Autoimmune Liver Diseases and Rheumatoid Arthritis-Is There an Etiopathogenic Link?

Rheumatoid arthritis (RA) is a systemic immune-mediated disease that, in addition to the articular involvement, can have extra-articular manifestations. Even though liver damage in RA is not very common, associated autoimmune liver diseases (AILDs) may occur. The most common AILD associated with RA is primary biliary cirrhosis (PBC), followed by autoimmune hepatitis (AIH) and primary sclerosing cholangitis (PSC). There are common underlying mechanisms that play a role in the emergence of autoimmunity and inflammation in both rheumatic and autoimmune liver diseases. Genetic studies have revealed the existence of several common disease-associated genes shared between RA and AILDs, and infectious triggers, particularly those associated with recurrent or complicated urinary tract infections, are also speculated to be potential triggers for these conditions. Moreover, these diseases share common serologic patterns characterized by the presence of specific autoantibodies and hyper-gammaglobulinemia. In this study, we focus on reviewing the association between RA and AILDs regarding the prevalence and possible etiopathogenic link.

Patented Farnesoid X receptor modulators: a review (2019 - present)

INTRODUCTION

The Farnesoid X receptor (FXR) is a key transcription factor that is involved in the bile acid signaling network. The modulation of the FXR activity influences glucose and lipid homeostasis, reduces obesity and insulin resistance, as well as it regulates the pathogenesis of inflammatory and metabolic disorders. FXR ligands have therefore emerged in drug discovery as promising therapeutic agents for the prevention and treatment of gastrointestinal and liver diseases, including cancer.

AREAS COVERED

Recent advances in the field of FXR modulators are reviewed, with a particular attention on patent applications filed in the past 5 years related to both the discovery and development of FXR targeting drugs.

EXPERT OPINION

FXR agonists have proven their efficacy and safety in humans and have shown a significant potential as clinical agents to treat metabolic and inflammatory associated conditions. However, several challenges, including adverse events such as pruritus, remain to be solved. Current studies aim to gain insights into the pathophysiological mechanisms by which FXR regulates metabolism and inflammation in terms of tissue/organ/isoform-specificity, post-translational modifications and coregulatory proteins, on the route of novel, improved FXR modulators.

Unprecedented complexity of six coexisting autoimmune diseases: A case report

INTRODUCTION

Autoimmune disorders often exhibit interconnectedness, although encountering multiple autoimmune conditions in a single patient is uncommon. Multiple autoimmune syndrome is characterized by the presence of at least three distinct autoimmune diseases in an individual. This report outlines the case of a middle-aged woman diagnosed with autoimmune thyroiditis, Sjögren's syndrome, scleroderma, autoimmune hepatitis, primary biliary cirrhosis, and antisynthetase syndrome. Additionally, it includes a literature review encompassing multiple autoimmune syndromes involving five or more autoimmune diseases.

OBSERVATION

A 57-year-old woman, with no previous medical history, presented with fever, extensive muscle weakness, progressive exertional dyspnea, inflammatory polyarthralgia, dysphagia, and dry mouth. Clinical examination revealed muscular deficit in the scapular and pelvic girdles, distal muscular deficit, synovitis in the wrists, and features indicative of "mechanic's hand". Laboratory examinations showed cytolysis, cholestasis, elevated muscle enzymes, hypergammaglobulinemia and elevated thyroid stimulating hormone. Immunoassays showed positive results for antinuclear antibodies, anti-histidyl-t-RNA synthetase, anti-Sjögren's-syndrome-related antigen A, anti-ribonucleic-acid-polymerase-III-RP155, anti-fibrillarin, anti-mitochondrial, anti-liver/kidney microsomal type 1, anti-glycoprotein 210, and anti-thyroid peroxidase antibodies. Further investigations led to the diagnosis of a multiple autoimmune syndrome involving autoimmune thyroiditis, Sjögren's syndrome, scleroderma, autoimmune hepatitis, primary biliary cirrhosis, and antisynthetase syndrome. The patient received treatment with intravenous immunoglobulins, corticosteroids, azathioprine, and ursodeoxycholic acid, which resulted in favorable clinical and biological outcomes.

CONCLUSION

This patient presented with six concurrent distinct autoimmune disorders, categorizing this case as a type two multiple autoimmune syndrome. The identification of antisynthetase syndrome notably distinguishes this case.

Add-on immunosuppressive therapy may benefit selected patients with primary biliary cholangitis and autoimmune phenomena

Background

Mildly elevated levels of transaminase and/or immunoglobulin G (IgG) are common in patients with primary biliary cholangitis (PBC). It is still unclear whether adding immunosuppressive therapy to ursodeoxycholic acid (UDCA) benefits those patients who are not fulfilling the diagnostic criteria of PBC with autoimmune hepatitis (AIH) features.

Objectives

To assess the efficacy of adding immunosuppressive therapy to UDCA for patients with PBC and autoimmune phenomena but not fulfilling the diagnostic criteria of PBC with AIH features.

Design

This is a retrospective-prospective cohort study in a tertiary medical center.

Methods

Patients with PBC and autoimmune phenomena were defined by the elevation of IgG and/or transaminase but did not fulfill the diagnostic criteria of PBC with AIH features. We grouped these patients based on with and without add-on immunosuppressive therapy and balanced their baseline characteristics using inverse probability treatment weighting (IPTW).

Results

A total of 652 patients with PBC and autoimmune phenomena were included, with a median follow-up of 4.08 years. After IPTW, the pseudo sample size in the add-on therapy and monotherapy groups was 558 and 655, respectively. After 1 year of observation, patients in the add-on therapy group had a higher biochemical response rate (normalization of transaminase and IgG levels) (49% versus 17%, p < 0.001). Furthermore, add-on therapy improved the transplant-free survival in the subgroup of patients with PBC and transaminase ⩾3 × upper limit of normal (ULN) or IgG ⩾1.3 × ULN (p = 0.033).

Conclusion

Add-on immunosuppressive therapy may improve the normalization rates of transaminase and IgG levels in all patients with PBC and mildly elevated transaminase and IgG levels and the long-term outcomes in the subgroup of the patients with transaminase ⩾3 × ULN or IgG ⩾1.3 × ULN.

Primary biliary cirrhosis and psoriasis: a two-sample Mendelian randomization study

Background

Primary biliary cirrhosis (PBC) and psoriasis are frequently observed to co-occur in clinical settings. However, the causal associations and underlying mechanisms between PBC and psoriasis remain poorly defined.

Methods

In this study, we conducted bidirectional MR analysis to explore the causal relationship between PBC and psoriasis using four MR methods: inverse-variance weighted, MR-Egger regression, weighted median, and weighted mode. Sensitivity analyses were carried out, employing different models and testing methods for comparison to assess the influence of heterogeneity and pleiotropy on our findings and to confirm the robustness of these results.

Results

A causal relationship between the risk of PBC and psoriasis was identified, as confirmed by IVW analysis (OR: 1.081, 95%CI: 1.028~1.137, P<0.05). The other three MR methods also produced similar results. However, psoriasis did not have a causal effect on PBC risk (OR: 1.022, 95%CI: 0.935~1.118, P>0.05). The intercept of MR-Egger regression was 0.0013 (P>0.05), indicating that genetic pleiotropy did not influence the results. Additionally, the leave-one-out analysis demonstrated the robustness of our MR findings.

Conclusion

This study reveals a causal relationship between PBC and psoriasis, with PBC increasing the risk of psoriasis, but not the reverse. This potential causal relationship offers a new perspective on the etiology of PBC.

Primary biliary cirrhosis and osteoporosis: a bidirectional two-sample Mendelian randomization study

Background

Observational studies have identified a heightened risk of osteoporosis and fractures in patients with primary biliary cholangitis (PBC). However, conclusive evidence establishing a causal relationship between the two, and a clear mechanism explaining this association, remains elusive.

Methods

We conducted a bidirectional two-sample Mendelian randomization (MR) analysis to investigate the causal relationship between PBC and osteoporosis. This analysis utilized five MR methods: inverse-variance weighted (IVW), MR-Egger, weighted median, weighted mode, and simple mode. Sensitivity analyses were performed, employing various models and testing methods, to assess the impact of heterogeneity and pleiotropy on the results and to confirm their robustness.

Results

A causal relationship between PBC and osteoporosis risk was established through IVW analysis (OR: 1.049, 95%CI: 1.017-1.082, P=0.002). Three other MR analyses corroborated these findings. Conversely, osteoporosis was not found to causally affect PBC risk, as evidenced by IVW analysis (OR: 0.941, 95%CI: 0.783-1.129, P=0.511). Across all MR analyses, no heterogeneity or horizontal pleiotropy was detected among the instrumental variables (IVs). Furthermore, the leave-one-out analysis indicated that no single SNP disproportionately influenced the results, affirming the reliability of the bidirectional MR findings.

Conclusion

This study establishes a positive causal relationship between PBC and the risk of osteoporosis, while no definitive causal link was found from osteoporosis to PBC. These findings offer new insights and guidance for managing bone health in PBC patients.

Antimitochondrial antibody-negative primary biliary cirrhosis with secondary Sjogren syndrome: a case report

Introduction and importance

Primary biliary cholangitis (PBC) is a rare immune-mediated liver disease characterized by the destruction of intrahepatic bile ducts and a positive antimitochondrial antibody (AMA), which is considered a serological hallmark for the diagnosis. Rarely, AMA can be absent/nondetectable in a few cases and is referred to as 'AMA-negative'.

Case presentation

The authors present such an uncommon case of AMA-negative PBC in a 39-year-female with Sjogren's syndrome who presented with fatigue, pruritus, and dry eyes.

Clinical discussion

Previously published studies state that approximately only about 5% of patients with PBC are 'AMA-negative'. For patients negative for AMA, the diagnosis has to be based on typical pathological features of this disease. Once a diagnosis of PBC is established, regardless of whether it is positive or negative for AMAs, ursodeoxycholic acid is a widely accepted treatment.

Conclusion

The presence/absence of AMAs is associated with similar clinical, biochemical, and histopathological characteristics in PBC. The identification of AMAs alone should not impact the diagnosis or treatment of PBC.

The causality between gut microbiome and liver cirrhosis: a bi-directional two-sample Mendelian randomization analysis

Background and aim

Previous studies have reported an association between gut microbiota and cirrhosis. However, the causality between intestinal flora and liver cirrhosis still remains unclear. In this study, bi-directional Mendelian randomization (MR) analysis was used to ascertain the potential causal effect between gut microbes and cirrhosis.

Methods

Large-scale Genome Wide Association Study (GWAS) data of cirrhosis and gut microbes were obtained from FinnGen, Mibiogen consortium, and a GWAS meta-analysis of Alcoholic cirrhosis (ALC). Two-sample MR was performed to determine the causal relationship between gut microbiota and cirrhosis. Furthermore, a bi-directional MR analysis was employed to examine the direction of the causal relations.

Result

In MR analysis, we found that 21 gut microbiotas were potentially associated with cirrhosis. In reverse MR analysis, 11 gut microbiotas displayed potentially associations between genetic liability in the gut microbiome and cirrhosis. We found that the family Lachnospiraceae (OR: 1.59, 95% CI:1.10-2.29) might be harmful in cirrhotic conditions (ICD-10: K74). Furthermore, the genus Erysipelatoclostridium might be a protective factor for cirrhosis (OR:0.55, 95% CI:0.34-0.88) and PBC (OR:0.68, 95% CI:0.52-0.89). Combining the results from the MR analysis and reverse MR analysis, we firstly identified the Genus Butyricicoccus had a bi-directional causal effect on PBC (Forward: OR: 0.37, 95% CI:0.15-0.93; Reverse: OR: 1.03, 95% CI:1.00-1.05).

Conclusion

We found a new potential causal effect between cirrhosis and intestinal flora and provided new insights into the role of gut microbiota in the pathological progression of liver cirrhosis.

Spleen Thickness Plus Platelets Can Effectively and Safely Screen for High-Risk Varices in Cirrhosis Patients

Currently, most primary hospitals cannot routinely perform liver stiffness measurements (LSMs) and spleen stiffness measurements (SSMs), which are recommended by guidelines to exclude high-risk varices (HRVs). We tried to find more convenient indicators for HRV screening. We enrolled 213 cirrhosis patients as the training cohort (TC) and 65 primary biliary cirrhosis patients as the validation cohort (VC). We included indicators such as SSM by two-dimensional shear wave elastography, LSM by transient elastography, and other imaging and laboratory tests. Variable analysis revealed SSM, platelets (PLT), and spleen thickness (ST) as independent risk indicators for HRV. In TC, ST+PLT (ST < 42.2 mm and PLT > 113.5 × 109/L) could avoid 35.7% of the esophagogastroduodenoscopies (EGDs), with a 2.4% missed HRV rate. Although the proportion of EGDs spared by ST+PLT was less than SSM+PLT (SSM < 29.89 kPa + PLT > 113.5 × 109/L) (35.7% vs. 44.1%), it was higher than that of the Baveno VI criteria (B6) (35.7% vs. 28.2%). We did not validate SSM+PLT in VC considering our aims. ST+PLT safely spared 24.6% of EGDs in VC, identical to B6. Conclusions: The ability of ST+PLT to exclude HRVs was superior to B6 but slightly inferior to SSM+PLT. When SSM cannot be routinely performed, ST+PLT provides an extra option for patients to exclude HRVs as a more convenient model.

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.

Unique DUOX2+ACE2+ small cholangiocytes are pathogenic targets for primary biliary cholangitis

Cholangiocytes play a crucial role in bile formation. Cholangiocyte injury causes cholestasis, including primary biliary cholangitis (PBC). However, the etiology of PBC remains unclear despite being characterized as an autoimmune disease. Using single-cell RNA sequencing (scRNA-seq), fluorescence-activated-cell-sorting, multiplex immunofluorescence (IF) and RNAscope analyses, we identified unique DUOX2+ACE2+ small cholangiocytes in human and mouse livers. Their selective decrease in PBC patients was associated with the severity of disease. Moreover, proteomics, scRNA-seq, and qPCR analyses indicated that polymeric immunoglobulin receptor (pIgR) was highly expressed in DUOX2+ACE2+ cholangiocytes. Serum anti-pIgR autoantibody levels were significantly increased in PBC patients, regardless of positive and negative AMA-M2. Spatial transcriptomics and multiplex IF revealed that CD27+ memory B and plasma cells accumulated in the hepatic portal tracts of PBC patients. Collectively, DUOX2+ACE2+ small cholangiocytes are pathogenic targets in PBC, and preservation of DUOX2+ACE2+ cholangiocytes and targeting anti-pIgR autoantibodies may be valuable strategies for therapeutic interventions in PBC.

Hepatic TNFRSF12A promotes bile acid-induced hepatocyte pyroptosis through NFκB/Caspase-1/GSDMD signaling in cholestasis

Tumor necrosis factor receptor superfamily member-12A (TNFRSF12A) plays a critical role in inflammation and cell death. It is expressed in multiple tissues yet extremely low in normal liver. To date, little is known about its role in cholestasis. Therefore, we sought to delineate the role of TNFRSF12A in cholestasis and its underlying mechanisms. Human liver tissues were collected from patients with obstructive cholestasis (OC) or primary biliary cholangitis (PBC). Tnfrsf12a knockout (KO) mice were generated. Cholestasis was induced by bile-duct ligation (BDL) or 0.1% 5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-feeding. Human hepatoma PLC/PRF/5-ASBT and THP1 cell lines or primary mouse hepatocytes were used for mechanistic studies. Hepatic TNFRSF12A expression was markedly increased in OC or PBC patients. Genetic ablation of Tnfrsf12a in BDL- and 0.1%DDC-induced cholestatic mice significantly attenuated cholestatic liver injury with remarkable reduction of hepatocyte pyroptosis but without changing scores of necroptosis and apoptosis. Morphological features of hepatocyte pyroptosis and increased levels of pyroptosis-related proteins, NLRP3, cleaved-Caspase-1, and cleaved-GSDMD in OC patients and BDL-mice confirmed this observation. Further mechanistic studies revealed that bile acids (BAs) induced TNFRSF12A expression by enhancing the transcription factor c-JUN binding to the TNFRSF12A promoter and subsequently initiated hepatocyte pyroptosis by the NFκB/Caspase-1/GSDMD signaling. Interestingly, TWEAK, a typical ligand of TNFRSF12A, secreted by infiltrated macrophages in cholestatic livers, enhanced TNFRSF12A-induced hepatocyte pyroptosis. Taken together, we report, for the first time, that hepatic TNFRSF12A is dramatically increased in human cholestasis. Deletion of TNFRSF12A inhibits BAs-induced hepatocyte pyroptosis through the NFκB/Caspase-1/GSDMD signaling and thereby ameliorates cholestatic liver injury. As such, targeting TNFRSF12A could be a promising approach to treating cholestasis.

Optimal Tuning of Random Survival Forest Hyperparameter with an Application to Liver Disease

Background

Random Forest (RF) is a technique that optimises predictive accuracy by fitting an ensemble of trees to stabilise model estimates. The RF techniques were adapted into survival analysis to model the survival of patients with liver disease in order to identify biomarkers that are highly influential in patient prognostics.

Methods

The methodology of this study begins by applying the classical Cox proportional hazard (Cox-PH) model and three parametric survival models (exponential, Weibull and lognormal) to the published dataset. The study further applied the supervised learning methods of Tuning Random Survival Forest (TRSF) parameters and the conditional inference Forest (Cforest) to optimally predict patient survival probabilities.

Results

The efficiency of these models was compared using the Akaike information criteria (AIC) and integrated Brier score (IBS). The results revealed that the Cox-PH model (AIC = 185.7233) outperforms the three classical models. We further analysed these data to observe the functional relationships that exist between the patient survival function and the covariates using TRSF.

Conclusion

The IBS result of the TRFS demonstrated satisfactory performance over other methods. Ultimately, it was observed from the TRSF results that some of the covariates contributed positively and negatively to patient survival prognostics.

Network Proximity-Based Drug Repurposing Strategy for Early and Late Stages of Primary Biliary Cholangitis

Primary biliary cholangitis (PBC) is a chronic, cholestatic, immune-mediated, and progressive liver disorder. Treatment to preventing the disease from advancing into later and irreversible stages is still an unmet clinical need. Accordingly, we set up a drug repurposing framework to find potential therapeutic agents targeting relevant pathways derived from an expanded pool of genes involved in different stages of PBC. Starting with updated human protein-protein interaction data and genes specifically involved in the early and late stages of PBC, a network medicine approach was used to provide a PBC "proximity" or "involvement" gene ranking using network diffusion algorithms and machine learning models. The top genes in the proximity ranking, when combined with the original PBC-related genes, resulted in a final dataset of the genes most involved in PBC disease. Finally, a drug repurposing strategy was implemented by mining and utilizing dedicated drug-gene interaction and druggable genome information knowledge bases (e.g., the DrugBank repository). We identified several potential drug candidates interacting with PBC pathways after performing an over-representation analysis on our initial 1121-seed gene list and the resulting disease-associated (algorithm-obtained) genes. The mechanism and potential therapeutic applications of such drugs were then thoroughly discussed, with a particular emphasis on different stages of PBC disease. We found that interleukin/EGFR/TNF-alpha inhibitors, branched-chain amino acids, geldanamycin, tauroursodeoxycholic acid, genistein, antioestrogens, curcumin, antineovascularisation agents, enzyme/protease inhibitors, and antirheumatic agents are promising drugs targeting distinct stages of PBC. We developed robust and transparent selection mechanisms for prioritizing already approved medicinal products or investigational products for repurposing based on recognized unmet medical needs in PBC, as well as solid preliminary data to achieve this goal.

DNA methylation profile of liver tissue in end-stage cholestatic liver disease

Aims:

In this methylome-wide association study of cholestatic liver diseases (primary sclerosing cholangitis and primary biliary cholangitis), the authors aimed to elucidate changes in methylome and pathway enrichment to identify candidate genes.

Patients & methods:

Reduced representation bisulfite sequencing was performed on liver tissue from 58 patients with primary sclerosing cholangitis (n = 13), primary biliary cholangitis (n = 20), alcoholic liver disease (n = 21) and live liver donors (n = 4). Pathway enrichment and network analysis were used to explore key genes/pathways.

Results:

Both cholestatic liver diseases were characterized by global hypomethylation, with pathway enrichment demonstrating distinct genes and pathways associated with the methylome.

Conclusions:

This novel study demonstrated that differential methylation in cholestatic liver disease was associated with unique pathways, suggesting it may drive disease pathogenesis.

While DNA is the permanent code that defines each living being, the epigenome comprises sequences attached to DNA that can change with the environment. This means that abnormal changes to the epigenome may lead to disease and that finding and treating these abnormalities may in turn help treat disease. In this study of liver tissue from individuals with two rare liver diseases, primary sclerosing cholangitis and primary biliary cholangitis, the authors found that the epigenome of these two conditions is distinct, suggesting that the epigenome is linked to the development of these conditions and may be the key to treating them.

Novel study in rare cholestatic liver diseases (primary sclerosing cholangitis and primary biliary cholangitis) shows unique methylome changes, which may lead to novel treatment opportunities.

Measurement properties of the PBC-40 and PBC-27: a Dutch validation study

Objective

Patients with primary biliary cholangitis (PBC) have an impaired health-related quality of life (HRQoL). Practice guidelines recommend evaluating the HRQoL in all patients with PBC. The aim of this study was to assess the reliability and validity of our Dutch translation of the PBC-40, a PBC-specific measure of the HRQoL.

Design

The PBC-40 was translated into Dutch following standardised forward–backward procedures. Participants received the Dutch PBC-40 and the RAND-36 (a validated Dutch version of the 36-Item Short Form Health Survey) through postal mail. The PBC-27 is an abridged version of the PBC-40. Internal consistency between the items within the PBC-40/PBC-27 domains was assessed by Cronbach’s alpha. In addition, score distributions were analysed on floor and ceiling effects. Construct validity was assessed by hypotheses testing using Pearson’s correlation between the PBC-40/PBC-27 domains and RAND-36 scales.

Results

177 patients with PBC were included. The mean age was 61.1 (SD 9.9) years and the majority of patients was female (n=164, 92.7%). From the 7080 PBC-40 items, 61 items (0.9%) were missing and 342 items (4.8%) were answered with the ‘does not apply’ option. Each PBC-40 domain had a Cronbach’s α of >0.70, with the highest in the domain fatigue (0.95). For the PBC-27, the lowest Cronbach’s α was 0.69. Floor effects were present in three domains (cognition 19.3%, itch 27.0% and social 25.0% (only for PBC-27)). No ceiling effects were observed. All domains were significantly correlated with the corresponding RAND-36 scale(s) (p<0.001 for all). The strongest correlation was between the PBC-40 domain fatigue and the RAND-36 vitality scale (r=−0.834).

Conclusion

Our findings demonstrate the reliability and validity of the Dutch PBC-40 and PBC-27 for the assessment of the HRQoL in patients with PBC. This PBC-specific measure can be used in Dutch-speaking patients with PBC for both research and clinical purposes.

Joint Analysis of Genetic Correlation, Mendelian Randomization and Colocalization Highlights the Bi-Directional Causal Association Between Hypothyroidism and Primary Biliary Cirrhosis

Background: Hypothyroidism and primary biliary cirrhosis (PBC) are often co-existed in observational epidemiological studies. However, the causal relationship between them remains unclear.

Methods: Genetic correlation, Mendelian randomization (MR) and colocalization analysis were combined to assess the potential causal association between hypothyroidism and PBC by using summary statistics from large-scale genome-wide association studies. Various sensitivity analyses had been conducted to assess the robustness and the consistency of the findings.

Results: The linkage disequilibrium score regression demonstrated significant evidence of shared genetic architecture between hypothyroidism and PBC, with the genetic correlation estimated to be 0.117 (p = 0.006). The OR of hypothyroidism on PBC was 1.223 (95% CI, 1.072–1.396; p = 2.76 × 10⁻³) in MR analysis with inverse variance weighted (IVW) method. More importantly, the results from other 7MR methods with different model assumptions, were almost identical with that of IVW, suggesting the findings were robust and convincing. On the other hand, PBC was also causally associated with hypothyroidism (OR, 1.049; 95% CI, 1.010–1.089; p = 0.012), and, again, similar results can also be obtained from other MR methods. Various sensitivity analyses regarding the outlier detection and leave-one-out analysis were also performed. Besides, colocalization analysis suggested that there existed shared causal variants between hypothyroidism and PBC, further highlighting the robustness of the results.

Conclusion: Our results suggest evidence for the bi-directional causal association between hypothyroidism and PBC, which may provide insights into the etiology of hypothyroidism and PBC as well as inform prevention and intervention strategies directed toward both diseases.

Recent advances in clinical practice: epidemiology of autoimmune liver diseases

Autoimmune liver diseases are chronic inflammatory hepatobiliary disorders that when classically defined encompass three distinctive clinical presentations; primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH). Meaningful changes in disease epidemiology are reported, with increasing incidence and prevalence of AIH and PSC in Europe, and rising prevalence of PBC across Europe, North America and the Asia-Pacific region. However, there appears to be very significant global variation with contemporary incidence rates of disease per 100 000 ranging from 0.84 to 2.75 for PBC, 0.1 to 4.39 for PSC and 0.4 to 2.39 for AIH. Prevalence corresponds, and per 100 000 estimates for PBC range from 1.91 to 40.2, for PSC between 0.78 and 31.7 and for AIH from 4.8 to 42.9. Population-based studies and multicentre observational cohort series provide improved understanding of the clinical course that patients experience, highlighting variations in presenting phenotypes geographically and temporally. Collectively, while autoimmune liver diseases are rare, the clinical burden is disproportionately high relative to population incidence and prevalence. Age, sex and race also impact clinical outcomes, and patient morbidity and mortality are reflected by high need for gastroenterology, hepatology and organ transplant services.

Unilateral Trigeminal Sensory Neuropathy with Sjögren's Syndrome with Liver and Renal Impairment

Liver and renal involvement is a rare event in Sjögren’s syndrome. Sjögren’s syndrome is characterized by the progressive immune-mediated destruction of epithelial tissues of the salivary and lacrimal glands. Sensory ganglionitis, accompanied by T-cell invasion, occurs in patients with Sjögren’s syndrome, resulting in sensory neuropathy of the face or limbs. Patients are assessed by quantitative sensory testing. A 76-year-old woman presented with numbness of her left face and was subsequently diagnosed with Sjögren’s syndrome and primary biliary cirrhosis, and was found to have renal failure. Detection of her serum anti-Ro/SSA antibody was strongly positive. Shirmer’s test or a salivary volume in the gum test also showed positive results. Her somatosensory disturbance severity was higher in the trigeminal area than in the forearm, suggesting that the trigeminal nerve is more susceptible than other parts of the nervous system in patients with Sjögren’s syndrome and primary biliary cirrhosis. A simple sensory test could be performed during regular check-ups, as sensory deficits might develop after patients are diagnosed with Sjögren’s syndrome and primary biliary cirrhosis.

Primary biliary cirrhosis-autoimmune hepatitis overlap syndrome in a patient with paroxysmal nocturnal hemoglobinuria: a case report

Primary biliary cirrhosis (PBC)–autoimmune hepatitis (AIH) overlap syndrome is frequently associated with extrahepatic autoimmune disorders. Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired disease that is characterized by complement-mediated hemolysis due to erythrocyte membrane defects. However, autoimmune liver disease was not previously reported to be associated with PNH. A 37-year-old female patient was referred to our hospital with elevated liver enzymes and hematuria. On the basis of the symptoms and results of laboratory tests, radiographic studies, and pathologic results, she was diagnosed with PBC–AIH overlap syndrome and PNH. She was treated with a combination of ursodeoxycholic acid and prednisolone. The patient was symptom-free, with laboratory findings within near-normal range. The patient had recovered well at the 24-month follow-up evaluation. While we acknowledge that this was a single case, these findings expand our knowledge of immunological diseases that are associated with PNH and suggest an immune-mediated pathogenic pathway between PNH and PBC–AIH overlap syndrome. The combination of ursodeoxycholic acid and prednisolone can achieve therapeutic success. Routine follow-up of these patients is necessary to document disease progression.

Short-chain fatty acid and fecal microbiota profiles are linked to fibrosis in primary biliary cholangitis

The gut microbiota and metabolome could play a role in primary biliary cholangitis (PBC) progression. We aimed to assess fecal microbiota and fecal short-chain fatty acids (SCFAs) in PBC according to fibrosis. In a cross-sectional study of 23 PBC patients, fecal microbiota and SCFAs were determined using 16S rRNA sequencing and nuclear magnetic resonance spectroscopy, respectively. Fecal acetate and SCFAs were higher in advanced fibrosis. Advanced fibrosis microbiota exhibited decreased alpha diversity, increased Weisella and a distinct community composition. SCFAs correlated with individual taxa in non-advanced fibrosis. Fecal microbiota and SCFAs correspond to fibrosis in PBC.

Autoimmune Hepatitis-Primary Biliary Cholangitis Overlap Syndrome Triggered by COVID-19

COVID-19, caused by severe acute respiratory syndrome coronavirus 2 infection, has caused the ongoing global pandemic. Initially considered a respiratory disease, it can manifest with a wide range of complications (gastrointestinal, neurological, thromboembolic and cardiovascular) leading to multiple organ dysfunction. A range of immune complications have also been described. We report the case of a 57-year-old man with a medical history of hypertension, prediabetes and beta thalassemia minor, who was diagnosed with COVID-19 and subsequently developed fatigue and arthralgias, and whose blood work showed hyperferritinemia, elevated liver enzymes (AST/ALT/GGT), hypergammaglobulinemia, anti-smooth muscle antibody, anti-mitochondrial antibody, and anti-double-stranded DNA antibodies. The patient was diagnosed with autoimmune hepatitis-primary biliary cholangitis overlap syndrome triggered by COVID-19. To our knowledge, this is the first such case reported.

LEARNING POINTS

COVID-19 can precipitate a wide range of immune complications; we report a case of autoimmune hepatitis-primary biliary cholangitis overlap syndrome triggered by COVID-19.Clinicians should be aware of this unusual manifestation of COVID-19 so that prompt and appropriate diagnostic and therapeutic interventions can be initiated if the syndrome is suspected or confirmed.Our case further suggests the necessity for continued and regular follow-up of patients who have recovered from COVID-19 in order to uncover the long-term effects of the novel virus.

Bile Acid Profiles Are Distinct among Patients with Different Etiologies of Chronic Liver Disease

A significant increase of bile acid (BA) levels has been recognized as a general metabolic phenotype of diverse liver diseases. Monitoring of BA profiles has been proposed for etiology differentiation on liver injury. Here, we quantitatively profiled serum BAs of healthy controls and 719 patients with chronic liver disease of five etiologies, hepatitis B virus (HBV), hepatitis C virus (HCV), nonalcoholic steatohepatitis (NASH), alcohol-induced liver disease (ALD), and primary biliary cirrhosis (PBC), and investigated the generality and specificity of different etiologies. The raw data have been deposited into MetaboLights (ID: MTBLS2459). We found that patients with HBV, HCV, and NASH appeared to be more similar, and ALD and PBC patients clustered together. BA profiles, consisting of a total concentration of the 21 quantified BAs [total BAs (TBAs)], 21 BA proportions, and 24 BA relevant variables, were highly different among the etiologies. Specifically, the total BAs was higher in ALD and PBC patients compared with the other three groups. The proportion of conjugated deoxycholates was the highest in HBV-infected patients. The ratio of 12α-hydroxylated (12α-OH) to non-12α-OH BAs was the highest in NASH patients. The proportion of taurine-conjugated BAs was the highest in ALD patients. For PBC patients, the proportion of ursodeoxycholate species was the highest, and the ratio of primary to secondary BAs was the lowest. Comparatively, the difference of BA profiles among cirrhosis patients was consistent but weaker than that of all patients. The correlations between BA profiles and clinical indices were also quite different in different pathological groups, both in all patients and in patients with cirrhosis. Overall, our findings suggested that BA compositions are distinct among patients with different etiologies of chronic liver disease, and some BA-relevant variables are of clinical potentials for liver injury type differentiation, although further validations on more etiologies and populations are needed.

Home-based exercise in patients with refractory fatigue associated with primary biliary cholangitis: a protocol for the EXerCise Intervention in cholesTatic LivEr Disease (EXCITED) feasibility trial

INTRODUCTION

Fatigue is the most commonly reported symptom of the liver disease primary biliary cholangitis (PBC). It affects 40%-80% of patients, has no effective treatment and is associated with heightened mortality risk. The pathogenesis is unknown, but muscle bioenergetic abnormalities have been proposed to contribute. Directly observed exercise has been shown to attenuate symptoms in small groups; however, due to the rare nature of the disease, home-based interventions need to be evaluated for feasibility, safety and efficacy.

METHODS AND ANALYSIS

This is a phase 1/pilot, single-arm, open-label clinical trial evaluating a novel home-based exercise programme in patients with PBC with severe fatigue. Forty patients with moderate-severe fatigue (PBC40 fatigue domain score >33; other causes of fatigue excluded) will be selected using a convenience sampling method. A 12-week home-based exercise programme, consisting of individualised resistance, aerobic exercises and telephone health calls (first 6 weeks only), will be delivered. Measures of fatigue (PBC40 fatigue domain; fatigue impact scale), quality of life, sleep (Epworth Sleep Score), physical activity, anxiety and depression, aerobic exercise capacity (incremental shuttle walk test; Duke Activity Status Index) and functional capacity (short physical performance battery) will be assessed at baseline and at 6 and 12 weeks following the intervention.

ETHICS AND DISSEMINATION

The protocol is approved by the National Research Ethics Service Committee London (IRAS 253115). Recruitment commenced in April 2019 and ended in March 2020. Participant follow-up is due to finish by December 2020. Findings will be disseminated through peer-reviewed publication, conference presentation and social media.

TRIAL REGISTRATION NUMBER

NCT04265235.

Primary biliary cholangitis-autoimmune hepatitis overlap syndrome: Case report and literature review

Paris criteria remain practical for retaining the diagnosis of overlap syndrome. While liver histology is mandatory, its absence should not be an obstacle to the diagnosis and delay the initiation of treatment in countries where biopsy not available.

Manganese and copper levels in patients with primary biliary cirrhosis and primary sclerosing cholangitis

The liver and the biliary tree form the main excretory route of manganese (Mn) and copper (Cu). Cholestasis, can lead to the accumulation of these trace elements in the organism, resulting in toxicity to the basal ganglia of the central nervous system. The aim of our study was to reveal the influence of long-term cholestasis on the Mn and Cu levels in the blood of patients with primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC). We recruited patients with PBC (n = 20) and PSC (n = 32). A control group (n = 40) was also set up. We also examined serum bile acid concentrations and liver enzyme activities. We did not observe any significant differences in any of these parameters between the PBC and PSC groups. The Mn and Cu levels in the PBC and PSC patients differed significantly from the that in the control group (p < 0.0001 and p < .021, respectively). Patients in whom the laboratory cholestasis markers normalized during ursodeoxycholic acid treatment (18/52;35%) presented with significantly lower levels of Mn and Cu (p = .015 and p = .012, respectively). Ten PSC patients showed normal levels of Mn and Cu six months after liver transplantation. Fine tremors, rigidity, dysarthria, and hypomimia were reported in nine (23%), eight (20%), four (10%), and eight (20%) patients, respectively. In addition to monitoring the cholestasis levels, liver function, and Mn and Cu levels during the long-term treatment of PBC and PSC patients, it is important to also regularly monitor the occurrence and development of extrapyramidal symptoms of Parkinson's-like syndromes.

The ursodeoxycholic acid response score predicts pathological features in primary biliary cholangitis

AIM

The ursodeoxycholic acid response score (URS) can predict the biochemical response to 12 months of ursodeoxycholic acid (UDCA) treatment in patients with primary biliary cholangitis (PBC). We investigated the relationship between the URS and the histopathological features before and after UDCA treatment.

METHODS

Patients with PBC (n = 126) were examined for the association between the probability of response (POR) to UDCA based on the URS formulas and clinicopathological features. Furthermore, 30 patients were examined for the association between the POR and pathological changes.

RESULTS

The POR area under the receiver operating characteristic curve (AUROC) for predicting the biochemical response to UDCA was 0.861. The PORs of stage 1 in the Nakanuma system and grade 0 in the CK7 grading in hepatocytes were significantly higher than those of stage 3 and grade 3, respectively. The AUROCs for the prediction of stage ≥2, stage ≥3 and stage 4 in the Nakanuma system at pretreatment were 0.592, 0.710 and 0.817, respectively. The AUROCs for the prediction of grade ≥1, grade ≥2 and grade 3 in the CK7 hepatocyte grading were 0.741, 0.824 and 0.970, respectively. Furthermore, the AUROC for predicting the histological stage progression after UDCA treatment in the Scheuer classification and the Nakanuma system were 0.712 and 0.799, respectively.

CONCLUSIONS

The URS not only predicts the biochemical response, but also reflects the Nakanuma system and the CK7 hepatocyte grading at pretreatment. This scoring system can identify an inadequate histological response to UDCA treatment in the Scheuer classification and the Nakanuma system.

[Sjogren's disease/syndrome in combination with autoimmune liver damage. 20-years observation]

Sjogren's disease (BS) is a systemic autoimmune disease, the main symptoms of which are associated with dry eyes, mouth, skin, respiratory and gastrointestinal tract, etc., but there are a large number of extra-vascular symptoms that can accompany this disease: weakness, swelling of the lymph nodes, respiratory failure, pain and swelling of the joints, rash, dysphagia, gastro-esophageal reflux, lymphoma, etc. In addition, the etiology of this disease remains unknown, and the pathogenesis is partially studied. The diagnosis of Sjogren's disease is complicated by a variety of clinical manifestations, as well as subacute and chronic variants of the course of the disease, in addition, the diagnostic criteria are periodically changed. It is recommended to adhere to the domestic diagnostic criteria considering the presence of laboratory signs of an autoimmune disease. The article presents a clinical observation of a patient with the development of the main symptoms and signs of BS and autoimmune hepatitis for 20 years. Recurrent mumps or chronic bilateral enlargement of the parotid salivary glands may be the first symptom of Sjogren's disease, which is recommended to extend the examination in order to identify other, sometimes latent signs of the disease.

Single Topic Conference on Autoimmune Liver Disease from the Canadian Association for the Study of the Liver

Autoimmune liver disease (AILD) spans a spectrum of chronic disorders affecting the liver parenchyma and biliary system. Three main categories of AILD are autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC), and primary sclerosing cholangitis (PSC). This review condenses the presentation and discussions of the Single Topic Conference (STC) on AILD that was held in Ottawa, Ontario, in November 2019. We cover generalities regarding disease presentation and clinical diagnosis; mechanistic themes; treatment paradigms; clinical trials, including approaches and challenges to new therapies; and looking beyond traditional disease boundaries. Although these diseases are considered autoimmune, the etiology and role of environmental triggers are poorly understood. AILDs are progressive and chronic conditions that affect survival and quality of life. Advances have been made in PBC treatment because second-line treatments are now available (obeticholic acid, bezafibrate); however, a significant proportion still present suboptimal response. AIH treatment has remained unchanged for several decades, and data suggest that fewer than 50% of patients achieve a complete response and as many as 80% develop treatment-related side effects. B-cell depletion therapy to treat AIH is in an early stage of development and has shown promising results. An effective treatment for PSC is urgently needed. Liver transplant remains the best option for patients who develop decompensated cirrhosis or hepatocellular carcinoma within specific criteria, but recurrent AILD might occur. Continued efforts are warranted to develop networks for AILD aimed at assessing geo-epidemiological, clinical, and biochemical differences to capture the new treatment era in Canada.

A case of gastric cardia telangiectasias and primary biliary cirrhosis with hemorrhage

In patients presenting with persistent anemia and gastric cardia telangiectasias, a potential etiology of portal hypertension due to chronic liver disease, especially primary biliary cirrhosis, should be considered. Drugs for treating specific liver disease and lowering portal hypertension are effective strategies to prevent hemorrhage.

Validity of an Automated Algorithm to Identify Cirrhosis Using Electronic Health Records in Patients with Primary Biliary Cholangitis

Background

Biopsy remains the gold standard for determining fibrosis stage in patients with primary biliary cholangitis (PBC), but it is unavailable for most patients. We used data from the 11 US health systems in the FibrOtic Liver Disease Consortium to explore a combination of biochemical markers and electronic health record (EHR)-based diagnosis/procedure codes (DPCs) to identify the presence of cirrhosis in PBC patients.

Methods

Histological fibrosis staging data were obtained from liver biopsies. Variables considered for the model included demographics (age, gender, race, ethnicity), total bilirubin, alkaline phosphatase, albumin, aspartate aminotransferase (AST) to platelet ratio index (APRI), Fibrosis 4 (FIB4) index, AST to alanine aminotransferase (ALT) ratio, and >100 DPCs associated with cirrhosis/decompensated cirrhosis, categorized into ten clusters. Using least absolute shrinkage and selection operator regression (LASSO), we derived and validated cutoffs for identifying cirrhosis.

Results

Among 4328 PBC patients, 1350 (32%) had biopsy data; 121 (9%) were staged F4 (cirrhosis). DPC clusters (including codes related to cirrhosis and hepatocellular carcinoma diagnoses/procedures), Hispanic ethnicity, ALP, AST/ALT ratio, and total bilirubin were retained in the final model (AUROC=0.86 and 0.83 on learning and testing data, respectively); this model with two cutoffs divided patients into three categories (no cirrhosis, indeterminate, and cirrhosis) with specificities of 81.8% (for no cirrhosis) and 80.3% (for cirrhosis). A model excluding DPCs retained ALP, AST/ALT ratio, total bilirubin, Hispanic ethnicity, and gender (AUROC=0.81 and 0.78 on learning and testing data, respectively).

Conclusion

An algorithm using laboratory results and DPCs can categorize a majority of PBC patients as cirrhotic or noncirrhotic with high accuracy (with a small remaining group of patients' cirrhosis status indeterminate). In the absence of biopsy data, this EHR-based model can be used to identify cirrhosis in cohorts of PBC patients for research and/or clinical follow-up.

Levels of serum IgG subclasses in patients with liver disease: A retrospective study

Viral and alcoholic liver disease, drug induced liver disease (DILD), primary biliary cirrhosis (PBC) and autoimmune hepatitis (AIH) are among the most common liver diseases observed in clinical practice. These diseases lack unique clinical characteristics at the beginning of pathogenesis, which renders specific diagnosis difficult. Immunoglobulin G (IgG) subclasses are the main isoform of antibodies that can be found in the serum that serve important protective roles in immunity. The present study aimed to investigate the serum IgG subclass distribution in patients with the five common liver diseases aforementioned. The present study retrospectively recorded and analyzed the serum IgG subclass levels of different patients, who were grouped according to their clinical diagnosis. Serum IgG subclass levels were measured using immunonephelometric assays. IgG3 levels were found to be significantly increased whereas IgG4 levels were significantly decreased in patients with PBC. In patients with AIH, IgG1 levels were significantly increased. By contrast, IgG1/IgG level ratios in patients with viral liver disease were significantly increased. No clear pattern in the distribution characteristics of IgG subclasses could be observed in cohorts with alcoholic liver disease and DILD in the present study. Additionally, model for end-stage liver disease scores regarding IgG1 in patients with AIH shared a synergistic relationship. Anti-mitochondrial antibody subtype M2 (AMA-M2) and IgG3 in patients with PBC demonstrated a synergistic relationship. These results suggested that IgG subclasses may be used as biomarkers to further the understanding of liver disease, which could allow for early diagnosis.

Treatment of primary biliary cirrhosis with ursodeoxycholic acid combined with traditional Chinese medicine: A protocol for systematic review and meta analysis

OBJECTIVE

Ursodeoxycholic acid is the priority drug of primary biliary cirrhosis (PBC) and is usually combined with traditional Chinese medicine. This study aimed to systematically evaluate the benefits of integrated Chinese and western interventions for PBC.

METHODS

Searched the randomized controlled trials in PubMed, Web of Science, CNKI, CBM, Wanfang, VIP databases. The Cochrane risk of bias tool was used for methodological quality assessment and all data analysis was performed using Revman5.3 and Stata14.2 software.

RESULT

30 randomized controlled trials involving 10 interventions with a total of 1948 participants were included. Identified the direct and indirect evidence of trials, and used network meta analyses ranked the benefits of different interventions based on pairwise meta analysis. The primary outcom was clinical efficacy rate. Secondary outcome was liver function, including alkaline phosphataseand total bilirubin.

CONCLUSION

The conclusion of this systematic review provide credible evidence - based for the relative advantages of integrated Chinese and western interventions for PBC.

Normal alkaline phosphatase levels are dependent on race/ethnicity: NationalGEP Health and Nutrition Examination Survey data

OBJECTIVE

The range of normal serum alkaline phosphatase is not well defined. We used data from the National Health and Nutrition Examination Survey from 2009 to 2016 to generate normal ranges for a racially diverse sample of healthy adults.

METHODS

Respondents 18 years or older were included. Conditions known to elevate alkaline phosphatase were cause for exclusion. Alkaline phosphatase was measured using a colorimetric method based on standardised National Health and Nutrition Examination Survey protocols. Because alkaline phosphatase values were not normally distributed, log transformation was used. We calculated upper limits of normal (97.5 percentile), stratified by sex and race/ethnicity, and 90% CIs for the upper limits of normal.

RESULTS

1199 respondents (673 female, 526 male) had body mass index from 18.5 to less than 25. Upper limits of normal were highest among Hispanics (123.2 IU/L (90% CI 110.2 to 136.7) for females; 123.8 IU/L (90% CI 112.0 to 135.1) for males), followed by African Americans (109.9 IU/L (90% CI 97.3 to 122.4) for females; 116.3 IU/L (90% CI 105.0 to 126.1) for males) and whites (97.1 IU/L (90% CI 91.0 to 103.4) for females; 109.6 IU/L (90% CI 102.1 to 116.3) for males). Asian American/Pacific Islander respondents had the lowest results: 93.8 IU/L (90% CI 88.2 to 99.5) for females and 95.3 IU/L (90% CI 88.1 to 102.1) for males.

CONCLUSIONS

The upper limit of normal alkaline phosphatase varies by race/ethnicity in a large US sample with body mass index of 18.5<25.

Transverse myelitis associated with primary biliary cirrhosis: clinical, laboratory, and neuroradiological features

PURPOSE

Only five patients diagnosed with transverse myelitis (TM) associated with primary biliary cirrhosis (PBC) have been reported in the literature to date. We report two additional patients with TM associated with PBC at our hospital and review all seven cases.

MATERIALS AND METHODS

An association between neuromyelitis optic spectrum disease (NMOSD) and PBC is reported for the first time in one of our patients. The second patient was diagnosed with TM associated with PBC without Sjögren's syndrome (SS). A literature review was performed using the PubMed database.

RESULTS

All patients diagnosed with TM associated with PBC were female with a median age of 53 years. TM was associated with SS in 71.4% of the patients. Complete TM and incomplete TM were diagnosed in 71.4% and 28.6% of the patients. The erythrocyte sedimentation rate was increased in 83.3% of patients. All patients were positive for anti-mitochondrial antibodies. Other autoantibodies, including anti-nuclear antibodies, rheumatoid factor, anti-SSA antibody, were detected in some patients. Cerebrospinal fluid analysis was abnormal in 83.3% of patients. The spinal cord lesions involved more than three vertebral segments in 85.7% of patients. Glucocorticoids were administered in 85.7% of patients, and good responses were observed.

CONCLUSIONS

The association between TM and PBC may be missed by neurologists. More attention should be paid to the association between NMOSD and PBC. Most patients show SS and may experience relapse, and there is a good rationale for early commencement of immunosuppressive therapy.

TGF-β2 silencing to target biliary-derived liver diseases

OBJECTIVE

TGF-β2 (TGF-β, transforming growth factor beta), the less-investigated sibling of TGF-β1, is deregulated in rodent and human liver diseases. Former data from bile duct ligated and MDR2 knockout (KO) mouse models for human cholestatic liver disease suggested an involvement of TGF-β2 in biliary-derived liver diseases.

DESIGN

As we also found upregulated TGFB2 in liver tissue of patients with primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC), we now fathomed the positive prospects of targeting TGF-β2 in early stage biliary liver disease using the MDR2-KO mice. Specifically, the influence of TgfB2 silencing on the fibrotic and inflammatory niche was analysed on molecular, cellular and tissue levels.

RESULTS

TgfB2-induced expression of fibrotic genes in cholangiocytes and hepatic stellate cellswas detected. TgfB2 expression in MDR2-KO mice was blunted using TgfB2-directed antisense oligonucleotides (AON). Upon AON treatment, reduced collagen deposition, hydroxyproline content and αSMA expression as well as induced PparG expression reflected a significant reduction of fibrogenesis without adverse effects on healthy livers. Expression analyses of fibrotic and inflammatory genes revealed AON-specific regulatory effects on Ccl3, Ccl4, Ccl5, Mki67 and Notch3 expression. Further, AON treatment of MDR2-KO mice increased tissue infiltration by F4/80-positive cells including eosinophils, whereas the number of CD45-positive inflammatory cells decreased. In line, TGFB2 and CD45 expression correlated positively in PSC/PBC patients and localised in similar areas of the diseased liver tissue.

CONCLUSIONS

Taken together, our data suggest a new mechanistic explanation for amelioration of fibrogenesis by TGF-β2 silencing and provide a direct rationale for TGF-β2-directed drug development.

Number needed to treat with ursodeoxycholic acid therapy to prevent liver transplantation or death in primary biliary cholangitis

OBJECTIVE

The clinical benefit of ursodeoxycholic acid (UDCA) in primary biliary cholangitis (PBC) has never been reported in absolute measures. The aim of this study was to assess the number needed to treat (NNT) with UDCA to prevent liver transplantation (LT) or death among patients with PBC.

METHODS

The NNT was calculated based on the untreated LT-free survival and HR of UDCA with respect to LT or death as derived from inverse probability of treatment weighting-adjusted Cox proportional hazard analyses within the Global PBC Study Group database.

RESULTS

We included 3902 patients with a median follow-up of 7.8 (4.1-12.1) years. The overall HR of UDCA was 0.46 (95% CI 0.40 to 0.52) and the 5-year LT-free survival without UDCA was 81% (95% CI 79 to 82). The NNT to prevent one LT or death within 5 years (NNT5y) was 11 (95% CI 9 to 13). Although the HR of UDCA was similar for patients with and without cirrhosis (0.33 vs 0.31), the NNT5y was 4 (95% CI 3 to 5) and 20 (95% CI 14 to 34), respectively. Among patients with low alkaline phosphatase (ALP) (≤2× the upper limit of normal (ULN)), intermediate ALP (2-4× ULN) and high ALP (>4× ULN), the NNT5y to prevent one LT or death was 26 (95% CI 15 to 70), 11 (95% CI 8 to 17) and 5 (95% CI 4 to 8), respectively.

CONCLUSION

The absolute clinical efficacy of UDCA with respect to LT or death varied with baseline prognostic characteristics, but was high throughout. These findings strongly emphasise the incentive to promptly initiate UDCA treatment in all patients with PBC and may improve patient compliance.

Patient ownership of primary biliary cholangitis long-term management

OBJECTIVE

Patient ownership of disease is vital in rare diseases like primary biliary cholangitis (PBC). This survey of UK members of the PBC foundation aimed to assess patients' perception of their disease management, focusing on key biomarkers and problematic symptoms.

DESIGN

Registered PBC foundation members were surveyed on their experiences on their most recent clinic visit, covering the type of hospital and clinician and whether biochemical response and symptom burden were discussed, including who initiated these conversations. Respondents were also asked about their willingness to initiate these conversations.

RESULTS

Across 633 respondents, 42% remembered discussing alkaline phosphatase, the key biochemical response measure, and the majority of discussions were initiated by the healthcare provider. 56% of respondents remembered discussing itch, a key PBC symptom. There was no distinction between the grade of healthcare professional, but both patients and clinicians were significantly more likely to discuss symptoms over disease progression. Reassuringly, 84% of respondents felt willing to initiate conversations about their illness, regardless of the grade of managing clinician.

CONCLUSIONS

This work lays a positive foundation for patient education and empowerment projects, likely to improve clinical outcomes. Key aspects of management (biochemical response to treatment and symptom burden) should be emphasised as topics of discussion to both patients and clinicians managing PBC. We suggest a simple cue card to prompt patient-led discussion.

Endocrine Autoimmune Disease as a Fragility of Immune Surveillance against Hypersecreting Mutants

Some endocrine organs are frequent targets of autoimmune attack. Here, we addressed the origin of autoimmune disease from the viewpoint of feedback control. Endocrine tissues maintain mass through feedback loops that balance cell proliferation and removal according to hormone-driven regulatory signals. We hypothesized the existence of a dedicated mechanism that detects and removes mutant cells that missense the signal and therefore hyperproliferate and hypersecrete with potential to disrupt organismal homeostasis. In this mechanism, hypersecreting cells are preferentially eliminated by autoreactive T cells at the cost of a fragility to autoimmune disease. The "autoimmune surveillance of hypersecreting mutants" (ASHM) hypothesis predicts the presence of autoreactive T cells in healthy individuals and the nature of self-antigens as peptides from hormone secretion pathway. It explains why some tissues get prevalent autoimmune disease, whereas others do not and instead show prevalent mutant-expansion disease (e.g., hyperparathyroidism). The ASHM hypothesis is testable, and we discuss experimental follow-up.

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.

Increasing prevalence of primary biliary cholangitis in Victoria, Australia

BACKGROUND AND AIM

The prevalence of primary biliary cholangitis (PBC) reported in different countries varies significantly and in some parts of the world appears to be increasing. The aim of this study was to determine the 2013 prevalence of PBC in Victoria, Australia, and to determine the time trend by comparing it with previous studies undertaken in 1991 and 2002.

METHODS

Four case-finding methods were used to identify cases of PBC in Victoria: (1) physicians' survey; (2) tertiary hospital search; (3) liver transplant database search; and (4) private pathology antimitochondrial antibody search.

RESULTS

The prevalence of PBC in Victoria, Australia, is 189.0 per million using all four methods. The average annual increase in prevalence from 1991 to 2013 was 7.7 per million per year. Using the same case-finding methods as the 1991 Victorian prevalence study (methods 1 and 2), the prevalence of PBC increased from 19.1 per million in 1991 to 49.4 per million in 2002 (P < 0.001) and to 80.7 per million in 2013 (P < 0.001).

CONCLUSIONS

The current prevalence of PBC in Victoria is significantly higher than previously reported. The use of private pathology-based case-finding methods is important in identifying the maximum number of PBC cases.

The use of biologics in the treatment of autoimmune liver disease

Introduction: Autoimmune liver diseases include autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC) and juvenile autoimmune hepatitis (JAIH). The pathophysiologic features of each disease vary, but generally include presence of autoantibodies, cytokine abnormalities, and/or T and B cell autoreactivity.Areas covered: This article compares conventional therapy with newer biologics available for treatment of autoimmune liver diseases. Conventional therapy involves the use of immunosuppressive agents, or other treatment modalities for specific autoimmune liver diseases such as ursodeoxycholic acid and fibrates for PBC. Biologics were developed to target the production of autoantibodies by B cells, the presence of proinflammatory cytokines, adhesion molecules or T and B cell activation.Expert opinion: Despite the promise of biologics being able to target specific cellular and humoral pathways, results have been generally poor, and safety has not been as expected. Cases of autoimmune hepatitis have also developed with the use of these biologicals. Reasons for the lack of success of biologics in treating autoimmune liver disease has led to a reevaluation of our understanding of underlying pathogenesis, demonstrating that while our knowledge of the immunity has improved over the past two decades, it is far from complete.

Chronic Inflammatory Diseases at Secondary Sites Ensuing Urogenital or Pulmonary Chlamydia Infections

Chlamydia trachomatis and C. pneumoniae are members of the Chlamydiaceae family of obligate intracellular bacteria. The former causes diseases predominantly at the mucosal epithelial layer of the urogenital or eye, leading to pelvic inflammatory diseases or blindness; while the latter is a major causative agent for pulmonary infection. On top of these well-described diseases at the respective primary infection sites, Chlamydia are notoriously known to migrate and cause pathologies at remote sites of a host. One such example is the sexually acquired reactive arthritis that often occurs at few weeks after genital C. trachomatis infection. C. pneumoniae, on the other hand, has been implicated in an extensive list of chronic inflammatory diseases which include atherosclerosis, multiple sclerosis, Alzheimer’s disease, asthma, and primary biliary cirrhosis. This review summarizes the Chlamydia infection associated diseases at the secondary sites of infection, and describes the potential mechanisms involved in the disease migration and pathogenesis.

Fluctuations of antimitochondrial antibodies and anti-gp210 antibody in a patient with primary biliary cholangitis and Sjögren syndrome with subsequent autoimmune hemolytic anemia: A case report

RATIONALE

Primary biliary cholangitis (PBC) is a rare autoimmune cholestatic liver disease. It is often associated with extrahepatic autoimmune disorders. However, the concurrence of PBC and Sjögren syndrome (SS) with the subsequent onset of autoimmune hemolytic anemia (AIHA) is extremely rare.

PATIENT CONCERNS

This study investigated a 60-year-old woman admitted to our hospital with complaints of xerostomia for 5 years, pruritus for 3 years, and abnormal liver function for 3 months.

DIAGNOSES

The patient was suffering from typical clinical PBC and SS, and developed decompensated liver cirrhosis after 32 months of ursodeoxycholic acid (UDCA) therapy. In May 2018, she was readmitted to the hospital with a high fever of 39 °C, coughing, and sever fatigue without remission after 3 days of cephalosporin antibiotic therapy. During the clinical course of PBC, her antimitochondrial antibodies (AMA) titers fluctuated from 1:1000 to negative and then to weakly positive, determined by indirect immunofluorescence (IIF), immunoblotting, and enzyme-linked immunosorbent assay (ELISA) based on recombinant mitochondrial antigens; furthermore, her titers of anti-gp210, an antinuclear antibody (ANA), increased sharply. Laboratory tests and imaging were performed to diagnose PBC and SS in September 2015. However, she was subsequently diagnosed with AIHA after 32 months of UDCA therapy based on the identification of pancytopenia, increased reticulocyte (RET) count, and a positive result from the direct Coombs test.

INTERVENTIONS

UDCA, hepatic protectant, albumin infusion, chest drainage, rational antibiotic use, diuretics, and methylprednisolone were used to treat the patient.

OUTCOMES

Liver cirrhosis was complicated by the development of AIHA, which became severe at 42 months of follow-up.

LESSONS

This is the first case report showing a patient with comorbid PBC and SS, as well as the sequential development of AIHA with decreased AMA and increased anti-gp210 titers; this may have been due to immunodeficiency. These findings stress the importance of the serological screening of ANA profile, as well as repeated measurement of ANA and AMA to track PBC progression and prognosis.

Hyperlipidaemia in primary biliary cholangitis: treatment, safety and efficacy

Primary biliary cholangitis (PBC) is an autoimmune liver disease associated with altered lipoprotein metabolism, mainly cholesterol. Hypercholesterolaemia, a major modifiable risk factor for cardiovascular disease in the general population, occurs in 75%-95% of individuals with PBC. The impact of hypercholesterolaemia on cardiovascular risk in PBC, however, is controversial. Previous data have shown that hypercholesterolaemia in PBC is not always associated with an increase in cardiovascular events. However, patients with PBC with cardiovascular risk factors may still warrant cholesterol-lowering therapy. Treatment of hypercholesterolaemia in PBC poses unique challenges among primary care providers due to concerns of hepatotoxicity associated with cholesterol-lowering medications. This review summarises the current understanding of the pathophysiology of hypercholesterolaemia in PBC and its pertinent cardiovascular risk. We will also discuss indications for treatment and the efficacy and safety of available agents for hypercholesterolaemia in PBC.