The coexistence of Sjögren's syndrome and primary biliary cirrhosis: a comprehensive review

Clinical and laboratory characteristics of Sjögren's syndrome-associated autoimmune liver disease: a real-world, 10-year retrospective study

OBJECTIVES

To investigate the clinical and laboratory features of Sjögren's syndrome-associated autoimmune liver disease (SS-ALD) patients and identify potential risk and prognostic factors.

METHODS

SS patients with or without ALD, who visited Tongji Hospital between the years 2011 and 2021 and met the 2012 American College of Rheumatology (ACR) classification criteria for Sjögren's syndrome, were retrospectively enrolled. The clinical and laboratory data of the enrolled patients, including autoimmune antibodies, were collected and analyzed with principal component analysis, correlation analysis, LASSO regression, and Cox regression.

RESULTS

A total of 117 SS-ALD patients were confirmed out of 568 SS patients. Compared to SS-non-ALD patients (n = 451), SS-ALD patients exhibited more severe involvement of the hepatic and hematologic systems, albeit with less pronounced typical SS symptoms. Disease activity was higher in SS-ALD patients, as indicated by elevated ESR, CRP, and IL-6 levels, particularly in the SS-overlap subgroup. Furthermore, SS-AIH patients without AIH-specific autoantibody testing or with negative testing results had higher AST and ALT levels than those who were autoantibody-positive. Our predictive model, incorporating IgG, IgM, AST, GGT, ALT, and C4, effectively identified ALD complications in SS patients, achieving an AUC of 0.924. Additionally, a grimmer prognosis was associated with higher baseline AST and ALT levels.

CONCLUSIONS

SS-ALD patients often manifest with an insidious onset and atypical SS symptoms, yet frequently exhibit severe systemic involvement, intense inflammatory and immune responses, and a poor prognosis. To improve the clinical outcomes in SS-ALD patients, regular monitoring, early identification, and active treatment should be applied. Key Points • The study provided a detailed profile of clinical and laboratory features of SS-ALD and SS-non-ALD patients, contributing to a predictive model of ALD complications in SS patients • SS-ALD patients manifested with an insidious onset but exhibited severe systemic involvement, robust inflammatory and immune responses, and poor prognosis • SS-AIH patients without available testing for AIH-specific autoantibodies or with negative results demonstrated worse liver function, thus routine screening for autoimmune liver antibodies is recommended in SS patients • More severe baseline liver function status was associated with poorer therapeutic responses to routine medications, so early detection and timely intervention are essential for SS patients.

Rare renal proximal tubular dysfunctions in primary biliary cholangitis

INTRODUCTION

Renal involvement of primary biliary cholangitis (PBC) usually presents as distal renal tubular acidosis. Proximal tubular (PT) dysfunctions in PBC were rarely reported with unclear clinicopathological characteristics and renal prognosis.

METHODS

We identified 11 cases of PBC with PT dysfunctions (PBC-PT). Their medical document, kidney pathology, and follow-up data were retrospectively reviewed and analyzed.

RESULTS

The 11 PBC-PT patients were mainly middle-aged (57.8 ± 5.2 years) females (81.8%). Most of them were asymptomatic PBC (7, 63.6%) with a high prevalence of elevated serum immunoglobulin M (IgM, 81.8%) and G (IgG, 54.5%) levels. In the kidney, they had a mean estimated glomerular filtration rate (eGFR) level of 46.54 ± 23.03 ml/min/1.73m2, and 81.8% of them had eGFR below 60 ml/min/1.73m2. They showed different degrees of PT dysfunctions, including hyperuricosuria, hypouricemia, normoglycemic glycosuria, generalized aminoaciduria, hyperphosphaturia, and hypophosphatemia. Their kidney pathology showed tubulointerstitial nephritis with lymphoplasmacytic infiltrates, brush border defects, and proximal tubulitis. After glucocorticoids treatment, the PT dysfunctions manifesting as hypophosphatemia, hypouricemia, and renal glycosuria all recovered, and the eGFR levels were improved from 43.24 ± 19.60 ml/min/1.73m2 to 55.02 ± 21.14 ml/min/1.73m2 (p = 0.028), accompanied by significant improvements of serum IgM levels (from 5.97 ± 4.55 g/L to 2.09 ± 1.48 g/L, p = 0.019).

CONCLUSIONS

The PT dysfunctions were rare in PBC patients, and glucocorticoids treatment could benefit the improvements of eGFR and tubular functions.

Prevalence and clinical significance of anti-SSA antibody in the Chinese health screening population

Anti-Sjögren's syndrome type A (anti-SSA) antibodies are non-organ-specific autoantibodies highly prevalent in various autoimmune diseases. This study primarily investigated the prevalence of anti-SSA antibodies in the health screening population. Additionally, we explored the clinical features of the anti-SSA antibody-positive population and evaluated the development of connective tissue diseases (CTD) over the years in individuals with anti-SSA antibodies for whom follow-up was available. A total of, 64 045 individuals without a history of CTD from 2013 to 2022 who visited Peking Union Medical College Hospital for health screening were screened for autoimmune antibodies: 1.7% (1091/64 045) of the Chinese health screening population were positive for anti-SSA antibodies, with a prevalence of 0.9% (290/33 829) in men and 2.7% (801/30 216) in women. Compared with matched autoantibody-negative controls, anti-SSA antibody-positive individuals had higher levels of serological abnormalities, including erythrocyte sedimentation rate (ESR) [10 (6-15) mm/h vs. 7 (4-12) mm/h, P < 0.0001], rheumatoid factor (RF) [7.15 (4.30-16.90) IU/ml vs. 5.00 (3.20-7.90) IU/ml, P < 0.0001], and immunoglobulin G [13.09 (11.20-15.45) g/L vs. 11.34 (9.85-13.18) g/L, P < 0.0001], and lower levels of white blood cells (WBC; 5.49 ± 1.50 × 109/L vs. 5.82 ± 1.49 × 109/L, P < 0.0001). Additionally, they had a higher proportion of coexisting thyroid autoantibodies, including anti-thyroid peroxidase antibodies (TPO-Ab) (17.1% vs. 11.3%, P < 0.0001) and anti-thyroglobulin antibodies (Tg-Ab) (17.8% vs. 11.0%, P < 0.0001). Among the 381 subjects who were anti-SSA positive and followed up for a median of 4.6 years, 146 (38.3%) individuals developed CTD, including 68 (17.8%) cases of primary Sjögren's syndrome (pSS), 10 (2.6%) cases of rheumatoid arthritis (RA), 5 (1.3%) cases of systemic lupus erythematosus (SLE), 4 (1.0%) cases of secondary Sjögren's syndrome (sSS), and 59 (15.5%) cases of undifferentiated connective tissue disease (UCTD). In all, 235 (61.7%) individuals did not develop CTD over a median time of 5.9 (2.9-8.1) years after the earliest autoantibody detection. Elevated ESR (>20 mm/h), RF positivity (>20 IU/ml), and female gender were identified as independent risk factors for CTD among the anti-SSA antibody-positive individuals. Anti-SSA antibodies were found in 17 among approximately 1000 individuals without a history of autoimmune diseases. Anti-SSA antibody-positive individuals are advised to periodically monitor thyroid function. Elevated ESR (>20 mm/h), female gender, and RF positivity may delineate a high-risk cohort for CTDs.

Dissecting causal relationships between primary biliary cholangitis and extrahepatic autoimmune diseases based on Mendelian randomization

As an autoimmune disease, up to 73% of patients with primary biliary cholangitis (PBC) have a combination of extrahepatic autoimmune diseases (EHAIDs); however, the causal relationship between PBC and EHAIDs is unclear. The genome-wide association analyses provided 14 GWAS data for PBC and EHAIDs, and bidirectional, two-sample MR analyses were performed to examine the relationship between PBC and EHAIDs. The analysis using MR provides a strong and meaningful estimation of the bidirectional correlation between PBC and 7 EHAIDs: rheumatoid arthritis, systemic lupus erythematosus, Sjögren's syndrome, systemic sclerosis, autoimmune hypothyroidism, inflammatory bowel disease and ulcerative colitis of its types. In addition, PBC increases the risk of autoimmune thyroid diseases such as autoimmune hyperthyroidism and Graves' disease, as well as multiple sclerosis and psoriasis. Additionally, PBC is identified as a risk factor for Crohn's disease and Celiac disease. Based on genetic evidence, there may be connections between PBC and specific EHAIDs: not all coexisting EHAIDs induce PBC, and vice versa. This underscores the significance of prioritizing PBC in clinical practice. Additionally, if any liver function abnormalities are observed during treatment or with EHAIDs, it is crucial to consider the possibility of comorbid PBC.

Extrahepatic conditions of primary biliary cholangitis: A systematic review and meta-analysis of prevalence and risk

BACKGROUND AND AIM

Many studies reported the prevalence of extrahepatic conditions (EHC) of primary biliary cholangitis (PBC), but the great heterogeneity existed across different studies. Therefore, we conducted the systematic review and meta-analyses to determine EHC prevalence and association with PBC.

METHODS

We searched PUBMED and included observational, cross-sectional and case-controlled studies. A random or fixed effects model was used to estimate the pooled prevalence and odd ratio (OR) as appropriate.

RESULTS

Of 5370 identified publications, 129 publications with 133 studies met the inclusion criteria. Sjögren's syndrome had the highest prevalence (21.4 % vs. 3 % in non-PBC individuals), followed by Raynaud's syndrome (12.3 % vs. 1 %), rheumatoid arthritis-like arthritis (5 % vs. 3 %), systemic sclerosis (3.7 % vs. 0 %) and systemic lupus erythematosus (2 % vs. 0 %). The prevalence of overall thyroid diseases (11.3 %), autoimmune thyroid diseases (9.9 %), osteoporosis (21.1 %), celiac disease (1 %) and chronic bronchitis (4.6 %) was also increased among PBC patients.

CONCLUSION

This is the first exhaustive study on the old theme about EHC of PBC. Given increased prevalence of many EHCs in PBC patients, promptly recognizing these EHCs are of great importance for timely and precise diagnosis of PBC.

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.

A case report of primary biliary cholangitis combined with ankylosing spondylitis

RATIONALE

A chronic autoimmune liver disease known as primary biliary cholangitis (PBC) that selectively destructs small intrahepatic biliary epithelial cells and may result in biliary cirrhosis and eventually liver transplantation or death. PBC is associated with various other extrahepatic autoimmune diseases; however, the combination of PBC with ankylosing spondylitis has been rarely reported in the literature. Here, we reported a case of PBC with ankylosing spondylitis to improve our understanding of such coexistence and provide new ideas for the treatment of such patients.

PATIENT CONCERNS

A 54-year-old man was presented to the Department of Rheumatology because of an abnormal liver function test for 7 years, chest and back pain for 1 year, and low back pain for 2 months.

DIAGNOSES

Primary biliary cholangitis, ankylosing spondylitis, and old pulmonary tuberculosis.

INTERVENTIONS

The patient refused to use nonsteroidal anti-inflammatory drugs, conventional synthetic disease-modifying antirheumatic drugs, and biologic disease-modifying antirheumatic drugs; thus, he was treated with methylenediphosphonate (99Tc-MDP) and ursodeoxycholic acid (UDCA).

OUTCOMES

The patient achieved remission with UDCA and 99Tc-MDP therapy.

LESSONS

In the treatment of PBC combined with other disorders, the characteristics of different diseases should be considered. The patient reported herein was treated with 99Tc-MDP and UDCA, and his condition improved; thus, we consider 99Tc-MDP to be an effective treatment. Furthermore, in line with the current understanding of the pathogenesis of PBC and ankylosing spondylitis, we hypothesize that interleukin-17 inhibitor is an effective treatment for such patients.

Laboratory risk factors for coexistent primary biliary cholangitis in patients with Sjögren's syndrome: a retrospective study

BACKGROUND

Limited research exists on the laboratory characteristics of coexistent primary biliary cholangitis (PBC) and Sjögren's syndrome (SS). This study aimed to investigate the laboratory risk factors for the coexistence of PBC in patients with SS.

METHODS

Eighty-two patients with coexistent SS and PBC (median age 52.50 years) and 82 age- and sex-matched SS controls were retrospectively enrolled between July 2015 and July 2021. The clinical and laboratory characteristics of the two groups were compared. Laboratory risk factors for the coexistence of PBC in patients with SS were analyzed using logistic regression analysis.

RESULTS

Both groups had a similar prevalence of hypertension, diabetes, thyroid disease, and interstitial lung disease. Compared with the SS group, patients in the SS + PBC group had higher levels of liver enzymes, immunoglobulins M (IgM), G2, and G3 (P < 0.05). The percentage of patients with an antinuclear antibody (ANA) titre > 1:10000 in the SS + PBC group was 56.1%, higher than that in the SS group (19.5%, P < 0.05). Additionally, cytoplasmic, centromeric, and nuclear membranous patterns of ANA and positive anti-centromere antibody (ACA) were observed more frequently in the SS + PBC group (P < 0.05). Logistic regression analysis showed that elevated IgM levels, high ANA titre, cytoplasmic pattern, and ACA were independent risk factors for PBC coexistence in SS.

CONCLUSIONS

In addition to established risk factors, elevated IgM levels, positive ACA, and high ANA titre with cytoplasmic pattern provide clues to clinicians for the early screening and diagnosis of PBC in patients with SS.

Liver Fibrosis in Primary Sjögren’s Syndrome

Background

Primary Sjögren syndrome (pSS) is a systemic autoimmune epithelitis, potentially affecting salivary epithelium, biliary epithelium, and hepatocytes. Common immunological mechanisms might cause clinically silent liver inflammation, and combined with non-alcoholic fatty liver disease (NAFLD), liver fibrosis (LF) may occur. No studies have explored the occurrence of LF in the context of NAFLD among pSS patients.

Methods

Consecutive pSS patients from the rheumatology outpatient clinic of the Department of Pathophysiology and individuals evaluated in the hepatology outpatient clinic for possible NAFLD serving as comparators underwent transient elastography (TE) to assess LF and liver steatosis (LS). All participants had no overt chronic liver disease. Clinical, demographic, and laboratory data were collected from all participants at the time of TE.

Results

Fifty-two pSS patients and 198 comparators were included in the study. The median age (range) of pSS and comparators was 62.5 (30–81) and 55 (19–86) years, respectively. Both groups had similar prevalence regarding type 2 diabetes mellitus, hyperlipidemia, and similar body mass index (BMI). Patients with pSS had less frequently high LS (S2, S3) (27% vs. 62%, p < 0.001) and significant LF (F2–4) [2 (3.8%) vs. 34 (17.2%), p = 0.014] than comparators. Univariable analysis showed that advanced LF was significantly associated with older age, higher LS, greater BMI, and disease status (comparators than pSS); of these, only age was identified as an independent LF risk factor in the multivariable logistic regression analysis.

Conclusion

Liver fibrosis among pSS patients is most likely not attributed to the disease per se.

Evaluation of Inhibitory Antibodies against the Muscarinic Acetylcholine Receptor Type 3 in Patients with Primary Biliary Cholangitis and Primary Sclerosing Cholangitis

Background: Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) constitute rare chronic inflammatory biliary diseases which likely comprise genetic, environmental and autoimmune factors. Specific inhibitory (auto-) antibodies against the muscarinic acetylcholine receptor type 3 (mAChR3 auto-ab) may contribute to the pathogenesis of chronic biliary inflammation by modulating mAChR3− mediated signaling. Aims: The aim of this study was to analyze the prevalence and relevance of inhibitory mAChR3 auto-ab (mAChR3inh+ auto-ab) in a large cohort of PBC patients from two independent tertiary centers in Berlin and Leipzig in comparison to a large PSC cohort. Baseline parameters and response rates to standard treatment with ursodeoxycholic acid (UDCA) were characterized with respect to the individual mAChR3 auto-ab status. Methods: In total, the study population comprised 437 PBC patients, 187 PSC patients and 80 healthy controls. Clinical and laboratory baseline characteristics were retrieved from medical records. The response to ursodeoxycholic acid (UDCA) therapy after 12 months of treatment was available in 176 PBC and 45 PSC patients. Results: The prevalence of mAChR3inh+ auto-ab was significantly higher among PBC patients (11.2%, 49/437; p = 0.008 vs. healthy controls) and PSC patients (33.6%, 63/187; p < 0.0001 vs. healthy controls) compared to healthy controls (2.5%, 2/80), respectively. PBC patients with mAChR3inh+ auto-ab exhibited significantly higher levels of alkaline phosphatase (ALP) and bilirubin, which constitute established parameters for PBC risk stratification. Moreover, mAChR3inh+ PBC patients tended to show decreased response rates to UDCA therapy compared to PBC patients without mAChR3inh+ auto-ab (mAChR3− PBC). In contrast, PSC patients with mAChR3inh+ auto-ab showed no significant differences in laboratory findings compared to mAChR3 auto-ab negative (mAChR3−) PSC patients. Conclusion: MAChR3inh+ auto-ab might be involved in the pathogenesis and treatment response of chronic biliary inflammation in patients with PBC but not in patients with PSC.

Toxoplasma gondii infection as a potential risk for chronic liver diseases: A systematic review and meta-analysis

Toxoplasma gondii, the etiological agent of toxoplasmosis, can cause serious public health problems. Although Toxoplasma gondii tends more to neurotropic and ocular organs, some existing evidence suggest that this disease might induce serious pathological effects on liver. Hence, this study aimed to evaluate the relationship between chronic liver diseases and toxoplasmosis. Meanwhile, it attempted to assess whether patients with toxoplasmosis are susceptible to chronic liver diseases. To achieve this aim, the published studies related to the subject were systematically searched in five major electronic databases between the January 1, 1950 and October 1, 2019. The meta-analysis was carried out using the StatsDirect statistical software and a p-value less than 0.05 was considered significant for any test. Out of 691 identified studies, 10 studies met our inclusion criteria and entered this systematic review. The pooled prevalence rates of Toxoplasma gondii in patients with liver diseases (35.97%; 95% CI: 28.38-43.93) were higher than those in the control group (18.24%; 95% CI: 13.85-23.09). The meta-analysis indicated that the common Odd Ratio by a random effect model was 2.7 (95% CI: 2.30-3.24), revealing a significant association between chronic liver diseases and anti-Toxoplasma IgG antibody. The results of this systematic review confirmed the positive connection between toxoplasmosis and chronic liver diseases. Nonetheless, more studies are needed to clarify the detailed association between these diseases.

[Analysis of clinical features and prognosis in patients with primary Sjögren's syndrome and autoimmune liver disease]

OBJECTIVE

To analyze the clinical features and prognosis in patients with primary Sjögren's syndrome (pSS) and autoimmune liver diseases (ALD).

METHODS

A retrospective analysis of clinical manifestation and prognosis was performed in patients with ALD or without ALD during the three years (February 2014 to December 2017).

RESULTS

Totally, 203 patients with pSS were included in this study, 68 patients had ALD (31 patients with autoimmune hepatitis, 37 patients with primary biliary cholangitis), while 135 patients did not have ALD. There were no differences between the two groups regarding age, gender, clinical manifestations, such as dry mouth, dry eyes, pain, fatigue, lymphadenopathy, glandular swelling, cutaneous involvement, lung involvement, and renal involvement, and the incidence rate of other autoimmune diseases, such as autoimmune thyroid disease, rheumatoid arthritis, and vasculitis. There were also no differences in the titer of antinuclear antibody (ANA), the positive rates of anti-Sjögren's syndrome A antibody (SSA), SSA52, and anti-Sjögren's syndrome B antibody (SSB), and at the levels of erythrocyte sedimentation rate and C-reactive protein between the two groups. Most importantly, the pSS patients with ALD had a shorter disease course, a higher positive rate of anti-mitochondrial M2 antibody (AMA-M2) and anti-centromere antibody, a higher level of IgG and IgM, a lower level of complement 3, and a decreased number of blood cells. They also had a higher level of liver related serum index, such as alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, alkaline phosphatase and total bilirubin, direct bilirubin, indirect bilirubin, a higher incidence rate of liver cirrhosis, an increased death incident (the mortality was 13.24% in the pSS patients with ALD, while 2.96% in the controls, P=0.013), and a worse prognosis. Binary Logistic regression analysis revealed that liver cirrhosis, the EULAR Sjögren's syndrome disease activity index (ESSDAI) scores and the level of total bilirubin were the prognostic factors of mortality in the pSS patients with ALD. The survival curve was estimated by the Kaplan-Meier method. It demonstrated that the pSS patients with ALD had a lower survival rate when compared with the controls.

CONCLUSION

The patients with both pSS and ALD will suffer from a more severe disease and a higher death incident. We should pay more attention to these patients and provide a better symptomatic treatment for them during clinical practice.

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

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

Immunological abnormalities in patients with primary biliary cholangitis

Primary biliary cholangitis (PBC), an autoimmune liver disease occurring predominantly in women, is characterized by high titers of serum anti-mitochondrial antibodies (AMAs) and progressive intrahepatic cholestasis. The immune system plays a critical role in PBC pathogenesis and a variety of immune cell subsets have been shown to infiltrate the portal tract areas of patients with PBC. Amongst the participating immune cells, CD4 T cells are important cytokine-producing cells that foster an inflammatory microenvironment. Specifically, these cells orchestrate activation of other immune cells, including autoreactive effector CD8 T cells that cause biliary epithelial cell (BEC) injury and B cells that produce large quantities of AMAs. Meanwhile, other immune cells, including dendritic cells (DCs), natural killer (NK) cells, NKT cells, monocytes, and macrophages are also important in PBC pathogenesis. Activation of these cells initiates and perpetuates bile duct damage in PBC patients, leading to intrahepatic cholestasis, hepatic damage, liver fibrosis, and eventually cirrhosis or even liver failure. Taken together, the body of accumulated clinical and experimental evidence has enhanced our understanding of the immunopathogenesis of PBC and suggests that immunotherapy may be a promising treatment option. Herein, we summarize current knowledge regarding immunological abnormalities of PBC patients, with emphasis on underlying pathogenic mechanisms. The differential immune response which occurs over decades of disease activity suggests that different therapies may be needed at different stages of disease.

The genetics of primary biliary cholangitis

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

Tissue-Resident Memory CD8+ T Cells Acting as Mediators of Salivary Gland Damage in a Murine Model of Sjögren's Syndrome

OBJECTIVE

Although a role for CD4+ T cells in the pathogenesis of Sjögren's syndrome (SS) has been documented, the pathogenic significance of CD8+ T cells is unclear. The aim of this study was to investigate the role of CD8+ T cells in the development of SS.

METHODS

Flow cytometry and immunofluorescence analyses were utilized to detect T cell infiltration within the labial salivary glands of patients with primary SS. In parallel, p40^-/- CD25^-/- mice were used as a murine model of SS. In addition, mice with genetic knockout of CD4, CD8a, or interferon-γ (IFNγ) were crossed with p40^-/- CD25^-/- mice to study the pathogenic significance of specific lineage subpopulations, including functional salivary gland tests as well as histopathologic and serologic data. A CD8+ T cell-specific depletion antibody was used in this murine SS model to evaluate its potential as a therapeutic strategy.

RESULTS

CD8+ T cells with a tissue-resident memory phenotype outnumbered CD4+ T cells in the labial salivary glands of patients with SS, and were primarily colocalized with salivary duct epithelial cells and acinar cells. Furthermore, infiltrating CD8+ T cells with a CD69+CD103+/- tissue-resident phenotype and with a significant elevation of IFNγ production were dominant in the submandibular glands of mice in this murine SS model. CD8a knockout abrogated the development of SS in these mice. Knockout of IFNγ decreased CD8+ T cell infiltration and gland destruction. More importantly, depletion of CD8+ T cells fully protected mice against the pathologic manifestations of SS, even after the onset of disease.

CONCLUSION

These data reveal the pathogenic significance of CD8+ T cells in the development and progression of SS in the salivary glands. Treatment directed against CD8+ T cells may be a rational therapy for the management of SS in human subjects.

Cutaneous and Mucosal Manifestations of Sjögren's Syndrome

Sjögren's syndrome is currently considered an "autoimmune epithelitis," as exocrine glands, especially salivary and lacrimal, are progressively destructed by an immune-mediated process associated with specific serum autoantibodies and local lymphocyte infiltrate. Xerostomia remains a key complain in patients with Sjögren's syndrome but should be evaluated also for other causes such as xerogenic medications, followed by radiation and chemotherapy for head and neck cancers, hormone disorders, infections, or other connective tissue diseases. Further, xerophtalmia (also known as dry eye) frequently associated with keratoconjunctivitis sicca cumulatively affects approximately 10-30% of the general population with increasing incidence with age and is more frequently secondary to non-autoimmune diseases. On the other hand, numerous patients with Sjögren's syndrome manifest signs of systemic dryness involving the nose, the trachea, the vagina, and the skin, suggesting that other glands are also affected beyond the exocrine epithelia. Skin involvement in Sjögren's syndrome is relatively common, and various manifestations may be present, in particular xeroderma, eyelid dermatitis, annular erythema, and cutaneous vasculitis. Additional skin non-vasculitic manifestations include livedo reticularis which may occur in the absence of vasculitis, and localized nodular cutaneous amyloidosis possibly representing lymphoproliferative diseases related to Sjögren's syndrome. The treatment of skin and mucosal manifestations in Sjögren's syndrome is similar regardless of the cause, starting from patient education to avoid alcohol and tobacco smoking and to pursue dental hygiene. In conclusion, a strict collaboration between the dermatologist and the rheumatologist is essential in the adequate management of Sjögren's syndrome skin and mucosal manifestations.

Gastrointestinal and Hepatic Disease in Rheumatoid Arthritis

Gastrointestinal (GI) manifestations of rheumatoid arthritis (RA) are rare, but can be impactful for patients. Some GI processes are directly related to RA, whereas others may be sequelae of treatment or caused by concomitant autoimmune diseases. This article discusses the role of the GI tract in RA pathogenesis; the presentation, epidemiology, and diagnosis of RA-related GI manifestations; concomitant GI autoimmune diseases that may affect those with RA; and GI side effects of RA treatment. The importance of appropriately considering conditions unrelated to RA in the differential diagnosis when evaluating new GI symptoms in patients with RA is noted.

Hepatobiliary involvement in systemic sclerosis and the cutaneous subsets: Characteristics and survival of patients from the Spanish RESCLE Registry

OBJECTIVE

To assess the prevalence and causes of hepatobiliary involvement (HBI) in systemic sclerosis (SSc), to investigate the clinical characteristics and prognosis of SSc patients with HBI (SSc-HBI) and without HBI (SSc-non-HBI), and to compare both groups according to the cutaneous SSc subsets.

METHODS

In all, 1572 SSc patients were collected in the RESCLE registry up to January 2015, and all hepatobiliary disturbances were recorded. We investigated the HBI-related characteristics and survival from the entire SSc cohort and according to the following cutaneous subsets: diffuse cutaneous SSc (dcSSc), limited cutaneous SSc (lcSSc), and SSc sine scleroderma (ssSSc).

RESULTS

Out of 1572, 118 (7.5%) patients had HBI. Primary biliary cholangitis (PBC) was largely the main cause (n = 67, 4.3%), followed by autoimmune hepatitis (n = 19, 1.2%), and anti-mitochondrial negative PBC (n = 6, 0.4%). Other causes of HBI were as follows: secondary liver diseases (n = 11, 0.7%), SSc-related HBI (n = 7, 0.4%), nodular regenerative hyperplasia (n = 3, 0.2%), liver cirrhosis (n = 3, 0.2%), and HBI of unknown origin (n = 2, 0.1%). In multivariate analysis, HBI was independently associated to lesser risk of dcSSc (5.1% vs. 24.4%), and higher frequency of calcinosis (26% vs. 18%), left ventricular diastolic dysfunction (46% vs. 27%), sicca syndrome (51% vs. 29%), and anti-centromere antibodies (ACA, 73% vs. 44%). According to the cutaneous subsets, HBI was associated (1) in lcSSc, to longer time from SSc onset to diagnosis (10.8 ± 12.5 vs. 7.2 ± 9.3 years), sicca syndrome (54% vs. 33%), and ACA (80% vs. 56%); (2) in ssSSc, to sicca syndrome (44% vs. 19%), and (3) in dcSSc, no associations were found. HBI was the cause of death in 2.3% patients but the cumulative survival according to the presence or absence of HBI showed no differences.

CONCLUSIONS

HBI prevalence in SSc is 7.5% and dcSSc is the least involved subset. PBC is the main cause of HBI. Patients with SSc-HBI exhibited specific clinical and immunologic profile. Survival is similar for SSc patients with HBI.

Chronic Autoimmune Epithelitis in Sjögren's Syndrome and Primary Biliary Cholangitis: A Comprehensive Review

Within the spectrum of autoimmune diseases, Sjögren's syndrome and primary biliary cholangitis are exemplary and can be coined as chronic epithelitis based on their frequent coexistence in clinical practice and the highly specific immune-mediated injury of the small bile ducts and the exocrine glands. The pathogenic mechanisms underlying the diseases are similar, with apoptosis being the key element leading to organ-specific immune-mediated injury directed against the small bile ducts and salivary gland epithelia, respectively along with similar epidemiological features, such as female predominance and the age of onset in the fifth decade of life. Indeed, novel insights into the pathogenesis of the diseases have been obtained in recent years, including a better definition of the role of B and T cells, particularly Th17 cells, and the mechanisms of autoantibody-mediated tissue injury, with anti-mitochondrial antibodies and SS-A/SS-B being identified as specific for primary biliary cholangitis and Sjögren's syndrome, respectively. These findings have opened the possibility to new targeted therapies, but most clinical needs remain unmet, particularly from a therapeutic standpoint where options diverge, with bile acids being the predominant treatment strategy in primary biliary cholangitis and immunomodulators being used to treat Sjögren's syndrome. Here we provide a comprehensive review of the most recent findings on the pathogenesis, clinical manifestations and therapeutic options for Sjögren's syndrome and primary biliary cholangitis, respectively, while stressing the common traits between these conditions. Our cumulative hypothesis is that similarities outnumber differences and that this may prove advantageous towards a better management of patients.

Analysis of Clinical Characteristics of Immune-Related Dry Eye

AIM

To discuss the clinical characteristics of immune-related dry eye.

METHODS

Simple dry eye (SDE) group: we selected 224 patients of simple dry eye with no systemic lesions. Immune-related dry eye (IRDE) group: we selected 207 patients of dry eye complicated with immune system diseases, including 70 cases of Sjögren's syndrome (SS), 72 cases of systemic lupus erythematosus (SLE), and 65 cases of rheumatoid arthritis (RA). The classification of all patients was performed. The difference between the two groups was compared, including age, gender, ocular surface fluorescein staining and inflammatory reaction, tear breakup time (TBUT), Shirmer I test, confocal microscopy scan, and dry eye grading.

RESULTS

Compared with the SDE group, the patients of IRDE group were younger (P < 0.05). The female patients were significantly more than the male ones (P < 0.05). Corneal staining counts and ocular surface inflammation were significantly increased (P < 0.05). TBUT and Shirmer I test shortened significantly (P < 0.05). Corneal nerve fibers were less, and the number of local lymphocyte was significant increased. The number of dry eye patients in the moderate or above IRDE group was significantly increased (P < 0.05).

CONCLUSIONS

The dry eye symptom and sign and ocular surface inflammation of IRDE were significantly more severe than those of the SDE.

The Immune Response and the Pathogenesis of Idiopathic Inflammatory Myositis: a Critical Review

The pathogenesis of idiopathic inflammatory myositis (IIMs, including polymyositis and dermatomyositis) remains largely enigmatic, despite advances in the study of the role played by innate immunity, adaptive immunity, genetic predisposition, and environmental factors in an orchestrated response. Several factors are involved in the inflammatory state that characterizes the different forms of IIMs which share features and mechanisms but are clearly different with respect to the involved sites and characteristics of the inflammation. Cellular and non-cellular mechanisms of both the immune and non-immune systems have been identified as key regulators of inflammation in polymyositis/dermatomyositis, particularly at different stages of disease, leading to the fibrotic state that characterizes the end stage. Among these, a special role is played by an interferon signature and complement cascade with different mechanisms in polymyositis and dermatomyositis; these differences can be identified also histologically in muscle biopsies. Numerous cellular components of the adaptive and innate immune response are present in the site of tissue inflammation, and the complexity of idiopathic inflammatory myositis is further supported by the involvement of non-immune mechanisms such as hypoxia and autophagy. The aim of this comprehensive review is to describe the major pathogenic mechanisms involved in the onset of idiopathic inflammatory myositis and to report on the major working hypothesis with therapeutic implications.

Proposed therapies in primary biliary cholangitis

Primary biliary cholangitis (PBC), previously known as primary biliary cirrhosis, is a model autoimmune disease with chronic cholestasis characterized by the hallmark of anti-mitochondrial antibodies and treated with ursodeoxycholic acid (UDCA). However, approximately 20-40% of patients incompletely respond to UDCA and have an increased risk of disease progression. Although there have been significant advances in the immunobiology of PBC, these have yet to be translated into newer therapeutic modalities. Current approaches to controlling the immune response include broad immunosuppression with corticosteroids as well as targeted therapies directed against T and B cells. In contrast, ameliorating cholestasis is the focus of other therapies in development, including obeticholic acid. In this article the authors will discuss ongoing clinical trials and, in particular, the rationale for choosing agents that may effectively target the aberrant immune response.

The Natural History and Prognosis of Primary Biliary Cirrhosis with Clinical Features of Autoimmune Hepatitis

Although a variant of primary biliary cirrhosis (PBC) characterized by features of autoimmune hepatitis (AIH) has been recognized for many years, few studies with ample numbers of patients have focused on its natural history. This study aimed to clarify the natural history, prognosis, and response to therapy in a cohort of patients with PBC with AIH features. We retrospectively analyzed 277 PBC patients without AIH features and 46 PBC patients with AIH features seen between September 2004 and April 2014. The 5-year adverse outcome-free survival of PBC patients with AIH features was 58% compared to 81% in PBC patients without AIH features. Multivariate analysis in the patients with AIH features indicated that total bilirubin ≥ 2.70× the upper limit of normal predicted a poor prognosis (p = 0.008, relative risk 8.39, 95% confidence interval (CI) 1.73, 40.73). Combination therapy with ursodeoxycholic acid (UDCA) and immunosuppression provided better short-term responses in PBC patients with AIH features, defined by multiple criteria. Higher aspartate aminotransferase (AST) level at accession suggested better prognosis for PBC patients with AIH features while worse prognosis for PBC patients without AIH features. PBC patients with AIH features differ from those without AIH features in terms of natural history, prognostic indicators, and response to therapy.

Primary rectal mucosa-associated lymphoid tissue lymphoma in a patient with previously identified primary biliary cirrhosis and secondary Sjögren's syndrome

An 83-year-old female began treatment with prednisolone and ursodeoxycholic acid at 62 years of age, following a diagnosis of primary biliary cirrhosis (PBC) and secondary Sjögren’s syndrome (SjS). With persisting bloody stools, the patient underwent colonoscopy at 83 years of age. Histopathological evaluation revealed mucosa-associated lymphoid tissue (MALT) lymphoma. The elevated rectal lesion resolved with rituximab treatment. We report this case because although patients with SjS are at increased risk of malignant lymphoma, primary rectal MALT lymphoma is very uncommon in association with PBC and secondary SjS.

Unmet challenges in immune-mediated hepatobiliary diseases

It is ironic that the liver, which serves a critical function in immune tolerance, itself becomes the victim of an autoimmune attack. Indeed, liver autoimmunity and the autoimmune diseases associated with both innate and adaptive responses to hepatocytes and/or cholangiocytes are models of human autoimmunity. For example, in primary biliary cirrhosis, there exists a well-defined and characteristic autoantibody and considerable homogeneity between patients. In autoimmune hepatitis, there are clinical characteristics that allow a rigorous subset definition and well-defined inflammatory infiltrates. In both cases, there are defects in a variety of immune pathways and including regulatory cells. In primary sclerosing cholangitis, with its characteristic overlap with inflammatory bowel disease, there are unique defects in innate immunity and particular important contribution of lymphoid homing to disease pathogenesis. In these diseases, as with other human autoimmune processes, there is the critical understanding that pathogenesis requires a genetic background, but is determined by environmental features, and indeed the concordance of these diseases in identical twins highlights the stochastic nature of immunopathology. Unfortunately, despite major advances in basic immunology and in immunopathology in these diseases, there remains a major void in therapy. The newer biologics that are so widely used in rheumatology, neurology, and gastroenterology have not yet seen success in autoimmune liver disease. Future efforts will depend on more rigorous molecular biology and systems analysis in order for successful application to be made to patients.