Distinctive autoantibody profile in Mexican Mestizo systemic sclerosis patients

A Prospective Observational Study of Disease Severity and Mortality in Hispanic American Patients With Systemic Sclerosis

OBJECTIVE

To characterize disease manifestations in Hispanic American patients with systemic sclerosis (SSc) in comparison with non-Hispanic White and Black patients.

METHODS

Longitudinal clinical characteristics were collected prospectively in the Genetics versus Environment in Scleroderma Outcome Study cohort. All patients fulfilled the classification criteria for SSc and had a disease duration less than five years at enrollment.

RESULTS

A cohort of 427 patients, consisting of 124 Hispanic, 220 non-Hispanic White, and 83 non-Hispanic Black participants were examined. At enrollment, Hispanic patients were significantly younger but had longer disease duration, higher frequency of U1-RNP positivity as well as concurrent systemic lupus erythematosus (SLE) diagnosis, and lower income and educational levels in comparison to non-Hispanic White patients. Compared with non-Hispanic Black patients, Hispanic patients had more frequently limited cutaneous involvement and anticentromere antibodies. In the longitudinal analysis, Hispanic patients had significantly lower forced vital capacity percents predicted (point estimate, -9.3%; P < 0.001) than non-Hispanic White but not Black patients. Hispanic patients had similar longitudinal modified Rodnan Skin Scores like non-Hispanic White patients but lower measurements than non-Hispanic Black patients (point estimate, -3.2; P = 0.029). Hispanic patients had significantly higher serially obtained perceived functional disability scores than White patients (point estimate, 0.29; P < 0.001). Hispanic patients also had higher mortality rates than White Americans even after adjustment for age, gender, and socioeconomic statuses.

CONCLUSION

Hispanic patients have higher likelihood of having U1-RNP positivity and SLE overlap, more severe restrictive lung disease, as well as higher rate of mortality than non-Hispanic White patients.

Combination of Sjögren's syndrome and anti-Ku syndrome complicated by the development of mucosa-associated lymphoid tissue lymphoma: case review and systematic review of the literature

The frequency of antibodies to Ku varies in various autoimmune diseases. In 2019, Spielmann et al. identified two types of anti-Ku syndrome based on a hierarchical clustering analysis. Sjögren's syndrome occurs both in the first type of anti-Ku syndrome and in the second type. Despite the fact that increased tissue expression of Ku proteins was noted in lymphocytic cells with focal sialoadenitis of the minor salivary glands in patients with primary Sjogren's syndrome, only 49 cases of a combination of anti-Ku antibodies and manifestations of Sjogren's syndrome have been described in the literature. Some researchers examined patients for the presence of Sjogren's syndrome only if they had anti-Ro or anti-La antibodies, although in the literature, there are descriptions of Sjogren's syndrome in the presence of only isolated anti-Ku antibodies, as in our case. Literature data on glandular and extraglandular manifestations of Sjögren's syndrome in anti-Ku-positive patients are limited. Below, we present the first case of Sjögren's syndrome in combination with the first type of anti-Ku syndrome complicated by the development of mucosa-associated lymphoid tissue (MALT) lymphoma. The article also provides a systematic review of the literature on the association of Sjögren's syndrome with anti-Ku antibodies.

Right Ventricle and Autoimmune Diseases

Autoimmune diseases can express pathologies in specific organs (e.g. thyroid, pancreas, skin) or generate systemic pathologies (generalized lupus erythematosus, rheumatoid arthritis, systemic sclerosis), the latter usually present systemic inflammatory phenomena. Some studies have reported alterations in right ventricular contractility in patients with rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, and juvenile idiopathic arthritis, which may contribute to the known outcome of increased cardiovascular risk. However, there is not much information available on the causes that generate these alterations, the most likely being small vessel damage and fibrosis due to subclinical inflammation.1-5 In this sense, the disease in which the alterations of the right ventricle have been more studied is systemic sclerosis, specifically at the changes induced due to pulmonary arterial hypertension, this being one of the main causes of death in this group of patients after the significant decrease in mortality associated with the sclerodermic renal crisis with the treatment of angiotensin-converting enzyme inhibitors. In this review, we will focus on explaining the structural and functional changes that occur in the right ventricle of patients with systemic sclerosis, from early alterations to late complications. In this context, it is necessary to distinguish between right heart alterations that occur in patients with systemic sclerosis and pulmonary arterial hypertension and those that occur without pulmonary arterial hypertension and that can be attributed to other causes such as microvascular damage or myocardial fibrosis.

Consensus on the assessment of systemic sclerosis-associated primary heart involvement: World Scleroderma Foundation/Heart Failure Association guidance on screening, diagnosis, and follow-up assessment

Introduction

Heart involvement is a common problem in systemic sclerosis. Recently, a definition of systemic sclerosis primary heart involvement had been proposed. Our aim was to establish consensus guidance on the screening, diagnosis and follow-up of systemic sclerosis primary heart involvement patients.

Methods

A systematic literature review was performed to investigate the tests used to evaluate heart involvement in systemic sclerosis. The extracted data were categorized into relevant domains (conventional radiology, electrocardiography, echocardiography, cardiac magnetic resonance imaging, laboratory, and others) and presented to experts and one patient research partner, who discussed the data and added their opinion. This led to the formulation of overarching principles and guidance statements, then reviewed and voted on for agreement. Consensus was attained when the mean agreement was ⩾7/10 and of ⩾70% of voters.

Results

Among 2650 publications, 168 met eligibility criteria; the data extracted were discussed over three meetings. Seven overarching principles and 10 guidance points were created, revised and voted on. The consensus highlighted the importance of patient counseling, differential diagnosis and multidisciplinary team management, as well as defining screening and diagnostic approaches. The initial core evaluation should integrate history, physical examination, rest electrocardiography, trans-thoracic echocardiography and standard serum cardiac biomarkers. Further investigations should be individually tailored and decided through a multidisciplinary management. The overall mean agreement was 9.1/10, with mean 93% of experts voting above 7/10.

Conclusion

This consensus-based guidance on screening, diagnosis and follow-up of systemic sclerosis primary heart involvement provides a foundation for standard of care and future feasibility studies that are ongoing to support its application in clinical practice.

Training the Next Generation of Rheumatologists: What Is the Best Way to Teach Fellows About Scleroderma?

Rheumatology is rich in educational opportunities, learning about a variety of diseases. Rheumatology subspecialty training is a time of unparalleled learning, and within the curriculum of a training program, the connective tissue diseases (CTDs) represent a unique challenge to the fellows. The challenge therein lies in the multisystem presentations they are faced with mastering. Scleroderma, as a rare and life-threatening CTD, remains one of the most difficult conditions to manage and treat. In this article, the authors focus on an approach to training the next generation of rheumatologists to take care of patients with scleroderma.

Clinical and serological correlation of systemic sclerosis in Moroccan patients

Objective

SSc is a CTD characterized by excessive fibrosis of the skin and internal organs, along with microvascular damage, and is often associated with typical autoantibodies. The aim of this study was to analyse the correlation between specific autoantibody profiles, clinical and paraclinical features in Moroccan patients with SSc.

Methods

We analysed the presence of specific autoantibodies in 46 SSc patients using IIF on HEp-2 cells and immunodot. We then correlated the types of autoantibodies with clinical and laboratory manifestations.

Results

Among our patients, 86.9% were females. The mean age of patients at diagnosis was 50.21 years, with an average delay to diagnosis of 5 years. The main clinical manifestations found were RP (89.2%), sclerodactyly (84.8%), proximal scleroderma (67.4%), gastrointestinal involvement (50%) and interstitial lung disease (30.4%). According to the specific autoantibody profile, 14 patients were anti-topo I positive (30.4%), 8 anti-RNP (68 kDa/A/C) positive (17.4%) and 6 anti-RNA polymerase III positive (13%). We found a significant association of anti-RNA polymerase III with sclerodactyly and pulmonary arterial hypertension (P < 0.05). We also found an association between anti-topo I and interstitial lung disease in 30.4% of patients. There was no significant association between the positivity for the autoantibodies and other diagnosed clinical manifestations.

Conclusion

Some clinical manifestations of SSc might be positively correlated with the presence of specific autoantibodies. Environmental factors, ethnicity and gene interaction might also influence this correlation.

Scleromyositis: A distinct novel entity within the systemic sclerosis and autoimmune myositis spectrum. Implications for care and pathogenesis

Systemic sclerosis and autoimmune myositis are both associated with decreased quality of life and increased mortality. Their prognosis and management largely depend on the disease subgroups. Indeed, systemic sclerosis is a heterogeneous disease, the two predominant forms of the disease being limited and diffuse scleroderma. Autoimmune myositis is also a heterogeneous group of myopathies that classically encompass necrotizing myopathy, antisynthetase syndrome, dermatomyositis and inclusion body myositis. Recent data revealed that an additional disease subset, denominated "scleromyositis", should be recognized within both the systemic sclerosis and the autoimmune myositis spectrum. We performed an in-depth review of the literature with the aim of better delineating scleromyositis. Our review highlights that this concept is supported by recent clinical, serological and histopathological findings that have important implications for patient management and understanding of the disease pathophysiology. As compared with other subsets of systemic sclerosis and autoimmune myositis, scleromyositis patients can present with a characteristic pattern of muscle involvement (i.e. distribution of muscle weakness) along with multisystemic involvement, and some of these extra-muscular complications are associated with poor prognosis. Several autoantibodies have been specifically associated with scleromyositis, but they are not currently integrated in diagnostic and classification criteria for systemic sclerosis and autoimmune myositis. Finally, striking vasculopathic lesions at muscle biopsy have been shown to be hallmarks of scleromyositis, providing a strong anatomopathological substratum for the concept of scleromyositis. These findings bring new insights into the pathogenesis of scleromyositis and help to diagnose this condition, in patients with subtle SSc features and/or no autoantibodies (i.e. "seronegative" scleromyositis). No guidelines are available for the management of these patients, but recent data are showing the way towards a new therapeutic approach dedicated to these patients.

Autoantibodies and Clinical Correlations in Polish Systemic Sclerosis Patients: A Cross-Sectional Study

We evaluated the prevalence of systemic sclerosis (SSc)-related autoantibodies and their clinical significance and compared the sensitivity of two line immunoblot assays on a prospective study group of 96 Polish SSc patients (ACR-EULAR 2013 criteria) whose sera were assessed by indirect immunofluorescence (HEp-2 and monkey liver) and line immunoblot assays: ANA Profile 3 and Systemic Sclerosis Profile by EUROIMMUN (Lübeck, Germany). Organ involvement was evaluated according to the EUSTAR Minimal Essential Data Set. The following autoantibodies’ prevalence was found: Scl-70 (36%), Ro-52 (28%), CENP-B (22%), CENP-A (20%), PM-Scl-75 (20%), PM-Scl-100 (14%), fibrillarin (7%), Th/To (7%), RNA polymerase III 11 kDa (5%), RNA polymerase III 155 kDa (3%), PDGFR (3%), NOR-90 (2%), and Ku (1%). Significant associations between the autoantibodies’ presence and organ involvement were found: ATA (dcSSc > lcSSc, less prevalent muscle weakness), Ro-52 (gangrene, DLCO < 60), CENP-B and A (lcSSc > dcSSc, normal CK), CENP-B (rarer digital ulcers and joint contractures), PM-Scl-100 and 75 (PM/SSc overlap, CK increase, muscle weakness, muscle atrophy), PM-Scl-100 (dcSSc unlikely), PM-Scl-75 (lung fibrosis), fibrillarin (muscle atrophy, proteinuria, conduction blocks, palpitations), Th/To (proteinuria, arthritis, muscle weakness, and rarer esophageal symptoms), RNA Polymerase III 11 kDa (arterial hypertension, renal crisis), RNA polymerase III 155 kDa (renal crisis), and PDGFR (dcSSc, tendon friction rubs). Additionally, the Systemic Sclerosis Profile was significantly more sensitive in detecting SSc-related autoantibodies than ANA Profile 3 (p = 0.002). In conclusion, individual autoantibodies associated with specific characteristics of SSc.

Clinical Significance of Antinucleolar Antibodies: Biomarkers for Autoimmune Diseases, Malignancies, and others

Nucleolar staining is one of the standard patterns in immunofluorescence antinuclear antibodies (ANA), seen in 5-9% of ANA in various conditions. Antinucleolar antibodies (ANoA) are classified into 3 patterns in the International Consensus on ANA Patterns (ICAP) classification; AC-8 homogeneous pattern, AC-9 clumpy pattern, and AC-10 punctate pattern. Specificities known to show AC-8 include anti-Th/To, -PM-Scl, -nucleophosmin/B23, -nucleolin/C23, -No55, and others. AC-9 is seen by anti-fibrillarin/U3RNP and AC-10 by anti-RNA polymerase I and hUBF/NOR-90. ANoA has been classically known to be associated with scleroderma (SSc) and the characterization of nucleolar antigens identified several autoantigens recognized by SSc autoantibodies. The clinical association of anti-Th/To, PM-Scl, fibrillarin/U3RNP, and RNA polymerase I with SSc or SSc-overlap syndrome is well established, and commercial assays are developed. Anti-hUBF/NOR90, nucleophosmin/B23, and nucleolin/C23 are known for decades and reported in systemic autoimmune rheumatic diseases (SARDs), malignancies, graft versus host disease (GVHD), and others; however, their clinical significance remains to be established.

Epidemiology and Treatment of Systemic Sclerosis in Korea

Systemic sclerosis (SSc), a rare, chronic progressive systemic autoimmune disease of unknown etiology, is characterized by autoimmunity, tissue fibrosis, and obliterative vasculopathy. SSc can affect all major organs including the skin, blood vessels, lung, heart, kidneys, and gastrointestinal tract. Our understanding of its pathogenesis has increased over the past few decades, leading to improved diagnosis and treatment. However, the mortality rate of SSc remains considerable, mainly due to cardiopulmonary causes. A growing body of evidence suggests that geographical, regional, and ethnic differences could affect the epidemiology, clinical characteristics and prognosis of SSc. Although Korean data of this issue are lacking, a considerable amount of research has been published by many Korean researchers. To establish treatment strategies for Korean patients, extensive Korean research data are needed. This review summarizes the prevalence, incidence, mortality, and clinical and laboratory manifestations of Korean patients with SSc and discusses the current trends in evidence-based treatment and recommendations.

Development of Pulmonary Hypertension in Over One-Third of Patients With Th/To Antibody-Positive Scleroderma in Long-Term Follow-Up

OBJECTIVE

This study was undertaken to describe clinical manifestations in patients with Th/To antibody-positive systemic sclerosis (SSc) during long-term follow-up.

METHODS

We performed a case-control study involving anti-Th/To antibody-positive patients with SSc who were newly referred to the University of Pittsburgh Medical Center and the Pittsburgh Scleroderma Center from 1980 to 2015. For every case, 2 anti-Th/To antibody-negative SSc patients (the first 2 consecutively seen after a case) were used as controls. Long-term disease manifestations and survival were then compared between cases and controls.

RESULTS

A total of 204 anti-Th/To antibody-positive SSc patients and 408 controls were identified. The cohort had a mean ± SD age of 52 ± 12.9 years, and 76% of individuals were women. Anti-Th/To antibody-positive patients more often presented without skin thickening (P < 0.0001) and had a higher rate of pulmonary hypertension (PH) (P < 0.0001) and interstitial lung disease (P = 0.05) compared to anti-Th/To antibody-negative SSc controls. Anti-Th/To antibody-positive SSc patients also had less frequent muscle and joint involvement than anti-Th/To antibody-negative SSc controls (P < 0.0001). After a median clinical follow-up period of 6.1 years (interquartile range 2.4-12.7), 38% of anti-Th/To-positive patients had developed PH compared to 15% of anti-Th/To antibody-negative SSc controls (P < 0.0001). The rate of PH classified as World Health Organization (WHO) Group 1 pulmonary arterial hypertension [PAH] was 23% in anti-Th/To-positive patients compared to 9% in anti-Th/To antibody-negative SSc controls (P < 0.0001). After adjusting for age and sex, anti-Th/To antibody positivity was associated with a hazard ratio (HR) of 3.3 (95% confidence interval 2.3-4.9) for increased risk of developing PH at 10 years of follow-up from the first scleroderma center visit.

CONCLUSION

This is the largest cohort of patients with anti-Th/To antibody-positive SSc with long-term follow-up data. The very high rate (38%) and associated independent risk of anti-Th/To antibody-positive patients developing PH in follow-up, particularly in WHO Group 1 PAH patients, is striking. Patients presenting with limited skin involvement should be tested for Th/To antibodies, and if present, careful monitoring for PH is warranted.

Systemic sclerosis manifestations and clinical outcomes in Hispanics/Latinos of the American Southwest

Objective:

Certain Hispanic/Latino (Hispanic) populations have been reported to have higher rates and severity of systemic sclerosis; however, little is known of systemic sclerosis in the American Southwest. This study compared manifestations of systemic sclerosis in Hispanics with non-Hispanics of New Mexico.

Methods:

This cross-sectional longitudinal study included 109 systemic sclerosis patients followed over a mean of 12.6 ± 8.9 years. Subjects were repetitively evaluated including physical examination, echocardiography, chest imaging, and serologic testing and observed for complications. Disease characteristics and long-term outcomes were statistically compared between self-identified Hispanic and non-Hispanic subjects.

Results:

A total of 73 (67%) systemic sclerosis subjects were Hispanic and 36 (33%) were non-Hispanic. The cohorts were similar in mean age, age of systemic sclerosis onset, limited versus diffuse cutaneous systemic sclerosis, telangiectases, gastroesophageal reflux disease, Raynaud’s phenomenon, autoantibody profile, interstitial lung disease, pulmonary hypertension, scleroderma renal crisis, mortality, and comorbid malignancy (all p > 0.05). However, the standardized mortality ratio was increased in both cohorts relative to age-adjusted mortality: Hispanic: 2.08, confidence interval (1.94–2.24); non-Hispanic: 1.56, confidence interval (1.46–1.68). Furthermore, the standardized incidence ratio for malignancy was increased in both cohorts: Hispanic: 1.45, confidence interval (1.35–1.56); non-Hispanic: 1.24, confidence interval (1.16–1.34). The mean age of cancer diagnosis occurred at a significantly younger age in Hispanics (Hispanics: 53.1 ± 9.7 years; non-Hispanics 63.7 ± 7.9 years; 95% confidence interval: −19 ⩽ 10.6 ⩽ 2.2; p = 0.016).

Conclusion:

Systemic sclerosis phenotype, autoantibodies, complications, outcomes, malignancy rates, and mortality are generally similar between Hispanics and non-Hispanics with systemic sclerosis in the American Southwest. However, age-adjusted comorbid malignancy and mortality rates are significantly increased in both groups.

Characterization of Venezuelan patients with systemic sclerosis: a study in a tertiary hospital in Caracas

OBJECTIVE

The aim of the study was to investigate the demographic and clinical characteristics of Venezuelan patients with systemic sclerosis (SSc) seen in a tertiary hospital.

METHODS

Consecutive patients 18 years and older who fulfilled the 2013 ACR/EULAR classification criteria for SSc and who were followed up in the outpatient clinic of the Division of Rheumatology at the Hospital Universitario de Caracas were selected for the study. Demographic and clinical variables were registered at the time of inclusion using a standard protocol.

RESULTS

Forty-eight SSc patients were included; 46 (95.8%) were female; the mean age was 55.1±13.7 (mean±SD) years and all were of Hispanic ethnicity. Thirty-one (64.6%) had limited SSc and 17 (35.4%) had diffuse SSc. The mean duration of disease was 13.4±11.7 (mean±SD) years, 16.74±12.99 years for limited SSc and 7.52±5.25 years for diffuse SSc (p=0.0077). Raynaud's phenomenon was the most frequent manifestation (100%), followed by arthritis (68.8%), telangiectasia (60.4%), dyspnea (60.4%), dysphagia (58.3%) and puffy hands (56.3%). The modified Rodnan Skin Score (mRSS) and the frequency of dyspnea were higher in those with diffuse as compared to limited SSc (p=0.0211 and p=0.0003, respectively). We performed high-resolution computed tomography (HRCT) of the lungs in 31 patients; 14 (45.2%) had evidence of interstitial lung disease (ILD), 11 (68.8%) with diffuse SSc (p=0.0052). The most frequent anti-nuclear antibody pattern was nucleolar, accounting for 18 (42.8%) of the cases. Anti-centromere antibodies were present in 16.7% of the cases and were associated with the limited SSc subset (p=0.0443) and with calcinosis (p=0.0020). Anti-topoisomerase antibodies were associated with ILD (p=0.0077).

CONCLUSIONS

Typical clinical and serological manifestations were present in this sample of Venezuelan patients with SSc, with an expected distribution according to disease subtype. The autoantibody profile allows clinicians to identify those patients with limited forms of the disease and those without pulmonary involvement.

Anti-RNA polymerase III antibodies in systemic sclerosis: Multicentric study from Argentina

OBJECTIVE

To describe the frequency of anti-RNA polymerase III antibody in patients with Systemic Sclerosis (SSc) of a group of healthcare centres from Argentina and to explore differences among patients with positive and negative anti-RNA polymerase III antibody.

PATIENTS AND METHODS

Data from clinical records, anamnesis and physical examination were collected from 135 patients with SSc (ACR/EULAR 2013). A serum sample from each patient was obtained for the detection of anti-RNA polymerase III IgG antibodies by ELISA.

RESULTS

In all, 97.8% were women and the median age at diagnosis was 53 years (range 12-87), 77.7% had limited cutaneous SSc (lcSSC), 19,3% patients had diffuse cutaneous SSc (dcSSC) and 2.9% had scleroderma sine scleroderma. The 67.5% of the patients were from a Mestizos or Amerindian ethnic group. Anti-RNA polymerase III was positive in 5.9% of the patients. In 36 patients, the anticentromere (ACA) and anti-Scl70 antibodies were negative; anti-RNA polymerase III was positive in 16.7% of these 36 patients. Pitting scars and pulmonary artery hypertension were more frequent in anti-RNA polymerase III positive patients who were also older at diagnosis. No association with gastric antral vascular ectasia was found. The only patient with scleroderma renal crisis was anti-RNA polymerase III positive.

CONCLUSIONS

Anti-RNA polymerase III frequency found in this study was one of the lowest reported, which could be related to the predominance of the Amerindian and Mestizo ethnic group. It is possible that the detection of anti RNA polymerase III allows better classification of SSc patients, to know their prognosis and to improve their follow-up, therefore more studies are needed.

The Ku complex: recent advances and emerging roles outside of non-homologous end-joining

Since its discovery in 1981, the Ku complex has been extensively studied under multiple cellular contexts, with most work focusing on Ku in terms of its essential role in non-homologous end-joining (NHEJ). In this process, Ku is well-known as the DNA-binding subunit for DNA-PK, which is central to the NHEJ repair process. However, in addition to the extensive study of Ku's role in DNA repair, Ku has also been implicated in various other cellular processes including transcription, the DNA damage response, DNA replication, telomere maintenance, and has since been studied in multiple contexts, growing into a multidisciplinary point of research across various fields. Some advances have been driven by clarification of Ku's structure, including the original Ku crystal structure and the more recent Ku-DNA-PKcs crystallography, cryogenic electron microscopy (cryoEM) studies, and the identification of various post-translational modifications. Here, we focus on the advances made in understanding the Ku heterodimer outside of non-homologous end-joining, and across a variety of model organisms. We explore unique structural and functional aspects, detail Ku expression, conservation, and essentiality in different species, discuss the evidence for its involvement in a diverse range of cellular functions, highlight Ku protein interactions and recent work concerning Ku-binding motifs, and finally, we summarize the clinical Ku-related research to date.

Anti-RNA Polymerase III Antibodies in Systemic Sclerosis: Multicentric Study from Argentina

OBJECTIVE

To describe the frequency of anti-RNA polymerase III antibody in patients with Systemic Sclerosis (SSc) of a group of healthcare centres from Argentina and to explore differences among patients with positive and negative anti-RNA polymerase III antibody.

PATIENTS AND METHODS

Data from clinical records, anamnesis and physical examination were collected from 135 patients with SSc (ACR/EULAR 2013). A serum sample from each patient was obtained for the detection of anti-RNA polymerase III IgG antibodies by ELISA.

RESULTS

In all, 97.8% were women and the median age at diagnosis was 53 years (range: 12-87), 77.7% had limited cutaneous SSc (lcSSC), 19,3% patients had diffuse cutaneous SSc (dcSSC) and 2.9% had scleroderma sine scleroderma. The 67.5% of the patients were from a Mestizos or Amerindian ethnic group. Anti-RNA polymerase III was positive in 5.9% of the patients. In 36 patients, the anticentromere (ACA) and anti-Scl70 antibodies were negative; anti-RNA polymerase III was positive in 16.7% of these 36 patients. Pitting scars and pulmonary artery hypertension were more frequent in anti-RNA polymerase III positive patients who were also older at diagnosis. No association with gastric antral vascular ectasia was found. The only patient with scleroderma renal crisis was anti-RNA polymerase III positive.

CONCLUSIONS

Anti-RNA polymerase III frequency found in this study was one of the lowest reported, which could be related to the predominance of the Amerindian and Mestizo ethnic group. It is possible that the detection of anti-RNA polymerase III allows better classification of SSc patients, to know their prognosis and to improve their follow-up, therefore more studies are needed.

Autoantibody profiles in systemic sclerosis; a comparison of diagnostic tests

OBJECTIVES

Autoimmune antibody profiling plays a prominent role in both classification and prognosis of systemic sclerosis (SSc). In the last years novel autoantibodies have been discovered and have become available in diagnostic assays. However, standardization in autoimmune serology is lacking, which may have a negative impact on the added value of autoantibodies in diagnosis and prognosis of SSc. In this paper we describe the comparison of commercially available diagnostic assays for the detection of SSc-associated autoantibodies and explored the coexistence of multiple SSc-associated autoantibodies within patients.

METHODS

Serum samples of 347 patients from the Nijmegen Systemic Sclerosis Cohort were included in this study. All patients fulfilled the ACR/EULAR 2013 classification criteria for SSc and were classified as DcSSc or LcSSc according to the Leroy and Medsger criteria. All samples were evaluated on standard laboratory diagnostic tests for detection of SSc-specific autoantibodies CENPA and CENPB (ACA), Scl-70 (ATA), RNA Polymerase III (rp11/155) (ARA), and SSc-associated autoantibodies Fibrillarin, Th-To, PM-scl75, PM-Scl100, RNP68/A/C, Ku, NOR90, and PDGFR from suppliers EUROIMMUN, D-tek and Thermo Fisher Scientific.

RESULTS

We found that 79% of the patients was positive for one or more of the SSc autoantibodies. Overall, a high agreement was observed between the diagnostic methods for the SSC-specific autoantibodies listed in the ACR/EULAR criteria (ATA, ACA, and ARA) (Cohen's kappa 0.53-0.97). However, a lower agreement was found for SSc-associated autoantibodies PM-Scl, and Ku, as well as for the SSc-specific autoantibodies fibrillarin and Th-To. Furthermore, the data revealed that the presence of ATA, ARA and ACA is predominantly mutually exclusive, with only a fraction of the patients testing positive for both ATA and ARA.

CONCLUSION

Our data showed high concordance of prevalent SSc-specific autoantibodies between different diagnostic assays. Further standardisation for low prevalent SSc-specific and SSc-associated autoantibodies is needed.

Characterization of Venezuelan Patients With Systemic Sclerosis: A Study in a Tertiary Hospital in Caracas

OBJECTIVE

The aim of the study was to investigate the demographic and clinical characteristics of Venezuelan patients with systemic sclerosis (SSc) seen in a tertiary hospital.

METHODS

Consecutive patients 18 years and older who fulfilled the 2013 ACR/EULAR classification criteria for SSc and who were followed up in the outpatient clinic of the Division of Rheumatology at the Hospital Universitario de Caracas were selected for the study. Demographic and clinical variables were registered at the time of inclusion using a standard protocol.

RESULTS

Forty-eight SSc patients were included; 46 (95.8%) were female; the mean age was 55.1±13.7 (mean±SD) years and all were of Hispanic ethnicity. Thirty-one (64.6%) had limited SSc and 17 (35.4%) had diffuse SSc. The mean duration of disease was 13.4±11.7 (mean±SD) years, 16.74±12.99 years for limited SSc and 7.52±5.25 years for diffuse SSc (p=0.0077). Raynaud's phenomenon was the most frequent manifestation (100%), followed by arthritis (68.8%), telangiectasia (60.4%), dyspnea (60.4%), dysphagia (58.3%) and puffy hands (56.3%). The modified Rodnan Skin Score (mRSS) and the frequency of dyspnea were higher in those with diffuse as compared to limited SSc (p=0.0211 and p=0.0003, respectively). We performed high-resolution computed tomography (HRCT) of the lungs in 31 patients; 14 (45.2%) had evidence of interstitial lung disease (ILD), 11 (68.8%) with diffuse SSc (p=0.0052). The most frequent anti-nuclear antibody pattern was nucleolar, accounting for 18 (42.8%) of the cases. Anti-centromere antibodies were present in 16.7% of the cases and were associated with the limited SSc subset (p=0.0443) and with calcinosis (p=0.0020). Anti-topoisomerase antibodies were associated with ILD (p=0.0077).

CONCLUSIONS

Typical clinical and serological manifestations were present in this sample of Venezuelan patients with SSc, with an expected distribution according to disease subtype. The autoantibody profile allows clinicians to identify those patients with limited forms of the disease and those without pulmonary involvement.

Characteristics of Systemic Sclerosis patients with positive anti-Th/To antibodies: About 6 patients and literature review

Among the antibodies described in Systemic Sclerosis (SSc), anti-Th/To antibodies (anti-Th/To) are rare and have been poorly studied. Thus, little is known about the profile of anti-Th/To positive patients. From our local Biobank (Marseille, France), we retrospectively selected data for 6 patients positive for anti-Th/To with an Immunodot assay. All of them suffered from SSc, sharing clinical and biological common features such as a limited cutaneous form of SSc, a decreased lung diffusing capacity and a speckled nuclear nucleolar immunofluorescence pattern of antinuclear antibodies screening on HEp-2 cells. In order to further characterize patients positive for anti-Th/To, we performed a thorough literature review. From 402 studied patients positive for anti-Th/To, we confirmed that these antibodies are associated with the limited cutaneous form of the disease (88% of the patients), and with an SSc related-pulmonary involvement (50%). The review analysis pointed out the rarity of the anti-Th/To with an estimated mean frequency of 3.4% of all SSc patients worldwide, their usual exclusivity with respect to the specific antibodies of scleroderma, and their high specificity (around 98%) for the diagnosis of SSc.

Clinical and serological profile of systemic sclerosis in Tunisia: A retrospective observational study

OBJECTIVE

The Prevalence of systemic sclerosis (SSc) and different clinical subsets varies across the world. Few data have been published on SSc patients in North Africa. Our objective was to describe a SSc cohort in south of Tunisia and to compare clinical findings, disease subsets and antibodies with other international SSc populations.

METHODS

In this retrospective observational study, Folders of patients with SSc seen in the internal medicine section of the Hedi Chaker Hospital between 2000 and 2013 were retrospectively analyzed. The diagnosis of SSc was retained according to ACR/EULAR 2013 criteria. Patients were classified into diffuse cutaneous SSc and limited cutaneous SSc subsets. Comparison with other cohorts was made based on published information.

RESULTS

A higher female: male ratio (8:1) and a higher diffuse subset prevalence (82%) was found in this Tunisian cohort comparing with others. We also found a lower prevalence of calcinosis and anticentromere antibodies. Within each subset, diffuse cutaneous and limited cutaneous scleroderma clinical findings were similar with other systemic sclerosis populations except for a very low prevalence in renal crisis and pulmonary hypertension. Our results indicate overlap syndrome defined as scleroderma associated with others connective tissue disorder's is a relatively common condition.

CONCLUSION

With slight variations, perhaps due to genetic, environmental or referral factors, SSc in this cohort appears to be similar to that described in other part of the world.

Clinical and laboratory features of African-Brazilian patients with systemic sclerosis

OBJECTIVE

African-Brazilians comprise a group of blacks and "pardos." As racial differences can be associated with distinct presentations, we evaluated the clinical and serological associations of African-Brazilians with systemic sclerosis (SSc).

METHODS

Sera from 260 adult SSc patients (203 whites and 57 African-Brazilians) were evaluated. Patients with overlap syndromes were excluded. Clinical and demographic data were obtained from an electronic register database. Laboratory analysis included the following: anti-CENP-A/CENP-B, Scl70, RNA polymerase III, Ku, fibrillarin, Th/To, PM-Scl75, and PM-Scl100 by line immunoassay and anti-nuclear antibodies (ANA) by indirect immunofluorescence (IIF) on HEp-2 cells.

RESULTS

African-Brazilian SSc patients presented shorter disease duration (12.8 ± 6.5 vs. 15.9 ± 8.1 years, p = 0.009), higher frequency of nucleolar ANA pattern (28% vs. 13%, p = 0.008), and lower frequencies of centromeric ANA pattern (14% vs. 29%, p = 0.026) and CENP-B (18% vs. 34%, p = 0.017), as well as an association with severe interstitial lung disease (58% vs. 43%; p = 0.044). Further comparison of ethnic groups according to subsets revealed that diffuse SSc African-Brazilian patients presented higher frequency of pulmonary hypertension (p = 0.017), heart involvement (p = 0.037), nucleolar ANA pattern (p = 0.036), anti-fibrillarin antibodies (p = 0.037), and higher mortality (48% vs. 19%; p = 0.009). A different pattern was observed for the limited subset with solely a lower frequency of esophageal involvement (p = 0.050) and centromeric ANA pattern (p = 0.049). Survival analysis showed that African-Brazilians had a higher mortality, when adjusted for age, gender, and clinical subset (RR 2.06, CI 95% 1.10-3.83, p = 0.023).

CONCLUSION

African-Brazilians have distinct characteristics according to clinical subset and an overall more severe SSc than whites, similar to the blacks from other countries.Key Points • African-Brazilian SSc patients were associated with severe interstitial lung disease and nucleolar ANA pattern when compared to white SSc patients. • When disease subsets were considered, African-Brazilian patients with diffuse SSc presented association with pulmonary hypertension, heart involvement, nucleolar ANA pattern, and anti-fibrillarin antibodies. • White SSc patients were associated with centromeric ANA pattern. • Survival analysis at 5, 10, 15, and 20 years, adjusted for age, gender, and disease subset, was significantly worse in African-Brazilian SSc patients.

Prevalence of auto-antibodies associated to pulmonary arterial hypertension in scleroderma - A review

The prevalence of auto-antibodies associated to pulmonary arterial hypertension in scleroderma patients was reviewed, based on reports cited in two major scientific databases. Data were collected on the following types of antibodies: antinuclear, anti-double-stranded DNA, anticentromere, anti-CENP-A, anti-CENP-B, anti-bicaudal D2, anti-nucleolar, anti-Scl-70 (anti-topoisomerase I), anti-topoisomerase II α, anti-RNP, anti-U1RNP, anti-U3RNP, anti-RNA polymerase III, anti-Th/To, anti-histone, antiphospholipid, anti-PmScl, anti-Sm, anti SSA (anti-Ro),anti SSB (La), anti-Ro52 (TRIM 21), anti-Ku, anti-B23, anti-RuvBL1, anti-RuvBL2, anti-fibrin bound tissue plasminogen activator, anti-endothelial cell, anti-phosphatidylserine-prothrombin complex, anti-endothelin-1 type A receptor, anti-angiotensin II type 1 receptor, anti‑carbonic anhydrase II, anti-fibroblast, anti-cyclic citrullinated peptide, anti-4-sulfated N-Acetyl-lactosamine, class I and II anti-human leukocyte antigen. Auto-antibodies were shown by different authors to be associated to this condition, with different prevalence values for each type of auto-antibody. Antinuclear antibodies, anti-centromere antibodies, antiphospholipid antibodies, anti-U3 RNP antibodies and anti-Th/To antibodies would appear to show a particularly important prevalence in scleroderma patients with pulmonary hypertension, appearing in about 8/10 (antinuclear), 1/ 2 (anti-centromere, anti-phospholipid), and 1/4 (anti-U3RNP, anti-Th/To) of patients. The available evidence points in the direction of a strong association between auto-immune mechanisms and pulmonary hypertension in the setting of scleroderma.

Multiparametric autoantibody profiling of patients with systemic sclerosis in Greece

Background:

Systemic sclerosis (SSc) is an autoimmune rheumatic disease characterized by a wide range of disease-specific and disease-related autoantibodies (autoAbs). Profile assays have been developed and are currently in use to meet the demand for better characterization of all autoAbs found in SSc patients.

Aim:

To assess the clinical relevance of SSc-related autoantibodies in 158 patients with SSc, all from Central Greece, taking advantage of a multiparametric SSc autoantibody line immunoassay.

Material and methods:

158 consecutive patients with SSc (137 females, mean age 53.2 ± 10 years; 63 patients with dcSSc and 95 with lcSSc) from central Greece were included in the study. Eighteen patients with morphea were also included. Serum samples were analyzed by a profile SSc nucleoli line assay (Euroimmun) to detect Abs against 13 autoantigens: Scl-70, Centromere (A, B), RNA polymerase III (subunits 11 & 155), fibrillarin, NOR90, Th/To, PM/Scl 100, PM/Scl75, Ku, PDGFR and Ro52. Antinuclear autoAbs (ANAs) were detected by indirect immunofluorescence.

Results:

ANAs were detected in 97.5% of SSc patients. Reactivities to specific autoantigens were as follows: Topo I, 40.5%; CENP, 32.9%; Ro52, 21.5%; RP11, 8.9%; RP155, 13.3%; NOR 90, 4.4%; Ku 3.8%; PM-Scl75, 3.2%; PM-Scl100, 1.3%; Th/To, 1.3%; Fibrillarin, 1.3%; PDGFR 0%; Ro52 21.5%. Twenty-one of SSc did not have any of the main autoAbs, namely anti-Topo I, anti-CENP, anti-RNA pol III Abs.

Conclusions:

Multiparametric autoAb test provides positive SSc-associated autoAb reactivities in SSc patients negative for the three main autoAbs and this may prove of significance in early disease diagnosis.

Consensus best practice pathway of the UK Systemic Sclerosis Study group: management of cardiac disease in systemic sclerosis

Objective

Cardiac disease in SSc can manifest in various ways and is associated with a poor prognosis. There is little evidence on how best to detect and manage cardiac disease in SSc. Our objective was to produce an expert consensus best practice pathway for the management of cardiac disease in SSc.

Methods

The UK Systemic Sclerosis Study Group set up several working groups to develop a number of consensus best practice pathways for the management of SSc-specific complications, including cardiac disease. A multidisciplinary task force was convened. The guidelines were partly informed by a comprehensive literature review.

Results

A best practice pathway for cardiac disease (with a focus on primary cardiac disease) in SSc is presented, including approaches for early detection and standard pharmacological and device therapies. Due to the benefits, shared care and a multidisciplinary approach are recommended. A future research agenda has been formulated in response to the relative lack of understanding of the natural history of primary cardiac disease that was highlighted by the initiative.

Conclusion

The physician should be alert to the possibility of cardiac disease in SSc; it is best managed within a multidisciplinary team including both rheumatologists and cardiologists. This pathway provides a reference for all physicians managing patients with SSc.

Ethnic Differences in Autoantibody Diversity and Hierarchy: More Clues from a US Cohort of Patients with Systemic Sclerosis

OBJECTIVE

To determine the autoantibody repertoire and clinical associations in a multiethnic cohort of American patients with systemic sclerosis (SSc).

METHODS

There were 1000 patients with SSc (196 Hispanic, 228 African American, 555 white, and 21 other) who were screened for antinuclear antibodies (ANA), including anticentromere antibodies (ACA) by indirect immunofluorescence assay, antitopoisomerase-1 (topo-1/Scl-70) by immunodiffusion, and anti-RNA polymerase III (RNAP III) by ELISA. Sera from 160 patients with mainly nucleolar and/or speckled ANA pattern, but negative for ACA, Scl-70, and RNAP III, were further characterized by immunoprecipitation for SSc-specific antibodies.

RESULTS

The prevalence of antibodies against RNAP III, Th/To, and PM/Scl did not differ significantly among the ethnic groups. The frequency of anti-Scl-70 was lowest in whites (18.0%) compared with 24.0% and 26.8% in Hispanics and African Americans (p = 0.01), respectively. Compared with African American patients, Hispanic and white subjects had a higher frequency of ACA (p < 0.0001) and lower frequency of U3-RNP (p < 0.0001). U3-RNP antibodies were uniquely higher in African American patients, independent of clinical subset, while Th/To autoantibodies were associated with limited cutaneous SSc in white subjects. Overall, Hispanic and African American patients had an earlier age of onset and a predominance of diffuse cutaneous SSc compared with their white counterparts.

CONCLUSION

SSc-specific antibodies may predict disease subset; however, the hierarchy of their prevalence differs across ethnic groups. This study provides the most extensive analysis to date on the relevance of autoantibodies in the diagnosis and clinical manifestations of SSc in Hispanic American patients.

Single-specificity anti-Ku antibodies in an international cohort of 2140 systemic sclerosis subjects: clinical associations

Autoantibodies directed against the Ku autoantigen are present in systemic sclerosis (SSc) and have been associated with myositis overlap and interstitial lung disease (ILD). However, there is a paucity of data on the clinical correlates of anti-Ku antibodies in the absence of other SSc-specific antibodies. The aim of this study was to assess the clinical correlates of single-specificity anti-Ku in SSc.An international (Canada, Australia, USA, Mexico) cohort of 2140 SSc subjects was formed, demographic and clinical variables were harmonized, and sera were tested for anti-Ku using a line immunoassay. Associations between single-specificity anti-Ku antibodies (i.e., in isolation of other SSc-specific antibodies) and outcomes of interest, including myositis, ILD, and survival, were investigated.Twenty-four (1.1%) subjects had antibodies against Ku, and 13 (0.6%) had single-specificity anti-Ku antibodies. Subjects with single-specificity anti-Ku antibodies were more likely to have ILD (58% vs 34%), and to have increased creatine kinase levels (>3× normal) at baseline (11% vs 1%) and during follow-up (10% vs 2%). No difference in survival was noted in subjects with and without single-specificity anti-Ku antibodies.This is the largest cohort to date focusing on the prevalence and disease characteristics of single-specificity anti-Ku antibodies in subjects with SSc. These results need to be interpreted with caution in light of the small sample. International collaboration is key to understanding the clinical correlates of uncommon serological profiles in SSc.

Angiotensin II Type 1 receptor (AGTR1) gene polymorphisms are associated with vascular manifestations in patients with systemic sclerosis (SSc)

INTRODUCTION

Systemic sclerosis (SSc) shows variable clinical expression in different ethnic groups; vascular abnormalities are a prominent feature of this disease and its clinical expression may be influenced by genetic factors.

PATIENTS AND METHODS

Herein, we describe 15 polymorphisms of the renin-angiotensin-aldosterone pathway in 170 Mexican admixed SSc patients (defined as patients with Mexican ancestry for at least 3 generations) and 199 healthy controls. We determined the presence of angiotensin II Type 1 receptor (AGTR1), angiotensin converting enzyme (ACE) and Endothelin 1 single nucleotide polymorphisms (SNPs) using 5' exonuclease TaqMan genotyping assays on a 7900HT real-time fast polymerase chain reaction (PCR) system.

RESULTS

These polymorphisms had a similar distribution between SSc patients and controls, but we found that the AGTR1 G-680T (rs275652) (p = 0.02; OR 3.5; 95%CI 1.2-10.4) and AGTR1 A-119G (rs275653) (p = 0.008; OR 4.2; 95% CI 1.5-12.1) polymorphisms were associated with severe vascular involvement in our SSc patients.

CONCLUSIONS

This is the first report of the association of these polymorphisms with vasculopathy in Mexican admixed SSc patients. Our findings suggested that the angiotensin II Type 1 receptor genotype may influence the clinical expression of vasculopathy in these patients. Functional analyses should follow.

Interpretation of an Extended Autoantibody Profile in a Well-Characterized Australian Systemic Sclerosis (Scleroderma) Cohort Using Principal Components Analysis

OBJECTIVE

To determine the relationships between systemic sclerosis (SSc)-related autoantibodies, as well as their clinical associations, in a well-characterized Australian patient cohort.

METHODS

Serum from 505 Australian SSc patients were analyzed with a commercial line immunoassay (EuroLine; Euroimmun) for autoantibodies to centromere proteins CENP-A and CENP-B, RNA polymerase III (RNAP III; epitopes 11 and 155), the 90-kd nucleolar protein NOR-90, fibrillarin, Th/To, PM/Scl-75, PM/Scl-100, Ku, topoisomerase I (topo I), tripartite motif-containing protein 21/Ro 52, and platelet-derived growth factor receptor. Patient subgroups were identified by hierarchical clustering of the first 2 dimensions of a principal components analysis of quantitative autoantibody scores. Results were compared with detailed clinical data.

RESULTS

A total of 449 of the 505 patients were positive for at least 1 autoantibody by immunoblotting. Heatmap visualization of autoantibody scores, along with principal components analysis clustering, demonstrated strong, mutually exclusive relationships between CENP, RNAP III, and topo I. Five patient clusters were identified: CENP, RNAP III strong, RNAP III weak, topo I, and other. Clinical features associated with CENP, RNAP III, and topo I were consistent with previously published reports concerning limited cutaneous and diffuse cutaneous SSc. A novel finding was the statistical separation of RNAP III into 2 clusters. Patients in the RNAP III strong cluster had an increased risk of gastric antral vascular ectasia, but a lower risk of esophageal dysmotility. Patients in the other cluster were more likely to be male and to have a history of smoking and a history of malignancy, but were less likely to have telangiectasia, Raynaud's phenomenon, and joint contractures.

CONCLUSION

Five major autoantibody clusters with specific clinical and serologic associations were identified in Australian SSc patients. Subclassification and disease stratification using autoantibodies may have clinical utility, particularly in early disease.

Scleroderma: the role of serum autoantibodies in defining specific clinical phenotypes and organ system involvement

PURPOSE OF REVIEW

To discuss recent advances in serologic testing for systemic sclerosis (SSc)-associated antibodies with respect to the diagnosis and prognosis of the disease.

RECENT FINDINGS

The importance of SSc antibodies for diagnosis has become increasingly recognized, as evidenced by incorporation into the 2013 American College of Rheumatology/the European League Against Rheumatism clinical classification criteria for SSc. Two new SSc-associated antibodies and their clinical associations have been described. Multiple cohort studies have reported variable antibody frequency distribution based on geography, but the clinical associations remain much the same. New associations include anti-RNA polymerase III antibodies with gastric antral vascular ectasia, and a temporal association between SSc onset and RNA polymerase III antibodies.

SUMMARY

The role and associations of SSc-associated antibodies for diagnosis and internal organ involvement are becoming increasingly accepted.

HLA Class I and II Blocks Are Associated to Susceptibility, Clinical Subtypes and Autoantibodies in Mexican Systemic Sclerosis (SSc) Patients

INTRODUCTION

Human leukocyte antigen (HLA) polymorphism studies in Systemic Sclerosis (SSc) have yielded variable results. These studies need to consider the genetic admixture of the studied population. Here we used our previously reported definition of genetic admixture of Mexicans using HLA class I and II DNA blocks to map genetic susceptibility to develop SSc and its complications.

METHODS

We included 159 patients from a cohort of Mexican Mestizo SSc patients. We performed clinical evaluation, obtained SSc-associated antibodies, and determined HLA class I and class II alleles using sequence-based, high-resolution techniques to evaluate the contribution of these genes to SSc susceptibility, their correlation with the clinical and autoantibody profile and the prevalence of Amerindian, Caucasian and African alleles, blocks and haplotypes in this population.

RESULTS

Our study revealed that class I block HLA-C*12:03-B*18:01 was important to map susceptibility to diffuse cutaneous (dc) SSc, HLA-C*07:01-B*08:01 block to map the susceptibility role of HLA-B*08:01 to develop SSc, and the C*07:02-B*39:05 and C*07:02-B*39:06 blocks to map the protective role of C*07:02 in SSc. We also confirmed previous associations of HLA-DRB1*11:04 and -DRB1*01 to susceptibility to develop SSc. Importantly, we mapped the protective role of DQB1*03:01 using three Amerindian blocks. We also found a significant association for the presence of anti-Topoisomerase I antibody with HLA-DQB1*04:02, present in an Amerindian block (DRB1*08:02-DQB1*04:02), and we found several alleles associated to internal organ damage. The admixture estimations revealed a lower proportion of the Amerindian genetic component among SSc patients.

CONCLUSION

This is the first report of the diversity of HLA class I and II alleles and haplotypes Mexican patients with SSc. Our findings suggest that HLA class I and class II genes contribute to the protection and susceptibility to develop SSc and its different clinical presentations as well as different autoantibody profiles in Mexicans.

Increased incidence of Sjogren's syndrome in systemic sclerosis: A nationwide population study

In the past, there were no studies to evaluate the incidence of Sjogren's syndrome and its relationship with sex and age in patients with systemic sclerosis. In this study, we enrolled 2217 patients with systemic sclerosis and 6485 controls from Taiwan's Registry of Catastrophic Illness database and National Health Insurance Research Database. Every patient with systemic sclerosis was matched to at most three controls by sex, age, month, and year of first diagnosis of systemic sclerosis. Standardized incidence ratio (SIR) of Sjogren's syndrome in patients with systemic sclerosis and 95% confidence interval (95% CI) were calculated. Cox hazard regression was used to calculate the hazard ratio (HR). Both male and female patients with systemic sclerosis had higher incidences of Sjogren's syndrome (SIR: 7.59, 95% CI = 2.97-19.51; SIR: 7.59, 95% CI = 5.56-10.42, respectively). The incidence of Sjogren's syndrome in patients with systemic sclerosis was still higher compared with control when stratified according to age. Age at diagnosis of Sjogren's syndrome was earlier in patients with systemic sclerosis in both male and female groups (p = 0.018; p < 0.001, respectively). Systemic sclerosis was associated with Sjogren's syndrome after adjusting for age, sex, and various autoimmune diseases (HR: 5.98, 95% CI = 4.79-7.47, p < 0.001). Common cytokines, overlapping antibodies, and similar risk alleles were all potential causes of increased incidence of Sjogren's syndrome in systemic sclerosis.

Prevalence of anti-RNA polymerase III antibodies in systemic sclerosis: New data from a French cohort and a systematic review and meta-analysis

OBJECTIVE

Studies assessing the prevalence of anti-RNA polymerase III (anti-RNAP III) antibodies in systemic sclerosis (SSc) have yielded a wide range of results. The aim of the present study was to describe a new SSc cohort tested for presence of anti-RNAP III and perform a systematic review and meta-analysis to assess the prevalence of anti-RNAP III in patients worldwide and the potential factors of variability.

METHODS

Seropositivity for anti-RNAP III was evaluated in a French cohort of SSc patients. A systematic review of the literature was carried out in PubMed and EMBase. Meta-analysis was performed using available data on prevalence, clinical characteristics of SSc patients, and the types of assays used for anti-RNAP III testing.

RESULTS

One hundred thirty-three French SSc patients were tested for anti-RNAP III, and a prevalence of 6-9% was found in these patients. Thirty studies representing a total population of 8,437 SSc patients were included in the meta-analysis. Prevalence of anti-RNAP III in this population was highly variable (range 0-41%). The overall pooled prevalence of anti-RNAP III was 11% (95% confidence interval 8-14), but heterogeneity was high among studies (I(2) = 93%, P < 0.0001). Geographic factors such as continent or country of study origin partially explained this heterogeneity and correlated with the prevalence. No other baseline SSc characteristics were significantly correlated with the prevalence of anti-RNAP III.

CONCLUSION

Data on our new cohort and our meta-analysis of the literature confirmed that anti-RNAP III prevalence in SSc varies among centers. Geographic factors were significantly associated with prevalence, which underscores the probable implication that genetic background and environmental factors play a role. Heterogeneity among studies remained largely unexplained.

The long-term marriage between autoimmunity and internal medicine: a homage to Manuel Carlos Dias

Our understanding of autoimmune diseases results from the perfect combination of basic and clinical scientific research, and the figure that is closest to the proposed autoimmunology specialist is certainly the internist. The role of B cells in rheumatoid arthritis, the immunological mechanisms to fibrosis or to tissue specific damage, the classification of Bechet's syndrome, the clinical outcomes of antiphospholid syndrome, and new biomarkers for vascular complications in systemic sclerosis constitute, among others, are ideal examples of this combination. For these reason, this issue includes comprehensive reviews in all these areas and is dedicated to Dr. Manuel Carlos Dias and his career in the perfectioning and teaching of the clinical skills necessary to manage autoimmune disease. We are convinced that these discussions are likely of interest to basic scientists and clinicians alike for the proposed translational applications.

New centromere autoantigens identified in systemic sclerosis using centromere protein microarrays

OBJECTIVE

To identify novel centromere protein (CENP) targets of anticentromere antibodies (ACA), and to investigate their association with clinical manifestations of systemic sclerosis (SSc).

METHODS

A CENP-focused protein microarray was fabricated by spotting 14 purified CENP. These microarrays were individually incubated with 35 ACA-positive SSc sera and 20 ACA-negative healthy control samples. Newly identified CENP autoantigens with high sensitivities were selected for validation and characterization.

RESULTS

Statistical analysis revealed 11 CENP are potential target antigens of ACA in patients with SSc. Of them, 5 [CENP-P, CENP-Q, CENP-M (isoform I), CENP-J, and CENP-T] are novel, among which CENP-P and CENP-Q showed high sensitivities in ACA-positive SSc sera of 34.3% and 28.6%, respectively. Subsequently, 186 SSc sera (35 ACA-positives and 151 negatives), 69 ACA-positive sera from other various autoimmune diseases (primary Sjögren syndrome, systemic lupus erythematosus, rheumatoid arthritis, and primary biliary cirrhosis), and 31 healthy sera were assayed for the presence of anti-CENP-P and -Q autoantibodies by ELISA followed by Western blotting analysis. CENP-P and -Q autoantibodies were detected in ACA-positive sera of various disease groups; among them, SSc showed the highest detection rate. Anti-CENP-P was also found in 9 of the 151 ACA-negative sera. Analyses of the correlation with clinical information showed anti-CENP-P-positive patients had higher levels of IgG, IgA, and erythrocyte sedimentation rate among the ACA-positive cohort and were more vulnerable to renal disease in the ACA-negative patients with SSc. Regardless of ACA status, anti-CENP-P or Q-negative patients seem to be predominantly affected by interstitial lung disease.

CONCLUSION

CENP-P and CENP-Q were identified as novel ACA autoantigens by CENP microarray assays followed by validation of ELISA and Western blotting. Both of them have prognostic utility for interstitial lung disease. CENP-P was associated with renal disease in an ACA-negative cohort.

Autoimmunity in 2011

The mechanisms leading to the onset and perpetuation of systemic and tissue-specific autoimmune diseases are complex, and numerous hypotheses have been proposed or confirmed over the past 12 months. It is particularly of note that the number of articles published during 2011 in the major immunology and autoimmunity journals increased by 3 % compared to the previous year. The present article is dedicated to a brief review of the reported data and, albeit not comprehensive of all articles, is aimed at identifying common and future themes. First, clinical researchers were particularly dedicated to defining refractory forms of diseases and to discuss the use and switch of therapeutic monoclonal antibodies in everyday practice. Second, following the plethora of genome-wide association studies reported in most multifactorial diseases, it became clear that genomics cannot fully explain the individual susceptibility and additional environmental or epigenetic factors are necessary. Both these components were widely investigated, both in organ-specific (i.e., type 1 diabetes) and systemic (i.e., systemic lupus erythematosus) diseases. Third, a large number of 2011 works published in the autoimmunity area are dedicated to dissect pathogenetic mechanisms of tolerance breakdown in general or in specific conditions. While our understanding of T regulatory and Th17 cells has significantly increased in 2011, it is of note that most of the proposed lines of evidence identify potential targets for future treatments and should not be overlooked.