Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Scleroderma, Diffuse”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 523 records · Page 29Linked to original sources

Proton magnetic resonance spectroscopy reveals central neuroaxonal impairment in systemic sclerosis.

OBJECTIVE: . Involvement of the central nervous system (CNS) in systemic sclerosis (SSc) is rare. Proton magnetic resonance spectroscopy (1H-MRS) assesses in vivo cerebral metabolites. We investigated the biochemical modifications of the CNS in SSc. METHODS: N-acetylaspartate/creatine ratio (NAA/Cr) and choline/creatine ratio (Cho/Cr) at right centrum semiovale (RCS) and at right basal ganglia (RBG) were evaluated by 1H-MRS in 12 patients with limited (lSSc) and 8 patients with diffuse SSc (dSSc) and 20 control subjects. RESULTS: With 1H-MRS, a significant reduction of NAA/Cr ratio at RBG (p < 0.02) and at RCS (p < 0.002) was detected in SSc patients. Cho/Cr ratio was increased (p < 0.02) in the RCS, but not in RBG. In patients with lSSc, a significant reduction of NAA/Cr was detected in RCS but not in RBG. CONCLUSION: Evidence of neuroaxonal damage strongly suggests the existence of CNS involvement in SSc.

Adult↗

Serum pulmonary and activation-regulated chemokine/CCL18 levels in patients with systemic sclerosis: a sensitive indicator of active pulmonary fibrosis.

OBJECTIVE: To clarify the clinical significance of serum levels of pulmonary and activation-regulated chemokine (PARC) in the diagnosis and monitoring of pulmonary fibrosis (PF) in patients with systemic sclerosis (SSc) and to compare PARC levels with KL-6 antigen or surfactant protein D (SP-D) levels. METHODS: Serum PARC levels were determined by enzyme-linked immunosorbent assay in 123 SSc patients. In a retrospective longitudinal study, correlation of serum PARC levels with the activity of PF was assessed in 21 SSc patients with active PF. RESULTS: PARC levels at the first visit were higher in patients with SSc than in patients with systemic lupus erythematosus (SLE) or healthy controls. Increased serum PARC levels were associated with involvement of PF, decreased diffusing capacity for carbon monoxide, and decreased vital capacity in SSc patients. In the longitudinal study, serum PARC levels were significantly decreased in SSc patients with inactive PF compared with those with active PF. CONCLUSION: Elevated serum PARC levels correlated with PF and more sensitively reflected the PF activity than did serum KL-6 or SP-D levels in SSc. Serum PARC levels may be a useful new serum marker for active PF in SSc.

Antigens↗

The efficacy of self-administered stretching for finger joint motion in Japanese patients with systemic sclerosis.

OBJECTIVE: To determine the efficacy of self-administered stretching of each finger in Japanese patients with systemic sclerosis (SSc). METHODS: Forty-five patients with SSc (32 with diffuse cutaneous SSc and 13 with limited cutaneous SSc) were given instructions on self-administered stretching and were directed to perform it every day. Individual fingers were maintained in a stretched position using the opposite hand for 10 seconds and this was repeated 3-10 times. To evaluate the effect of the stretching program, finger passive range of motion (ROM) was assessed using a goniometer on the first visit and after 1 month and 1 year of the stretching program. The Health Assessment Questionnaire (HAQ) was also assessed on the first visit and 1 year afterward. RESULTS: The total passive ROM was significantly improved in each finger after 1 month of finger stretching. The total passive ROM was further improved or maintained within 1 year after the first visit. Although ROM was less in patients with diffuse cutaneous SSc than in those with limited cutaneous SSc at the first visit, ROM increased significantly irrespective of disease duration or severity of skin sclerosis. Finger stretching may improve the finger function, since the HAQ score for hand functions such as eating and gripping was significantly decreased. CONCLUSION: Our original self-administered stretching program may be useful for improving finger joint motion in patients with SSc; future studies in various ethnic populations will be needed to determine the universal efficacy of this method.

Female↗

Anti-endothelial cell antibodies from patients with limited cutaneous systemic sclerosis bind to centromeric protein B (CENP-B).

By using a quantitative immunoblotting technique on protein extracts of human macrovascular and microvascular endothelial cells, we have analyzed the self-reactive repertoires of IgG from 20 patients with limited cutaneous SSc, 40 patients with diffuse SSc and 60 age- and sex-matched healthy controls. Serum IgG from 15/20 patients with limited cutaneous SSc and anti-centromere antibodies bound to at least one of the two 75- and 85-kDa protein bands in the different endothelial cell extracts, whereas IgG from healthy controls or patients with diffuse SSc did not. N-terminal sequencing of the 75- and 85-kDa bands identified CENP-B as the sole antigen in both bands. Moreover, IgG from all of the SSc patients who recognized the 75- and/or 85-kDa bands bound to a full-length recombinant CENP-B protein as assessed by ELISA, whereas IgG from other SSc patients did not. The main target of anti-endothelial cell antibodies in patients with limited cutaneous SSc is the nuclear and ubiquitous protein CENP-B.

Antibody Specificity↗

A novel autoantigen to differentiate limited cutaneous systemic sclerosis from diffuse cutaneous systemic sclerosis: the interferon-inducible gene IFI16.

OBJECTIVE: To investigate the presence and clinical significance of autoantibodies against the interferon-inducible gene IFI16 in systemic sclerosis (SSc), systemic lupus erythematosus (SLE), and other autoimmune diseases. METHODS: Immunohistochemical analysis was used to evaluate the expression of IFI16 in skin biopsy specimens obtained from patients with SSc and patients with SLE. Levels of antibodies against IFI16 in sera from 82 patients with SSc and 100 patients with SLE were determined by enzyme-linked immunosorbent assay. Other autoimmune diseases such as primary Sjögren's syndrome (SS), rheumatoid arthritis (RA), chronic urticaria, and hepatitis C virus (HCV) infection were also examined. RESULTS: Expression of IFI16 was greatly increased and was ubiquitous in all layers of the epidermis and in the dermal inflammatory infiltrates of lesional skin from both patients with SLE and patients with SSc. Patients with SLE, those with primary SS, and those with SSc exhibited significantly higher anti-IFI16 IgG antibody levels compared with normal controls (for SLE, P < 0.002; for primary SS, P < 0.001; for SSc, P < 0.0005). Anti-IFI16 titers above the ninety-fifth percentile for control subjects were observed in 26% of the patients with SLE, 50% of those with primary SS, and 21% of those with SSc (28% of patients with limited cutaneous SSc [lcSSc] versus 4% of patients with diffuse cutaneous SSc [dcSSc]). In contrast, the prevalence of anti-IFI16 was 4% in patients with RA, 5% in those with chronic urticaria, and 13% in those with HCV infection. CONCLUSION: The results of this study provide evidence that an IFN-inducible gene, IFI16, may be involved in the pathophysiologic mechanisms of connective tissue disorders such as SSc. Moreover, a strict correlation with lcSSc was also demonstrated, thus providing a novel tool in the differential diagnosis of lcSSc from dcSSc.

Adult↗

Low-dose intravenous cyclophosphamide in systemic sclerosis: an open prospective efficacy study in patients with early diffuse disease.

OBJECTIVE: To investigate the efficacy of a treatment with low-dose intravenous cyclophosphamide (CYC) and low-dose prednisone in early diffuse cutaneous systemic sclerosis (dcSSc). METHODS: Patients with dcSSc and a disease duration <24 months consecutively admitted to a tertiary centre underwent a prospective 1-year study. They were treated with i.v. CYC 500 mg/pulses, 10 mg prednisone equivalent, and supportive therapy. Modified Rodnan skin score (mRss), Health Assessment Questionnaire-Disability Index (HAQ-DI), forced vital capacity (FVC), and diffusing lung capacity for CO (DLCO) were assessed as outcome measures. In addition, the nine Medsger severity scale scores were evaluated. RESULTS: mRss and DLCO significantly improved at both 6 (p = 0.002 and 0.012, respectively) and 12 months (p = 0.002 and 0.003, respectively). HAQ-DI showed a nearly significant reduction at 12 months (p = 0.06). Medsger's severity scores also improved for general condition (p = 0.001), peripheral vascular (p = 0.05), skin (p = 0.02), joint/tendon (p = 0.001), muscle (p = 0.05), and lung (p = 0.02). No treatment interruption was needed. CONCLUSIONS: This preliminary study suggests a role for low-dose i.v. CYC in the treatment of early dcSSc. Controlled studies are warranted.

Adult↗

Morbidity and mortality of patients diagnosed with systemic sclerosis after the age of 75: a nested case-control study.

This study aims to characterize the clinical features of a cohort of patients diagnosed with systemic sclerosis (SSc) after the age of 75 and compare them to a group diagnosed at a younger age. We record the review of 769 patients diagnosed with SSc over the past 16 years. Utilizing a nested case-control model, we compare demographics, disease severity, morbidity, and mortality data of all patients diagnosed after the age of 75 to sex- and disease-type-matched, randomly selected group of patients diagnosed with SSc before the age of 60. Twelve patients were diagnosed with SSc after the age of 75, seven with the diffuse, and five with the limited form. It took longer to diagnose SSc in the older patients, and comparison of disease severity revealed a worse pulmonary picture and a more frequent development of malignancy in the older patients as compared with the younger ones. During a mean follow-up of 36.2 months, our cohort of patients did not have worsening in their disease severity, though 6 months after the last follow-up, six patients died. We conclude that a diagnosis of SSc at an older age appears to be a poor prognostic indicator related to both disease severity and comorbidities. A higher clinical suspicion will lead to an earlier diagnosis and a potential decrease in morbidity and mortality.

Aged↗

[Interstitial lung disease in systemic sclerosis].

Interstitial lung diseases (ILD) associated with systemic sclerosis (SSc) are mainly encountered in patients with diffuse disease, although they may also be seen in patients with limited cutaneous SSc. ILD screening must be performed regularly, with high-resolution computed tomography and pulmonary function tests (TLCO). Up to 75% of patients with diffuse SSc develop a form of ILD. ILD remains stable in most patients and does not worsen. The nonspecific nature of SSc-associated ILD makes it different from idiopathic ILD and helps to explain its better prognosis. Nonetheless, ILD is one of the two leading causes of death in SSc patients. Treatment of SSc-associated ILD is not yet well codified. Antifibrotic treatments have not proved beneficial, and the efficacy of cyclophosphamide, which has been used to treat this condition for 15 years, has been shown to be very limited against SSc-associated ILD. A subgroup of patients with rapidly progressive ILD might benefit from intravenous cyclophosphamide pulses in association with 15 mg/d prednisone.

Anti-Inflammatory Agents↗

Augmented production of transforming growth factor-beta by cultured peripheral blood mononuclear cells from patients with systemic sclerosis.

We sought to determine whether the spontaneous production of transforming growth factor-beta (TGF-beta) by peripheral blood mononuclear cells (PBMC) is increased in patients with systemic sclerosis (SSc). Culture supernatants of PBMC from SSc patients (n = 88) and healthy controls (n = 44) were analyzed by enzyme-linked immunosorbent assay. The production of active TGF-beta1 and total (active and latent) TGF-beta1 by PBMC from patients with limited cutaneous SSc (lSSc) and by PBMC from patients with diffuse cutaneous SSc (dSSc) was significantly elevated compared to the production by PBMC from normal controls. Production of active TGF-beta1 by dSSc PBMC was higher than that by lSSc PBMC, although not significantly. Patients with PBMC with increased active or total TGF-beta1 production showed significantly shorter disease duration than patients with PBMC with normal production levels. PBMC from patients without anticentromere antibody showed enhanced active TGF-beta1 production more frequently than those from patients with anticentromere antibody. PBMC from SSc patients more frequently showed enhanced total TGF-beta2 production than PBMC from normal controls. Among each leukocyte subset, spontaneous production of total TGF-beta1 was significantly higher in cultured peripheral monocytes/macrophages, but not in T cells, B cells, or NK cells, from patients than from normal controls. Thus, the enhanced production of TGF-beta by PBMC may contribute to the disease process in SSc

Adult↗

Prevalence of systemic sclerosis in a French multi-ethnic county.

OBJECTIVE: To assess the prevalence of systemic sclerosis (SSc) in a French multi-ethnic population and to examine ethnic differences. METHODS: This survey was conducted in Seine-Saint-Denis County, a suburb of Paris, home to 1,094,412 adults (>/=15 yr), among whom 26% are of non-European background with mainly northern and sub-Saharan African, Asian and Caribbean ancestries. The study period comprised the entire calendar year 2001. Patients were ascertained through four sources: public and private hospitals, general practitioners and community specialists, the French SSc patient support group, and the National Public Health Insurance System database. Only cases meeting either the 1980 ACR and/or LeRoy and Medsger's classification criteria were included and assigned to three clinical subsets: limited (normal skin) (l), limited cutaneous (lc) or diffuse cutaneous (dc) SSc. Capture-recapture (CR) analyses using log-linear modelling were performed to correct for incomplete case finding. RESULTS: We retained a total of 119 patients with SSc, including 15 extrapolated from inaccessible files. CR analysis estimated that 54.2 additional cases were missed by all the sources. The overall SSc prevalence (per million adults) was 158.3 (95% confidence interval, 129-187); those of lSSc, lcSSc and dcSSc were, respectively, 32.3 (16-48), 83.1 (66-101) and 42.9 (25-60); and respective values for Europeans and non-Europeans were 140.2 (112-170) and 210.8 (128-293). CONCLUSION: Regarding the heterogeneity of previously published estimates, this population-based survey using CR analysis might contribute to obtaining a better appraisal of SSc prevalence. Despite overlapping confidence intervals, the higher prevalence observed for non-Europeans could support potential influences of ethnic origin on the pathogenesis of SSc.

Adult↗

Aortic stiffness in systemic sclerosis is increased independently of the extent of skin involvement.

OBJECTIVE: To study the stiffness of large arteries in relation to the extent of skin and lung fibrosis, aortic distensibility was examined in patients with diffuse and limited systemic sclerosis (SSc). METHODS: Consecutive patients (55 with diffuse and 51 with limited SSc) without signs and symptoms of heart failure or a previous history of arterial hypertension underwent echocardiography and lung function tests. Aortic stiffness was determined non-invasively by aortic distensibility and aortic strain measurements in all patients and in 50 healthy subjects, matched for age and gender. RESULTS: Aortic distensibility in patients with either diffuse (2.03 +/- 0.26 x 10(-6) cm(2) dyn(-1)) or limited SSc (2.12 +/- 0.33) was similarly decreased compared with controls (2.49 +/- 0.36, P<0.001). Moreover, aortic strain was significantly reduced in both patient groups compared with controls, confirming that aortic stiffness is increased in SSc independently of the extent of skin involvement. Left ventricular performance was similar between patients and controls, while left ventricular mass and tricuspid systolic gradient were significantly increased in both SSc groups, the latter being associated with aortic stiffness in multivariate analysis. No association with serum levels of C-reactive protein or lung function abnormalities indicative of pulmonary fibrosis were found. CONCLUSIONS: Stiffness of the aorta is increased in patients with established SSc regardless of the extent of the inflammatory fibrotic process in the skin and lungs, suggesting that additional pathogenetic mechanisms contribute to the compromise of large arteries.

Aorta↗

Longitudinal development of skin involvement and reliability of high frequency ultrasound in systemic sclerosis.

BACKGROUND: Measurement of skin involvement is essential for diagnosis and prognosis in systemic sclerosis. Assessment by palpation skin score is the current method. OBJECTIVE: To explore high frequency ultrasound as an objective method to improve skin characterisation by combining measurements of skin thickness and echogenicity. METHODS: Skin thickness and echogenicity were measured at the proximal phalanx of the second digit, the back of the hand, the forearm, and the lower leg and, in order to separate limited (lSSc) from diffuse SSc (dSSc), at the chest in 16 patients with early disease and in 16 controls. Measurements were repeated in each patient three or four times with an interval of 1-2 years. Ultrasound measurements of skin thickness were compared with the palpation skin score. RESULTS: Compared with controls, the skin was thickened on the phalanx, hand, forearm, and chest of patients with dSSc, but not patients with lSSc, at the 1 year examination. In dSSc the degree of thickening tended to diminish with time, and at 4 years, thickness was significantly decreased on the forearm and chest compared with the 1 year measurements. Low reflectancy was most pronounced at the 1 year evaluation on the forearm, hand, and phalanx in dSSc, and on the phalanx in lSSc. CONCLUSION: Separate measurements of skin thickness and echogenicity by high frequency ultrasound add a new dimension to the assessment of skin involvement in SSc, and this seems to be an objective non-invasive tool for use in the study of disease development and in clinical trials.

Adult↗

Analysis of the 5' flanking region of the interleukin 10 gene in patients with systemic sclerosis.

OBJECTIVES: Fibrosis, a feature of systemic sclerosis (SSc), is more severe in the diffuse compared with the limited disease variant. Interleukin 10 (IL-10) is an anti-inflammatory cytokine which reduces type 1 collagen mRNA levels in human fibroblasts. The 5' flanking region of the IL-10 gene is highly polymorphic, with three single base pair substitutions at position -1082(G/A), -819(C/T) and -592(C/A), which results in differential IL-10 production. The GCC/GCC genotype is associated with high IL-10 production while the ATA/ATA genotype with low production. We postulated that there would be a difference in IL-10 polymorphisms in patients with limited (lSSc) and diffuse (dSSc) disease. METHODS: Patients with limited (lSSc, n = 89) or diffuse (dSSc, n = 51) disease plus controls (n = 94) were recruited. DNA was isolated from peripheral blood and polymorphisms analysed using amplification refractory mutation system (ARMS) polymerase chain reaction (PCR). RESULTS: dSSc patients were less likely to carry the genotype indicative of high IL-10 production when compared with controls (controls vs dSSc; 29 vs 4%, chi2 = 15.7, 5 df, P = 0.005) and lSSc patients (lSSc vs dSSc; 21 vs 4%, chi2 = 17.5, 5 df, P = 0.002). There was no difference between control and lSSc patients. While there was no difference between controls and lSSc haplotypes, the GCC haplotype distribution did differ significantly between controls and dSSc patients (controls vs dSSc; 54 vs 36%, chi2 = 11.2, 2 df, P = 0.001). A significant difference was also observed between lSSc and dSSc haplotype distribution (lSSc vs dSSc; 48 vs 36%, chi2 = 13.5, 2 df, P < 0.001). CONCLUSION: We demonstrate that IL-10 genotypes associated with high IL-10 production are under-represented in dSSc. This may have implications in the disease pathology.

DNA↗

Circulating levels of active transforming growth factor beta1 are reduced in diffuse cutaneous systemic sclerosis and correlate inversely with the modified Rodnan skin score.

OBJECTIVES: To determine the relationship between clinical features and circulating levels of active transforming growth factor (TGF) beta1 in the major subsets of systemic sclerosis (SSc). METHODS: In a cross-sectional study cases of diffuse cutaneous SSc (dose) (n = 27) or limited cutaneous SSc (dose) (n = 20) were compared with healthy controls (n = 22). Active and total TGFbeta1 was measured in serum and plasma by a high-sensitivity enzyme-linked immunosorbent assay. RESULTS: There were no significant differences between levels of total serum TGFbeta1. However, cases of dcSSc had lower levels of active TGFbeta1 than cases of lcSSc or controls. In addition, more cases of dcSSc (18/27; 66%, P < 0.025) had no detectable active TGFbeta1 than controls (7/22, 32%) or lcSSc (7/20, 35%). In dcSSc, serum active TGFbeta1 levels correlated negatively with skin score and positively with disease duration. CONCLUSIONS: Contrary to expectation, levels of active TGFbeta1 are reduced in dcSSc and this correlates with two variables known to associate with disease activity, shorter duration and more extensive skin sclerosis. This suggests that active TGFbeta1 may be sequestered in active involved SSc skin and that serum levels are reduced despite strong evidence implicating TGFbeta isoforms in the pathogenesis of fibrosis. Our findings may have implications for systemic TGFbeta-trapping therapies in this disease.

Adult↗

Association of TAP1 and TAP2 gene polymorphisms with systemic sclerosis in Korean patients.

We sought to determine whether transporter associated with antigen processing (TAP) gene polymorphism is associated with susceptibility to systemic sclerosis (SSc). TAP1 and TAP2 gene polymorphisms were analyzed in 61 Korean patients with SSc and 100 ethnically matched healthy Koreans by polymerase chain reaction-restriction fragment length polymorphism. Human leukocyte antigen (HLA)-DRB1 genotyping data of the patients from our previous study was used for the assessment of independent role of TAP genes to SSc susceptibility. Patients were stratified according to anti-topoisomerase I (anti-topo I) antibody status and clinical subsets of diffuse and limited cutaneous SSc (dcSSc and lcSSc). TAP1 and TAP2 gene polymorphisms were associated with different subsets of SSc: TAP1*A/A genotype with anti-topo I-positive dcSSc (p = 0.01, p corrected = 0.04), TAP2*A1/C genotype with anti-topo I-positive lcSSc (p < 0.05), TAP2*Bky2 and *C alleles with anti-topo I-negative dcSSc (both p < 0.05), and TAP2*B/E genotype with anti-topo I-negative lcSSc (p = 0.004). Although TAP gene associations were generally weak, some associations (TAP2*A1/C, TAP2*C, and TAP2*B/E) with different subsets of SSc were independent of HLA-DR associations, revealing even stronger associations (TAP2*A1/C and TAP2*C) among individuals not possessing the risk HLA-DR alleles. These results suggest the possible role of TAP gene polymorphisms in the genetic susceptibility to SSc.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Serum levels of a Th1 chemoattractant IP-10 and Th2 chemoattractants, TARC and MDC, are elevated in patients with systemic sclerosis.

BACKGROUND: Although abnormalities of various chemokines are detected in systemic sclerosis (SSc), there are few findings concerning Th1 or Th2 chemoattractants. OBJECTIVE: To determine whether serum levels of chemokines preferentially chemotactic for Th1 cells (IP-10 and MIG) and predominantly chemotactic for Th2 cells (TARC and MDC) are elevated and whether they correlate with clinical features in patients with SSc. METHODS: Serum samples from patients with diffuse cutaneous SSc (dSSc; n = 34), limited cutaneous SSc (lSSc; n = 30), dermatomyositis (DM; n = 15), systemic lupus erythematosus (SLE; n = 22), and normal controls (n = 30) were examined by sandwich ELISA. RESULTS: Serum TARC levels were significantly elevated in dSSc patients (P < 0.0002) and lSSc patients (P < 0.0001) compared with normal controls. Similarly, serum MDC levels were significantly increased in patients with dSSc (P < 0.02) or lSSc (P < 0.05) relative to normal controls. In addition, serum IP-10 was detected significantly more frequently in patients with dSSc (44%), lSSc (30%), or DM (53%) than normal controls (0%) and patients with SLE (0%). Furthermore, elevated TARC levels correlated with the presence of pitting scars and anti-topoisomerase I antibody, increased titers of anti-topoisomerase I and antinuclear antibody, and decreased glomerular filtration rate. Increased MDC levels were associated with pitting scars and younger ages at onset. CONCLUSION: These results suggest that both Th2 chemoattractants, TARC and MDC, and a Th1 chemoattractant IP-10 play a role in the development of SSc.

Adolescent↗

Prevalence of antiphospholipid antibodies in systemic sclerosis and association with primitive pulmonary arterial hypertension and endothelial injury.

OBJECTIVE: To investigate the prevalence and clinical significance of antiphospholipid antibodies in patients with systemic sclerosis (SSc). METHODS: Autoantibodies against cardiolipin (aCL) and beta2-glycoprotein 1 (beta2-GPI) were detected by enzyme-linked immunoabsorbent assays (ELISAs) in successively hospitalised SSc patients admitted during a 24-month period. These patients were compared to patients with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA). RESULTS: 108 SSc patients were included: 61 had limited cutaneous SSc, 47 had the diffuse sub-type, 16 had primitive pulmonary arterial hypertension (PAH) and 34 had digital ulcerations. The control groups consisted of 37 RA and 38 SLE patients. The prevalence of aCL positivity was lower in SSc patients vs SLE patients (14 vs 47%; p < 0.001), lower in RA patients vs SLE patients (19 vs 47%; p < 0.001), and not different in SSc vs RA patients (14 vs 19%; NS). The mean aCL titer was also lower in SSc vs SLE patients (8+/-10 vs 15+/-20; p < 0.001). In SSc patients, positivity for aCL was associated with PAH (p = 0.009) and the aCL titer correlated with that of the von Willebrand antigen factor (r= 0.23; p = 0.045). The prevalence of anti beta2-GPI positive patients (IgG and/or IgM) was 5% in the SSc group, 18% in the SLE group and 5% in the RA group (SLE vs SSc and SLE vs RA; p = 0.005). CONCLUSION: We found that the prevalence of antiphospholipid antibodies in SSc patients was low. However, aCL antibodies were associated with PAH and endothelial injury.

Adult↗

Distinct Effects of Complement C4A and C4B Copy Numbers in Systemic Sclerosis Serological and Clinical Subtypes.

OBJECTIVE: Complement component 4 (C4), encoded by C4A and C4B within the major histocompatibility complex (MHC) on chromosome 6, regulates the immune response and clears immune complexes. The variable copy number (CN) of C4 genes and retroviral human endogenous retrovirus K (HERV-K) element influence its function. Given the relationship of C4 CN with systemic sclerosis (SSc) risk, we assessed associations with SSc clinical and serologic subtypes. METHODS: We compared imputed C4 CNs across SSc subgroups (4,049 anticentromere positive [ACA+]; 2,200 anti-topoisomerase I [ATA+]; 577 anti-RNA polymerase [ARA+]; 1,078 triple-negative [TN] patients; 6,295 limited cutaneous SSc [lcSSc]; and 2,946 diffuse cutaneous SSc [dcSSc]) and 17,991 controls. We evaluated associations with SSc subtypes, identifying C4-independent HLA alleles. RESULTS: Lower C4 CN and higher HERV-K CN were associated with increased risk in all SSc subgroups. ATA+ patients showed the strongest association, particularly with C4A (odds ratio = 1.88), and differences in C4A CN association were more pronounced between autoantibody subgroups (ATA+ vs ACA+, P = 4 &#xd7; 10-11) than between clinical subgroups (dcSSc vs lcSSc, P = 1 &#xd7; 10-4). In ACA+ patients, only low C4B CN showed a significant association to SSc risk (P = 1.23 &#xd7; 10-5). We also observed sex-biased associations: dcSSc, ATA+, and ARA+ male patients showed stronger effects for C4A and ACA+ and lcSSc female patients for C4B. Finally, our results suggest that the HLA alleles associated with SSc subgroups are independent of C4 CN. CONCLUSION: This study highlights distinct genetic contributions of C4A and C4B in SSc subtypes susceptibility. Our findings suggest that lower C4 CNs, particularly C4A, increase the risk of the severe dcSSc subtype, potentially through a mechanism involving immune complex clearance.

Humans↗