenitor cells with the complexity of the liver immune microenvironment aggravating the mist of cell differentiation. The unique positioning of the liver at the junction of the peripheral and portal circulation systems underlines the interaction of myeloid cells and hepatic cells and leads to immune tolerance breakdown. We herein discuss the scenarios of different chronic liver diseases closely modulated by myeloid cells and illustrate the numerous potential targets, the understanding of which will ultimately steer the development of solid immunotherapeutic regimens. Ultimately, we are convinced that an adequate modulation of the liver microenvironment to modify the functional and quantitative characteristics of myeloid cells will be a successful approach to treating chronic liver diseases of different etiologies.