Anti-CCP in systemic lupus erythematosus patients: a cross sectional study in Brazilian patients

Examining the clinical and radiological landscape of rhupus: navigating the challenges in disease classification

Rhupus, in the broad sense, refers to an overlap between rheumatoid arthritis (RA) and lupus. However, there is a paucity of data on the appropriate diagnostic/classification criteria that should be used to define rhupus. Hence, we undertook this narrative review to analyze the clinical characteristics, radiology, and treatment with a focus on diagnostic challenges and defining features of rhupus. The databases of Medline/PubMed, Scopus, and DOAJ were searched for relevant articles using the following keywords: ("Rhupus"), ("lupus" AND "erosive" AND "arthritis"), and ("lupus" AND "rheumatoid arthritis" AND "overlap"). Studies have used a variety of classification criteria for rhupus of which a combination of the latest classification criteria for RA and lupus along with positive anti-cyclic citrullinated peptide, anti-Smith, and anti-dsDNA antibodies seem most relevant. The majority of rhupus cohorts report the onset of the disease as RA (two-thirds of rhupus patients) followed by the development of features of lupus at an average interval of 3-11.3 years. The radiographic features and distribution of erosions are similar to RA. However, ultrasonography and MRI reveal erosions in pure lupus related arthritis as well. This makes the reliability of radiologic tools for the evaluation of rhupus supportive at the most. Extra-articular features in rhupus are mild with major organ involvement in the form of neuropsychiatric lupus and lupus nephritis being rare. We have further discussed the fallacies of the various classification criteria and proposed a theme for classifying rhupus which needs to be tested and validated in future studies. Our current state of understanding supports rhupus as an overlap of SLE and RA with articular disease similar to RA with the extra-articular disease being milder than SLE. Developing standardized classification criteria for rhupus will help in the early diagnosis and prevention of articular damage in patients with rhupus.

Anti-Citrullinated Peptide Antibody Expression and Its Association with Clinical Features and Outcomes in Patients with Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

Background and objectives: Anti-citrullinated peptide antibody (ACPA), a characteristic antibody detected in rheumatoid arthritis, could be linked to antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) via the formation of neutrophil extracellular traps. We investigated the rate of ACPA positivity in patients with AAV and evaluated the association of ACPAs with their clinical features and outcomes. Materials and Methods: A total of 168 AAV patients with both ACPA and ANCA results at diagnosis were identified. Clinical and laboratory variables, including the disease-specific indices of Birmingham Vasculitis Activity Score (BVAS) and Five-Factor Score (FFS), were investigated. All-cause mortality, relapse, and end-stage renal disease, as well as interstitial lung disease (ILD) were evaluated as outcomes of the patients, and the Kaplan–Meier survival analysis was used to compare the event-free survival rates of the groups. Results: Fifteen (8.9%) and 135 (80.4%) patients were positive for ACPA and ANCA, respectively. There were no significant differences in the baseline variables of ACPA-negative and ACPA-positive patients. The absolute titre of ACPAs also did not significantly correlate with BVAS, FFS, erythrocyte sedimentation rate, or C-reactive protein. In addition, there was no difference noted regarding overall, relapse-free, and ESRD-free survival rates between ACPA-negative and ACPA-positive AAV patients. However, when the patients were divided into four groups according to ACPA and ANCA status, differences were present in the outcomes, and the ACPA-positive ANCA-positive group exhibited the lowest cumulative relapse-free survival rate, while no significant difference was present in the relapse between the ANCA-positive ANCA-positive, ACPA-positive ANCA-negative, and ACPA-negative ANCA-positive groups. Finally, the cumulative ILD-free survival rates were comparable between ACPA-positive and ACPA-negative AAV patients. Conclusions: The detection of ACPA expression is not uncommon in AAV. However, the presence of ACPA did not influence patients’ basal characteristics and outcomes, suggesting that further exploration of the role of this antibody is needed in patients with AAV.

Erosive arthritis in systemic lupus erythematosus: not only Rhupus

Systemic lupus erythematosus (SLE)-related arthritis has been traditionally defined as non-erosive and is therefore considered a minor manifestation requiring a mild treatment. However, the concept of non-erosive arthritis in SLE has been challenged with the advent of sensitive imaging techniques, such as high-resolution ultrasound with power Doppler or magnetic resonance. The application of these new imaging tools has demonstrated that up to 40% of SLE patients with joint involvement can develop erosive damage. Thus, this more aggressive phenotype can be identified not only in patients overlapping with rheumatoid arthritis (RA). This issue has been considered for the first time in the classification criteria proposed by Systemic Lupus International Collaborating Clinics in 2012, in which the old definition of "non-erosive arthritis" was replaced with either synovitis or tenderness in two or more joints with morning stiffness, suggesting the possible presence of an erosive phenotype. Accordingly, the 2019 EULAR/ACR's SLE recommendations advise treatment with immunosuppressant or biological drugs for patients with RA-like moderate arthritis. As a result, several studies have investigated the presence of biomarkers associated with SLE erosive damage. A relevant role seems to be played by the autoantibodies directed against post-translational modified proteins: above all, a significant association has been observed with antibodies directed against citrullinated and carbamylated proteins. Conversely, the rheumatoid factor was not associated with this more aggressive SLE-related arthritis. Nonetheless, some pro-inflammatory factors have been associated with erosive damage in SLE patients. These results suggest new pathogenic mechanisms underlining erosive arthritis, only partially shared with RA. Hence, in the present narrative review, we summarized available data about erosive arthritis in SLE patients, in the light of its impact on therapeutic decisions.

Latent autoimmunity across disease-specific boundaries in at-risk first-degree relatives of SLE and RA patients

BACKGROUND

Autoimmune disease prevention requires tools to assess an individual's risk of developing a specific disease. One tool is disease-associated autoantibodies, which accumulate in an asymptomatic preclinical period. However, patients sometimes exhibit autoantibodies associated with a different disease classification. When and how these alternative autoantibodies first appear remain unknown. This cross-sectional study characterizes alternative autoimmunity, and associated genetic and environmental factors, in unaffected first-degree relatives (FDRs) of patients, who exhibit increased future risk for the same disease.

METHODS

Samples (n = 1321) from disease-specific autoantibody-positive (aAb+) systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and type 1 diabetes (T1D) patients; and unaffected aAb+ and autoantibody-negative (aAb-) SLE and RA FDRs were tested for SLE, RA, and T1D aAbs, as well as anti-tissue transglutaminase, anti-cardiolipin and anti-thyroperoxidase. FDR SLE and RA genetic risk scores (GRS) were calculated.

FINDINGS

Alternative autoimmunity occurred in SLE patients (56%) and FDRs (57·4%), RA patients (32·6%) and FDRs (34·8%), and T1D patients (43%). Expanded autoimmunity, defined as autoantibodies spanning at least two other diseases, occurred in 18·5% of SLE patients, 16·4% of SLE FDRs, 7·8% of RA patients, 5·3% of RA FDRs, and 10·8% of T1D patients. SLE FDRs were more likely to have alternative (odds ratio [OR] 2·44) and expanded (OR 3·27) autoimmunity than RA FDRs. Alternative and expanded autoimmunity were associated with several environmental exposures. Alternative autoimmunity was associated with a higher RA GRS in RA FDRs (OR 1·41), and a higher SLE GRS in aAb+ RA FDRs (OR 1·87), but not in SLE FDRs.

INTERPRETATION

Autoimmunity commonly crosses disease-specific boundaries in systemic (RA, SLE) and organ-specific (T1D) autoimmune diseases. Alternative autoimmunity is more common in SLE FDRs than RA FDRs, and is influenced by genetic and environmental factors. These findings have substantial implications for preclinical disease pathogenesis and autoimmune disease prevention studies. FUND: NIH U01AI101981, R01AR051394, U19AI082714, P30AR053483, P30GM103510, U54GM104938, U01AI101934, R01AI024717, U01AI130830, I01BX001834, & U01HG008666.

The Micro-RNA Expression Profiles of Autoimmune Arthritis Reveal Novel Biomarkers of the Disease and Therapeutic Response

Rheumatoid arthritis (RA) is a chronic autoimmune disease of the joints affecting about 0.3–1% of the population in different countries. About 50–60 percent of RA patients respond to presently used drugs. Moreover, the current biomarkers for RA have inherent limitations. Consequently, there is a need for additional, new biomarkers for monitoring disease activity and responsiveness to therapy of RA patients. We examined the micro-RNA (miRNA) profile of immune (lymphoid) cells of arthritic Lewis rats and arthritic rats treated with celastrol, a natural triterpenoid. Experimental and bioinformatics analyses revealed 8 miRNAs (miR-22, miR-27a, miR-96, miR-142, miR-223, miR-296, miR-298, and miR-451) and their target genes in functional pathways important for RA pathogenesis. Interestingly, 6 of them (miR-22, miR-27a, miR-96, miR-142, miR-223, and miR-296) were further modulated by celastrol treatment. Interestingly, serum levels of miR-142, miR-155, and miR-223 were higher in arthritic versus control rats, whereas miR-212 showed increased expression in celastrol-treated rats compared with arthritic rats or control rats. This is the first study on comprehensive miRNA expression profiling in the adjuvant-induced arthritis (AA) model and it also has revealed new miRNA targets for celastrol in arthritis. We suggest that subsets of the above miRNAs may serve as novel biomarkers of disease activity and therapeutic response in arthritis.

Rhupus syndrome and Chiari's network

A 69-year-old female patient was admitted to our clinic with photosensitivity, symmetric erosive polyarthritis, and cutaneous vasculitis of lower extremities. Rhupus syndrome was diagnosed, and Chiari's network in the right atrium and interatrial septum patent foramen ovale was achieved on transthoracic and transesophageal echocardiography. If it is thought that increased prevalence of antiphospholipid antibodies in patients with rhupus, this congenital remnant is important for the thrombosis risk, cardiac event, and stroke. The association of both diseases may lead to more serious events and cause worse prognosis. Here, our aim is to present a 69-year-old female patient with rhupus syndrome presenting with cutaneous vasculitis and Chiari's network in the right atrium.

Anti-carbamylated protein antibodies in systemic lupus erythematosus patients with articular involvement

Objective Several studies have evaluated the prevalence of rheumatoid factor (RF) and anti-citrullinated proteins antibodies (ACPA) in systemic lupus erythematosus (SLE) patients but no data are available on the anti-carbamylated proteins (anti-CarP), a new biomarker for rheumatoid arthritis (RA). We evaluated the anti-CarP prevalence in SLE patients with joint involvement and the associations with different phenotypes. Methods Seventy-eight SLE patients with joint involvement were enrolled (F/M 73/5; mean ± SD age 47.6 ± 11.2 years; mean ± SD disease duration 214.3 ± 115.6 months). As control groups, we evaluated SLE patients without joint manifestations ( N = 15), RA ( N = 78) and healthy individuals (HS, N = 98). Anti-CarP were assessed by home-made ELISA in all patients and controls, RF and ACPA in SLE patients with joint involvement (commercial ELISA kit). Results The prevalence of anti-CarP in SLE patients with joint involvement was similar to RA ( p = NS) and significantly higher compared with SLE without joint involvement and HS ( p < 0.0001, p < 0.0001, respectively). Four patients were positive for all three antibodies: seventy-five percent of these showed Jaccoud arthropathy. Fourty-five percent of ACPA-ve/RF-ve patients were anti-CarP + ve. Conclusions The evaluation of anti-CarP in SLE joint involvement demonstrated a prevalence of almost 50%, similar to RA and significantly higher than SLE without joint involvement and HS.

Antibodies against carbamylated proteins and cyclic citrullinated peptides in systemic lupus erythematosus: results from two well-defined European cohorts

BACKGROUND

Articular manifestations are common in systemic lupus erythematosus (SLE) whereas erosive disease is not. Antibodies to cyclic citrullinated peptide (anti-CCP) are citrulline-dependent in rheumatoid arthritis (RA), whereas the opposite is suggested in SLE, as reactivity with cyclic arginine peptide (CAP) is typically present. Antibodies targeting carbamylated proteins (anti-CarP) may occur in anti-CCP/rheumatoid factor (RF)-negative cases long before clinical onset of RA. We analysed these antibody specificities in sera from European patients with SLE in relation to phenotypes, smoking habits and imaging data.

METHODS

Cases of SLE (n = 441) from Linköping, Sweden, and Leiden, the Netherlands, were classified according to American College of Rheumatology (ACR) and/or Systemic Lupus Erythematosus International Collaborating Clinics (SLICC) criteria. IgG anti-CCP, anti-CAP and anti-CarP were analysed by immunoassays. Radiographic data from 102 Swedish patients were available.

RESULTS

There were 16 Linköping (6.8%) and 11 Leiden patients (5.4%) who were anti-CCP-positive, of whom approximately one third were citrulline-dependent: 40/441 (9.1%) were anti-CarP-positive, and 33% of the anti-CarP-positive patients were identified as anti-CCP-positive. No associations were found comparing anti-CCP or anti-CarP with ACR-defined phenotypes, immunologic abnormalities or smoking habits. Radiographically confirmed erosions were found in 10 patients, and were significantly associated with anti-CCP, anti-CarP and RF. Musculoskeletal ultrasonography scores were higher in anti-CCP-positive compared to anti-CCP-negative patients.

CONCLUSIONS

In the hitherto largest anti-CarP study in SLE, we demonstrate that anti-CarP is more prevalent than anti-CCP and that the overlap is limited. We obtained some evidence that both autoantibodies seem to be associated with erosivity. Similar pathogenetic mechanisms to those seen in RA may be relevant in a subgroup of SLE cases with a phenotype dominated by arthritis.

Factors Associated with Erosive Arthritis in Rheumatoid Arthritis and Other Connective Tissue Diseases: A Retrospective Study From a Southern Chinese Population

OBJECTIVE

To investigate the clinical predictors of erosive arthritis (EA) in patients with rheumatoid arthritis (RA) and other connective tissue diseases.

METHODS

Four hundred and one consecutive patients with newly diagnosed RA between January 2010 and January 2013 were enrolled in the study. During the study period, 729 consecutive patients with non-RA connective tissue diseases were also included, and a cross-sectional study was performed. Medical records were reviewed. Only those patients with data for 2 years were considered in the analysis (338).

RESULTS

Erosive arthritis was noted in 60.4% (204 /338) of patients with RA and occurred early in RA. The multivariate logistic regression analysis indicated that rheumatoid nodules, anemia, and positive anticyclic citrullinated peptide antibody (ACPA) were strongly associated factors for the occurrence of EA in RA patients. Erosive arthritis was also noted in 1.5% of patients with SLE, 5.8% of patients with primary Sjögren syndrome, and 9.1% (3/33) of patients with systemic sclerosis. When compared with patients without EA, high level and prominently higher positive rate of ACPA was found in these patients with EA. On receiver operating characteristic curve analysis, ACPA exhibited a maximum sensitivity with a cutoff value of 1.6 U/mL and 0.6 U/mL for RA and SLE patients, respectively.

CONCLUSION

Erosive arthritis had a high prevalence in Chinese RA patients and occurred early. Anemia, rheumatoid nodules, and ACPA were associated with EA in RA. Erosive arthritis also could be detected in SLE, primary Sjögren syndrome, and systemic sclerosis. Anticyclic citrullinated peptide antibodies were also associated with EA in these diseases. Intensive monitoring for erosions was recommended for RA patients with a cutoff of ACPA greater than 1.6 U/mL and greater than 0.6 U/mL for SLE patients.

Rhupus; unusual presentations

BACKGROUND

The coexistence of systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) named Rhupus is an unusual clinical condition. Previous reports mentioned that Rhupus patients have prominent RA-associated clinical manifestations and only mild organic damage related to SLE. Progressive or life-threatening manifestations are rare in Rhupus patients.

METHODS

Three patients with Rhupus are described in this article. Two of them presented antiphospholipid syndrome (APS) in addition to Rhupus. Also, we searched for similar cases in published literature.

RESULTS

We present three patients with Rhupus syndrome. One of the patients has only Rhupus, the second patient has Rhupus and APS, and the third patient has Rhupus accompanied by severe Raynaud's syndrome with digital ulcers, APS, pulmonary hypertension and two malignancies. Several studies have shown that Rhupus patients have an increased prevalence of positive antiphospholipid antibodies that resembles SLE. However, the presence of these antibodies is not associated with APS. There is only one case of Rhupus with secondary APS in which the patient presented headache and papilloedema due to cerebral venous thrombosis. Secondary Raynaud's syndrome is rare in Rhupus patients, and to the best of our knowledge, only three cases of this are mentioned in literature. Secondary pulmonary hypertension and malignancies were never reported before in Rhupus patients.

CONCLUSIONS

Rheumatologists should be aware of the possibility that Rhupus may be accompanied by progressive or life-threatening conditions such as APS, severe Raynaud's syndrome with digital ulcers, pulmonary hypertension, or malignancies.

Mining disease risk patterns from nationwide clinical databases for the assessment of early rheumatoid arthritis risk

Rheumatoid arthritis (RA) is a chronic autoimmune rheumatic disease that can cause painful swelling in the joint lining, morning stiffness, and joint deformation/destruction. These symptoms decrease both quality of life and life expectancy. However, if RA can be diagnosed in the early stages, it can be controlled with pharmacotherapy. Although many studies have examined the possibility of early assessment and diagnosis, few have considered the relationship between significant risk factors and the early assessment of RA. In this paper, we present a novel framework for early RA assessment that utilizes data preprocessing, risk pattern mining, validation, and analysis. Under our proposed framework, two risk patterns can be discovered. Type I refers to well-known risk patterns that have been identified by existing studies, whereas Type II denotes unknown relationship risk patterns that have rarely or never been reported in the literature. These Type II patterns are very valuable in supporting novel hypotheses in clinical trials of RA, and constitute the main contribution of this work. To ensure the robustness of our experimental evaluation, we use a nationwide clinical database containing information on 1,314 RA-diagnosed patients over a 12-year follow-up period (1997-2008) and 965,279 non-RA patients. Our proposed framework is employed on this large-scale population-based dataset, and is shown to effectively discover rich RA risk patterns. These patterns may assist physicians in patient assessment, and enhance opportunities for early detection of RA. The proposed framework is broadly applicable to the mining of risk patterns for major disease assessments. This enables the identification of early risk patterns that are significantly associated with a target disease.

Breaking immunological tolerance in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a fairly heterogeneous autoimmune disease of unknown etiology that mainly affects women in the childbearing age. SLE is a prototype type III hypersensitivity reaction in which immune complex depositions cause inflammation and tissue damage in multiple organs. Two distinct cell death pathways, apoptosis and NETosis, gained a great deal of interest among scientists, since both processes seem to be deregulated in SLE. There is growing evidence that histone modifications induced by these cell death pathways exert a central role in the induction of autoimmunity. In the current review, we discuss how abnormalities in apoptosis, NETosis, and histone modifications may lead to a break of immunological tolerance in SLE.