Pulmonary hypertension in primary biliary cirrhosis: a prospective study in 178 patients

Glomerulonephritis in primary biliary cholangitis in China: an important complication

BACKGROUND

Extrahepatic manifestations in patients with primary biliary cholangitis (PBC) are frequently observed recently. We aimed in this study to explore the clinicopathological characteristics and prognosis of glomerulonephritis in patients with PBC.

METHODS

Consecutive PBC patients admitted to Peking Union Medical College Hospital from January 2002 to May 2019 were retrospectively enrolled. PBC patients with other autoimmune diseases which may have nephritis were excluded. Structured interview, systemic rheumatologic examination, and laboratory tests were conducted for each patient. Literature about patients with PBC and glomerulonephritis was reviewed and summarized.

RESULTS

Among the 330 PBC patients enrolled, glomerulonephritis were identified in 10 patients (3.0%). Eight (80.0%) were females and 2 (20.0%) were males. The mean age was 58.4 ± 9.5 years old. Membranous nephropathy (MN) was revealed in 4 patients, IgA nephropathy (IgA N) in 2 patients, minimal change disease (MCD) in 2 patients, mesangial proliferative glomerulonephritis in 1 patient, and renal amyloidosis in 1 patient. Compared to the literature reviewed, 10 cases of MN, 1 case of MCD, 1 case of IgA N, and 1 case of acute poststreptococcal glomerulonephritis (APSGN) were observed.

CONCLUSIONS

Glomerulonephritis may not be a well-recognized feature of PBC and is not a rare complication and deserved to be routinely screened in clinical practice. As MN is the most common form of glomerulonephritis in PBC patients and PBC can be asymptomatic at an early stage, patients presented with MN should be screened for PBC, so to avoid cirrhosis. Key Points • Patients with primary biliary cholangitis (PBC) can be complicated with glomerulonephritis, and membranous nephropathy (MN) is the most common form.

Genetic link between primary biliary cholangitis and connective tissue diseases in European populations: A two-sample Mendelian randomization study

BACKGROUND

An association between primary biliary cholangitis (PBC) and connective tissue diseases (CTDs) [rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Sjögren's syndrome (SS), systemic sclerosis (SSc)] has been found in observational studies. However, the direction causality is unclear. The aim of this study was to assess the causality between PBC and CTDs and to promote early screening, pre-emptive therapy, and accurate stratification.

METHODS

A two-sample Mendelian randomization (MR) analysis was performed to assess the causal relationship between PBC [Genome-Wide Association Study (GWAS) meta-analysis, 8021 cases/16498 controls], and SLE (GWAS meta-analysis, 8021 cases/16489 controls), RA(FinnGen, 6236 cases/14727 controls), SS(FinnGen, 2495 cases/365533 controls), SSc (FinnGen, 302 cases/213145 controls). Inverse variance weighting (IVW) was used as the primary analysis method, supplemented by four sensitivity analyses to assess the robustness of the results.

RESULTS

The IVW revealed that genetically predicted PBC increased the risk of SLE [odd's ratio (OR) = 1.43, 95% confidence interval (CI) 1.30-1.58, P < 0.001]), RA (OR = 1.09, 95%CI1.04-1.14, P<0.001), and SS (OR = 1.18, 95%CI1.12-1.24, P<0.001), but not that of SSc. In addition, no association was observed between CTDs as an exposure and PBC. Sensitivity analyses did not reveal horizontal pleiotropy.

CONCLUSIONS

Our study provided new genetic evidence for a causal relationship between PBC and CTDs. PBC increased the risk of SLE, RA, and SS. Our findings highlighted the importance of active screening and intervention for CTDs in patients with PBC.

Portopulmonary Hypertension

PoPH is a well-recognized complication of portal hypertension with or without cirrhosis and is classified as a subset of PAH. Identification of PoPH is crucial as it has a major impact on prognosis and liver transplant candidacy. Echocardiogram is the initial screening tool of choice and the patient should proceed to RHC for confirmation. PAH-directed therapy is the treatment of choice, allowing the patient to achieve a hemodynamic threshold to undergo a liver transplant safely.

CXCL12-CXCR4-Mediated Chemotaxis Supports Accumulation of Mucosal-Associated Invariant T Cells Into the Liver of Patients With PBC

Objectives: To explore the potential role of CD3⁺CD8⁺CD161^high TCRVα7.2⁺ mucosal-associated invariant T (MAIT) cells in the pathogenesis of primary biliary cholangitis (PBC).

Methods: We enrolled 55 patients with PBC, 69 healthy controls (HCs), and 8 patients with hepatic hemangioma. Circulating MAIT cells and their chemokine receptor profiles and cytokine production were quantified using flow cytometry. Liver-resident MAIT cells were examined by immunofluorescence staining. CXCL12-mediated chemotaxis of MAIT cells was measured using a transwell migration assay. Plasma interleukin (IL)-18 was measured using ELISA, and cytokine production in IL-18-stimulated MAIT cells was detected using flow cytometry.

Result: Peripheral MAIT cells were found to be significantly lower in patients with PBC (3.0 ± 3.2% vs. 9.4 ± 8.0%, p < 0.01) and negatively correlated with alkaline phosphatase (ALP) levels (r = −0.3209, p < 0.05). Liver immunofluorescence staining suggested that MAIT cells might accumulate in PBC liver. MAIT cells from patients with PBC expressed higher levels of CXCR4 (84.8 ± 18.0% vs. 58.7 ± 11.4%, p < 0.01), and the expression of CXCL12 was higher in PBC liver. CXCL12 promoted MAIT cell chemotaxis (70.4 ± 6.8% vs. 52.2 ± 3.5%, p < 0.01), which was attenuated by CXCR4 antagonist. MAIT cells from PBC produced significantly more interferon-γ (IFN-γ) (88.3 ± 4.2% vs. 64.2 ± 10.1%, p < 0.01), tumor necrosis factor-α (TNF-α) (93.0 ± 1.1% vs. 80.1 ± 5.3%, p < 0.01), Granzyme B (89.3 ± 3.3% vs. 72.1 ± 7.0%, p < 0.01), and perforin (46.8 ± 6.6% vs. 34.8 ± 7.7%, p < 0.05). MAIT cells from PBC expressed higher levels of IL18-Rα (83.8 ± 10.2% vs. 58.3 ± 8.7%, p < 0.01). Plasma IL-18 was more abundant in patients with PBC (286.8 ± 75.7 pg/ml vs. 132.9 ± 78.1 pg/ml, p < 0.01). IL-18 promoted IFN-γ production in MAIT cells (74.9 ± 6.6% vs. 54.7 ± 6.7%, p < 0.01), which was partially attenuated by blocking IL-18R (68.6 ± 8.3% vs. 43.5 ± 4.2%, p < 0.01).

Conclusion: Mucosal-associated invariant T cells from patients with PBC accumulated in the liver via CXCL12-CXCR4-mediated chemotaxis, produced pro-inflammatory cytokines, and contributed to portal inflammation, which was potentially mediated by elevated IL-18. Targeting MAIT cells might be a therapeutic approach for PBC.

Anti-mitochondrial Antibodies in Patients with Dilated Cardiomyopathy

Objective It has been reported that anti-mitochondrial antibodies (AMAs) recognize mitochondrial antigens and are associated with some diseases involving multiple organs, such as primary biliary cholangitis, Sjögren syndrome, Hashimoto's thyroiditis, systemic sclerosis, interstitial pneumoniae, dilated cardiomyopathy, and tubulointerstitial nephritis. In the current study, we examined the prevalence of AMAs in patients with dilated cardiomyopathy (DCM) and their clinical characteristics. Methods We enrolled 270 patients with DCM. We measured serum AMAs and analyzed the associated factors. Out of the 270 patients, positive AMAs were detected in 3 patients (1.1%; mean age, 68 years old; 2 men). These three patients had a significantly higher prevalence of primary biliary cholangitis and myopathy and levels of alanine alkaline phosphatase than those who were negative for said antibodies. There were no significant differences in the levels of B-type natriuretic peptide, aspartate transaminase, and left ventricular ejection fraction between these groups of patients. During the follow-up period, two of the three patients died due to respiratory failure. The other patient survived but experienced type II respiratory failure. Conclusion The prevalence of AMAs in 270 DCM patients was only 1.1%, and these patients suffered from respiratory failure.

Variant and Specific Forms of Autoimmune Cholestatic Liver Diseases

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

Cardiac involvement in patients with primary biliary cholangitis: A 14-year longitudinal survey-based study

Patients with primary biliary cholangitis (PBC) can have extrahepatic manifestations. However, data about cardiac involvement of PBC is limited. We aimed in this study to analyze the clinical characteristics in patients with PBC complicated with and without cardiac involvement, and the risk factors of cardiac involvement in PBC. PBC patients admitted to Peking Union Medical College Hospital between January 2002 and February 2016 were consecutively enrolled. Structured interview, systemic rheumatologic examination, and laboratory tests were conducted for each patient, and risk factors of cardiac involvement were analyzed by comparing patients with and without cardiac involvement. In total, 580 PBC patients were enrolled, and cardiac involvement was identified in 24 patients (4%), with 11 male (46%) and a mean age of 57±8 year. Cardiomyopathy and arrhythmias were presented in 17 (70.8%) and 21 (87.5%) patients, respectively. Patients with cardiac involvement were more frequently male (46% vs. 11%, P<0.01), complicated with inflammatory myopathy (IM) (58% vs. 1%, P<0.01), and had a longer disease course (median, 72 vs 24 month, P<0.01). Furthermore, concomitant IM was the independent risk factor of cardiac involvement in PBC (OR = 77.333, 95% CI: 23.704–252.294). Cardiac involvement was a rare complication of PBC, which was more frequently observed in male or long-course patients. Importantly, concomitant IM was the strong independent risk factor of cardiac involvement in PBC. Given cardiac involvement is a serious complication, thorough evaluation of cardiac manifestation in high-risk PBC patients is highly recommended.

Recent advances in the diagnosis and treatment of primary biliary cholangitis

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

Pulmonary Manifestations among Patients with Primary Biliary Cirrhosis

Primary biliary cirrhosis (PBC) is a chronic progressive cholestatic liver disease caused by diffuse inflammation, destruction and fibrosis of the intrahepatic bile ducts, ultimately leading to cirrhosis, portal hypertension and liver failure. The pathogenesis of PBC is incompletely understood, but current data suggest roles for genetic susceptibility and environmental factors. PBC is often thought of as an organ-specific autoimmune disease, which mainly targets the liver; however, lung tissue is also a site for autoimmune involvement of PBC. The pulmonary manifestations of PBC include abnormalities in gas transfer and pulmonary function, subclinical alveolitis, interstitial lung disease, granulomatous lung disease, airway disease, pulmonary hypertension, pulmonary hemorrhage and pleural effusion.

Gender differences in autoimmune disease

Autoimmune diseases are a range of diseases in which the immune response to self-antigens results in damage or dysfunction of tissues. Autoimmune diseases can be systemic or can affect specific organs or body systems. For most autoimmune diseases there is a clear sex difference in prevalence, whereby females are generally more frequently affected than males. In this review, we consider gender differences in systemic and organ-specific autoimmune diseases, and we summarize human data that outlines the prevalence of common autoimmune diseases specific to adult males and females in countries commonly surveyed. We discuss possible mechanisms for sex specific differences including gender differences in immune response and organ vulnerability, reproductive capacity including pregnancy, sex hormones, genetic predisposition, parental inheritance, and epigenetics. Evidence demonstrates that gender has a significant influence on the development of autoimmune disease. Thus, considerations of gender should be at the forefront of all studies that attempt to define mechanisms that underpin autoimmune disease.

Recent advances in diagnosis and treatment of primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is a chronic progressive cholestatic autoimmune liver disease characterized by the destruction of small intrahepatic bile ducts and the presence of highly specific serum antimitochondrial antibodies (AMAs). In this article, we will review the clinical, serological and histopathological features of PBC as well as the advances in the diagnosis and differential diagnosis of PBC. In addition, this article systematically describes the advances in the treatment of PBC, and the treatments include ursodeoxycholic acid (UDCA), budesonide, methotrexate (MTX), farnesoid X receptor (FXR) agonists, cyclosporine A, bezafibrate, rituximab, bone marrow-derived mesenchymal stem cell (BM-MSC) transplantation, and liver transplantation. At present, liver transplantation is the only option with known therapeutic benefit for end-stage PBC patients.

Reduced thoracic fluid content in early-stage primary biliary cirrhosis that associates with impaired cardiac inotropy

Primary biliary cirrhosis (PBC) is a chronic liver disease characterized by cholestasis. Recent MRI studies have confirmed the presence of cardiac abnormalities in noncirrhotic PBC patients. However, cardiorespiratory consequences of these abnormalities have not been explored. Thoracic fluid content (TFC) is a noninvasive bioelectrical impedance measure of the electrical conductivity of the chest cavity. We explored TFC and its relationship with cardiac contractility parameters in early-stage PBC patients, compared with chronic liver disease and community controls. TFC was measured in early-stage PBC (noncirrhotic; n = 78), nonalcoholic fatty liver disease (n = 23), and primary sclerosing cholangitis (n = 18) and in a community control population (n = 78). Myocardial contractility was measured as index of contractility, acceleration index, cardiac index, stroke index, left ventricular ejection time, and left ventricular work index. We also measured total arterial compliance and the Heather Index (HI; cardiac inotropy). The PBC group had significantly lower TFC compared with controls and the chronic liver disease groups (P < 0.0001). There was an association between increasing TFC and markers of cardiac function (cardiac index, stroke index, end-diastolic index, index of contractility, and acceleration index), together with indicators of cardiac inotropy and total arterial compliance. Multivariate analysis confirmed that the only parameter that independently associated with TFC was the marker of cardiac inotropy HI (P = 0.037; β 0.5). This study has confirmed that TFC is reduced in those with PBC, that this is specific to PBC, and that it associates independently with markers of cardiac inotropy.

Connective tissue diseases in primary biliary cirrhosis: A population-based cohort study

AIM: To establish the frequency and clinical features of connective tissue diseases (CTDs) in a cohort of Chinese patients with primary biliary cirrhosis (PBC).

METHODS: Three-hundred and twenty-two Chinese PBC patients were screened for the presence of CTD, and the systemic involvement was assessed. The differences in clinical features and laboratory findings between PBC patients with and without CTD were documented. The diversity of incidence of CTDs in PBC of different countries and areas was discussed. For the comparison of normally distributed data, Student’s t test was used, while non-parametric test (Wilcoxon test) for the non-normally distributed data and 2 × 2 χ² or Fisher’s exact tests for the ratio.

RESULTS: One-hundred and fifty (46.6%) PBC patients had one or more CTDs. The most common CTD was Sjögren’s syndrome (SS, 121 cases, 36.2%). There were nine cases of systemic sclerosis (SSc, 2.8%), 12 of systemic lupus erythematosus (SLE, 3.7%), nine of rheumatoid arthritis (RA, 2.8%), and 10 of polymyositis (PM, 3.1%) in this cohort. Compared to patients with PBC only, the PBC + SS patients were more likely to have fever and elevated erythrocyte sedimentation rate (ESR), higher serum immunoglobulin G (IgG) levels and more frequent rheumatoid factor (RF) and interstitial lung disease (ILD) incidences; PBC + SSc patients had higher frequency of ILD; PBC + SLE patients had lower white blood cell (WBC) count, hemoglobin (Hb), platelet count, γ-glutamyl transpeptidase and immunoglobulin M levels, but higher frequency of renal involvement; PBC + RA patients had lower Hb, higher serum IgG, alkaline phosphatase, faster ESR and a higher ratio of RF positivity; PBC + PM patients had higher WBC count and a tendency towards myocardial involvement.

CONCLUSION: Besides the common liver manifestation of PBC, systemic involvement and overlaps with other CTDs are not infrequent in Chinese patients. When overlapping with other CTDs, PBC patients manifested some special clinical and laboratory features which may have effect on the prognosis.

Gastric variceal bleeding uncovering a rare association of CREST syndrome, primary biliary cirrhosis, nodular regenerative hyperplasia and pulmonary hypertension

A 73-year-old woman was admitted after the first upper gastric tract haemorrhage due to gastric variceal bleeding. A CREST syndrome associated with Hashimoto's thyroiditis, Gougerot-Sjögren syndrome, cryoglobulinaemia and complicated with severe pulmonary hypertension was diagnosed. Liver histology found precirrhotic lesions of primary biliary cirrhosis (PBC) and nodular regenerative hyperplasia (NRH). Collagen diseases are often associated with liver test abnormalities and liver disease usually associated with CREST syndrome is PBC. NRH has been found in association with collagen diseases but also with haematological diseases or drugs or with autoimmune diseases, such as PBC. This case shows the association of PBC and NRH with porto pulmonary hypertension in CREST syndrome.

Pulmonary hypertension in China: pulmonary vascular disease: the global perspective

Significant progress has been made in understanding the pathogenesis of pulmonary hypertension (PH) and developing therapeutic approaches for PH in recent years. Most of the currently available data regarding the prevalence, diagnosis, treatment, and prognosis of PH are from American and European populations. Whether these data are also valid in the Chinese population is still controversial. China has a relatively large population of patients with PH for clinical and basic research. However, many medical centers and hospitals in China have limited experience with PH diagnosis and treatment. Given the potential higher prevalence of PH in China than in the United States and European countries, it is critical to develop suitable, effective, and novel therapeutic approaches for Chinese patients. Measures for the detection and prevention of PH need to be put in place urgently for the management of PH in China.