Rheumatologic Diseases and the Liver

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.

Identifying the genetic association between systemic lupus erythematosus and the risk of autoimmune liver diseases

BACKGROUND

Previous studies on the relationship between systemic lupus erythematosus (SLE) and autoimmune liver diseases (AILDs) are inconclusive. Therefore, we employed Mendelian randomization (MR) to explore the causal associations between SLE and AILDs.

METHODS

A two-sample MR analysis was performed using summary-level statistics sourced from genome-wide association study (GWAS) datasets. Inverse-variance weighting (IVW), MR‒Egger, and weighted median (WM) were further supported by several sensitivity analyses.

RESULTS

We detected causal genetic associations between SLE and primary biliary cholangitis (PBC) (odds ratio (OR) = 1.31, 95% CI = 1.15-1.51, P < 0.01; adjusted OR = 1.63, 95% CI = 1.39-1.90, P < 0.01) and between SLE and primary sclerosing cholangitis (PSC) (OR = 1.09, 95% CI = 1.01-1.08, P = 0.03; adjusted OR = 1.10, 95% CI = 1.00-1.21, P = 0.04). No causal association was found between SLE and autoimmune hepatitis.

CONCLUSIONS

We are the first to use MR analysis to explore the causal relationships between SLE and various AILDs, revealing an increased risk of PBC and PSC in individuals with SLE.

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.

Autoimmune Hepatitis: Epidemiology, Subtypes, and Presentation

Autoimmune hepatitis (AIH) is a chronic immunologic disorder in which the immune system targets the liver. The disease has a genetic basis and this accounts for the epidemiologic variation observed in serologic testing and clinical presentation across different populations. The incidence of AIH increases with age into the 70s and seems to be increasing in prevalence. Most patients test positive for antinuclear antibody, ASMA, or anti-LKM but about 20% of patients do not have these serologic markers. At clinical presentation, patients may be asymptomatic, symptomatic, have acute liver failure, or decompensated cirrhosis.

The correlation between red cell distribution width to albumin ratio and all-cause mortality in critically ill patients with rheumatic diseases: a population-based retrospective study

Background

Patients with rheumatic diseases have an increased likelihood of being admitted to the intensive care unit (ICU), highlighting the importance of promptly identifying high-risk individuals to enhance prognosis. This study aimed to assess the correlation of red blood cell distribution width to albumin ratio (RAR) with the 90-days and 360-days survival rates among critically ill rheumatic patients.

Methods

Adult rheumatic patients admitted to the ICU from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database were included. The participants were categorized into two groups, survivors (n = 436) and non-survivors (n = 192), based on their 90-days survival outcome. The population was further classified into tertiles using RAR values, with RAR < 4.63 (n = 208), 4.63-6.07 (n = 211), and > 6.07 (n = 209). Kaplan-Meier curves were utilized to evaluate the cumulative survival rates at 90-days and 360-days. The association between RAR and mortality was assessed using restricted cubic splines (RCS) and multivariate Cox regression analysis. Additional subgroup analyses and sensitivity analyses were conducted to further explore the findings. Receiver operating characteristic (ROC) curves were generated to evaluate the predictive performance of RAR.

Results

This study involved 628 critically ill patients with rheumatic diseases, and they had an all-cause mortality of 30.57% at 90-days and 38.69% at 360-days. Kaplan-Meier analysis showed a gradual decrease in both 90-days and 360-days cumulative survival with increasing RAR (χ2 = 24.400, p < 0.001; χ2 = 35.360, p < 0.001). RCS revealed that RAR was linearly related to 90-days and 360-days all-cause mortality risk for critically ill patients with rheumatic diseases (χ2 = 4.360, p = 0.225; χ2 = 1.900, p = 0.594). Cox regression analysis indicated that elevated RAR (> 6.07) was significantly correlated with mortality. The ROC curves demonstrated that an optimal cut-off value of RAR for predicting 90-days mortality was determined to be 5.453, yielding a sensitivity of 61.5% and specificity of 60.3%.

Conclusion

Elevated RAR (> 6.07) was associated with all-cause mortality at 90-days and 360-days among critically ill patients with rheumatic diseases, serving as an independent risk factor for unfavorable prognosis.

Hepatorenal pathologies in TNF-transgenic mouse model of rheumatoid arthritis are alleviated by anti-TNF treatment

OBJECTIVE

To examine and quantify liver and kidney lesions and their response to anti-tumor necrosis factor (TNF) therapy in a TNF-Tg mouse model of rheumatoid arthritis (RA).

METHODS

Female TNF-Tg (Tg3647) mice were used as the animal model for chronic RA. Ultrasound, immunofluorescence, histological staining, serology tests, and real-time RT-PCR were used to examine the pathological changes in the liver and kidney.

RESULTS

TNF-Tg mice showed a significant decrease in the body weight and a dramatic increase in the volumes of the gallbladder, knee cavity, and popliteal lymph nodes. The liver and kidneys of TNF-Tg mice showed increased chronic inflammation and accumulation of immune cells and fibrosis, compared to wild-type (WT) mice. Moreover, upregulation of inflammatory factors and impaired normal function were observed in the liver and kidneys of TNF-Tg mice. Inflammatory infiltration and fibrosis of the liver and kidneys of female TNF-Tg mice were improved after anti-TNF treatment, and better treatment effects were achieved at 4.5-month-old mice when they were received 8 weeks of intervention.

CONCLUSIONS

We found that TNF drives the development of liver and kidney pathology in female TNF-Tg mice and that there are limitations to the loss of utility of anti-TNF for the prolonged treatment of RA-associated hepatic and renal injury. This study provides a reliable and clinically relevant animal model for further studies exploring the molecular mechanisms and drug discovery for hepatorenal pathologies in RA.

Genetic link between rheumatoid arthritis and autoimmune liver diseases: A two-sample Mendelian randomization study

BACKGROUND

An association between rheumatoid arthritis (RA) and autoimmune liver diseases (AILDs) was found in observational studies. However, neither the direction nor the cause-effect chain was clear. This study aimed to assess the causal associations between AILDs and RA.

METHODS

We performed a two-sample Mendelian randomization (MR) analysis. Following a strict assessment, genome-wide association study (GWAS) datasets were used to select potential candidate single-nucleotide polymorphisms. The inverse-variance weighted (IVW) was used as the primary analysis approach, supplemented with four sensitive analysis methods applied to assess the robustness of the results.

RESULTS

We discovered that a genetically increased primary biliary cholangitis (PBC) risk had a positive causal effect on RA (IVW OR=1.149, 95% CI=1.063-1.241, P<0.001). According to the MR-Egger regression, horizontal pleiotropy was unlikely to impact causality (intercept = -0.028, P = 0.263). Using the leave-one-out strategy, sensitivity studies revealed that the MR analysis results were robust and reliable. Genetically determined primary sclerosing cholangitis (PSC) was not linked with the risk of RA (IVW OR=1.071, 95%CI=0.984-1.166, P = 0.111). The results of the MR analysis were further validated by sensitivity analyses utilizing the leave-one-out approach. In the other direction, there was no causal relationship between RA and PBC (OR=1.132, 95% CI=0.881-1.454, P = 0.333) or PSC (OR=1.067, 95% CI=0.891-1.279, P = 0.088).

CONCLUSIONS

Using a two-sample MR analysis, we investigated the relationship between AILDs and RA and revealed first that PBC increases the risk of RA. Large-scale cross-disease GWAS are required to further illuminate the genomic landscape of AILDs and RA.

Case Report: Interventional therapy for portal venous stenosis caused by systemic vasculitis

Systemic vasculitis are multisystem blood vessel disorders. However, Portal venous involvement is extremely rare, which represents a diagnostic and therapeutic challenge due to the heterogeneous nature, a lack of diagnostic criteria and limited effective therapy of vasculitis. We have reported a 48-year-old woman who was previously diagnosed with systemic vasculitis and was treated with prednisone, presented with gastrointestinal (GI) bleeding on admission. Further abdominal contrast-enhanced computed tomography (CT) with three-dimensional reconstruction suggested atrophic left hepatic lobe, enlarged spleen, and severe stenosis of main portal vein. Liver biopsy showed no evidence of fibrosis/cirrhosis. To prevent rebleeding, portal venous angioplasty by balloon dilation with collateral varices embolization was performed, and the GI hemorrhage was resolved completely. However, refractory ascites presented 8 months postoperatively. Abdominal CT angiography confirmed the recurrence of portal venous stenosis. Portal venous angioplasty by stent implantation was then performed to treat the portal hypertension (PHT)-related complications. After the intervention, the patient received anticoagulation therapy and continued immunosuppressive therapy. During the 5-year follow-up, the patient did not experience any onset of GI bleeding or ascites. Therefore, portal venous angioplasty with stent placement could be an effective treatment to prevent PHT-related complications when immunosuppression therapy failed.

Autoimmune liver diseases in systemic rheumatic diseases

Systemic rheumatic diseases (SRDs) are chronic, inflammatory, autoimmune disorders with the presence of autoantibodies that may affect any organ or system. Liver dysfunction in SRDs can be associated with prescribed drugs, viral hepatitis, alternative hepatic comorbidities and coexisting autoimmune liver diseases (AILDs), requiring an exclusion of secondary conditions before considering liver involvement. The patterns of overlap diseases depend predominantly on genetic determinants with common susceptible loci widely distributing in both disorders. In AILDs, it is important to identify the overlapping SRDs at an early stage since such a coexistence may influence the disease course and prognosis. Commonly co-occurring SRDs in AILDs are Sjögren syndrome (SS), rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE) in autoimmune hepatitis (AIH), and SS, RA or systemic sclerosis in primary biliary cholangitis. Owing to different disease complications and therapies, it is imperative to differentiate between SLE liver involvement and SLE-AIH overlap disease. Therapeutic options can be personalized to control coexisting conditions of liver autoimmunity and rheumatic manifestations in AILD-SRD overlap diseases. The collaboration between hepatologists and rheumatologists can lead to significant advances in managing such a complex scenario. In this review, we provide a comprehensive overview on coexisting AILDs in different SRDs and the therapeutic approach in managing these overlap diseases.

Non-Alcoholic Fatty Liver Disease (NAFLD) in Patients with Psoriasis: A Review of the Hepatic Effects of Systemic Therapies

There is increasing interest in the association between psoriasis and non-alcoholic fatty liver disease (NAFLD), which is a prevalent liver disease characterized by excessive fat storage and inflammation that can progress to fibrosis and cancer. Patients with psoriasis have a two-fold higher risk to develop NAFLD and a higher risk to progress to more severe liver disease. Psoriasis and NAFLD share common risk factors such as smoking, alcohol consumption, and the presence of metabolic syndrome and its component disorders. In addition, both psoriasis and NAFLD hinge upon a systemic low-grade inflammation that can lead to a vicious cycle of progressive liver damage in NAFLD as well as worsening of the underlying psoriasis. Other important shared pathophysiological pathways include peripheral insulin resistance and oxidative stress. NAFLD should receive clinical awareness as important comorbidity in psoriasis. In this review, we assess the recent literature on the epidemiological and pathophysiological relationship of psoriasis and NAFLD, discuss the clinical implications of NAFLD in psoriasis patients, and summarize the hepatotoxic and hepatoprotective potential of systemic psoriasis therapies.

2-Deoxy-D-glucose Alleviates Collagen-Induced Arthritis of Rats and Is Accompanied by Metabolic Regulation of the Spleen and Liver

Rheumatoid arthritis (RA) is significantly associated with glycolysis. This study used 2-deoxy-D-glucose (2-DG), an inhibitor of glycolysis, to treat rats with collagen-induced arthritis (CIA) and investigate the metabolic regulatory mechanism of glycolysis in the disease. 2-DG significantly alleviated CIA. Metabolomics and transcriptomics, as well as their integrative analysis, detected significant changes in the pathways of bile secretion, cholesterol and linoleic acid metabolism in the plasma, liver and spleen during the CIA process and the opposite changes following 2-DG treatment, whereas the expression of the genes regulating these metabolic pathways were changed only in the spleen. In the rat liver, levels of (S)-5-diphosphomevalonic acid in the terpenoid backbone biosynthesis pathway were significantly decreased during CIA progression and increased following 2-DG treatment, and levels of taurochenodeoxycholic acid in the pentose and glucuronate interconversions pathway showed the opposite results. In the spleen, levels of 3-methoxy-4-hydroxyphenylglycol glucuronide in bile secretion and 12(S)-leukotriene B4 in arachidonic acid metabolism were significantly decreased during CIA progression and increased following 2-DG treatment. The changes in the gene-metabolite network of bile secretion in the spleen correlated with a decreased plasma L-acetylcarnitine level in CIA rats and an increase following 2-DG treatment. Our analysis suggests the involvement of spleen and liver metabolism in CIA under the control of glycolysis.

Systems pharmacology-based dissection of mechanisms of Tibetan medicinal compound Ruteng as an effective treatment for collagen-induced arthritis rats

ETHNOPHARMACOLOGICAL RELEVANCE

Compound Ruteng (CRT) is a prescribed formulation based on the theory of Tibetan medicine for the treatment of yellow-water-disease. It is consisted with 7 medicinal material include Boswellia carterii Birdw (named "Ruxiang" in Chinese); Tinospora sinensis (Lour.) Merr. (named "Kuan-Jin-Teng" in Chinese), Cassia obtusifolia L (named "Jue-Ming-Zi" in Chinese); Abelmoschus manihot (L.) Medic (named "Huang-Kui-Zi" in Chinese); Terminalia chebula Retz. (named "He-Zi" in Chinese); Lamiophlomis rotata (Benth.) Kudo (named "Du-Yi-Wei" in Chinese) and Pyrethrum tatsienense (Bur. et Franch.) Ling (named "Da-Jian-Ju" in Chinese). They are widely distributed in Tibet area of China and have been used to treat rheumatism, jaundice, and skin diseases for centuries.

AIM OF THE STUDY

The present study was conducted to investigate the anti-arthritis effect of CRT and to disclose the systems pharmacology-based dissection of mechanisms.

MATERIALS AND METHODS

The chemical constituents in CRT were identified using HPLC method, and CRT candidate targets against RA were screened by network pharmacology-based analysis and further experimentally validated based on collagen-induced arthritis (CIA) rat model. Furthermore, therapeutic mechanisms and pathways of CRT were investigated.

RESULTS

391 potential targets (protein) were predicted against 92 active ingredients of 7 medicinal materials in CRT. Enrichment analysis and molecular docking studies also enforced the practiced results. X-ray based physiological imaging showed the attenuated effect of CRT on paw swelling, synovial joints and cartilage with improved inflammation in CIA rats. Moreover, the expression of biomarkers associated with RA such as MMP1, MMP3 and MMP13 and TNF-a, COX2 and iNOS are down-regulated in ankle joints, serum, or liver.

CONCLUSION

In conclusion, CRT compound could attenuate RA symptoms and active ingredients of this compound could be considered for drug designing to treat RA.

Methotrexate use does not increase the prevalence of hepatic steatosis: a real-world retrospective nested case-control study

OBJECTIVE

We aimed to determine whether methotrexate (MTX) treatment in patients with rheumatoid arthritis (RA) leads to the development of non-alcoholic fatty liver (NAFL).

METHOD

Data were derived from records of all patients with RA who underwent abdominal ultrasonography at the Jeonbuk National University Hospital. Patients with ultrasound-proven NAFL were identified, and those without NAFL were matched by age and sex using the propensity score matching method at 1:3 ratio. We also analyzed the Health Insurance Review and Assessment Service-National Patient Samples, a nationwide cohort database, to determine the association between MTX use and NAFL in a large number of patients (n = 24,653).

RESULTS

In the hospital cohort, 92 patients with NAFL did not show significant differences in the cumulative MTX dose when compared with the no-NAFL group (n = 276) (1908.5 ± 1757.5 vs. 1948.6 ± 2118.8 mg, p = 0.911). The prevalence of NAFL was not significantly different across strata of cumulative MTX dose. Multiple logistic analyses identified hypertriglyceridemia (OR, 4.88 [95% CI, 1.13-20.93]) and higher body mass index (OR, 1.22 [95% CI, 1.05-1.41]) as being associated with an increased risk of NAFL. In the nationwide cohort, the MTX exposure rate between the NAFL and no-NAFL groups was not significantly different.

CONCLUSIONS

Collectively, no significant association between NAFL development and administration of MTX was detected in this study. Our results suggest that it is more efficient to adjust for individualized risk factors for NAFL prevention rather than discontinuation of MTX in patients with RA. Key Points • NAFLD has been highlighted with increasing prevalence worldwide and possible progression to end-stage liver disease. • Cumulative dose or exposure history of MTX does not show a significant association with NAFLD prevalence. • Modifying well-established risk factors is more efficient in NAFLD prevention rather than discontinuation of MTX.

The impact of bariatric surgery on in-patient clinical outcomes among patients with autoimmune hepatitis

Autoimmune hepatitis (AIH) is a form of liver inflammation in which immune cells target hepatocytes, inducing chronic inflammatory states. Bariatric surgery (BS) was shown to reduce inflammation in severely obese patients. We hypothesize that obese patients with AIH and BS have lower prevalence of liver-related complications and in-patient mortality compared to those without BS.The National Inpatient Sample from 2007 to 2013 was queried for hospitalizations of adults over 18 years of age with a diagnosis of AIH. Of those, hospitalizations with BS were selected as cases and those with morbid obesity as controls. Case-control 1:2 matching was done based on sex, age, race, and comorbidities. Primary outcomes were prevalence of liver-related complications and in-patient mortality. Independent risk factors of in-patient clinical outcomes were identified using multivariate regression analysis.From 137,834 hospitalizations with a diagnosis of AIH, 688 with BS were selected as cases, and 1295 were matched as controls. The prevalence of ascites was higher in the BS group compared to the control (odds ratio 1.73, 95% confidence interval (CI) 1.27-2.36). The prevalence of cirrhosis (36.8% vs 33.2%), portal hypertension (7.4% vs 10.0%), hepatic encephalopathy (10.6% vs 8.7%), and varices and variceal bleeding (3.9% vs 5.5%) was not statistically different from case controls, (P > .05).BS was an independent risk factor for ascites (adjusted odds ratio (aOR) 1.87; 95% CI 1.36-2.56) and hepatic encephalopathy (aOR 1.42; 95% CI 1.03-1.97) but was an independent protective factor against in-patient mortality (aOR 0.21, 95% CI 0.08-0.55) once adjusted for age, sex, race, and comorbidities.

Clinical Characteristics of Systemic Lupus Erythematosus with Cirrhosis

Aim

Cirrhosis is rare in systemic lupus erythematosus (SLE) patients with a poor prognosis. This study is aimed at retrospectively analyzing our single-center experience to explore the characteristics of cirrhosis in SLE patients.

Methods

SLE patients with cirrhosis from 2012 to 2019 were enrolled. SLE diagnosis was rigorously confirmed by a medical record review according to the revised 1997 American College of Rheumatology classification criteria for SLE. The diagnosis of liver cirrhosis was based on a combination of clinical, laboratory, and imaging criteria features. We conducted a case-control study in SLE patients complicated with the cirrhosis group and the age-, sex-, and entry-time-matched noncirrhosis group.

Results

A total of 21 patients with SLE cirrhosis were enrolled, 3 males and 18 females. The median age at the time of cirrhosis diagnosis was 47.3 ± 4.0 years, and the mean disease duration of SLE before cirrhosis was 4.7 ± 1.0 years. The most common initial presentation was the involvement of the hematological system in 9 patients and then skin and mucosal involvement in 5 patients, arthritis in 4 patients, and nephritis in 3 patients. Patients with cirrhosis had a significantly higher rate of hematological system involvement (thrombocytopenia and leukopenia) and worse liver function; a higher level of immune globulin G had higher mortality (p < 0.05) than patients without cirrhosis.

Conclusions

Cirrhosis is a rare and severe subtype of SLE with a poor prognosis. Those patients with hematological system involvement and impaired liver function should be paid more attention.