Skin sclerosis is only of limited value to identify SSc patients with severe manifestations--an analysis of a distinct patient subgroup of the German Systemic Sclerosis Network (DNSS) Register

Therapeutic effects of thalidomide on patients with systemic sclerosis-associated interstitial lung disease

Objective

To evaluate the clinical efficacy of thalidomide in patients with systemic sclerosis-associated interstitial lung disease.

Methods

Ninety-six systemic sclerosis-associated interstitial lung disease patients who received basic glucocorticoid treatment and admitted between 2016 and 2020 were included in this study, including 48 cases in the thalidomide group (combination of thalidomide and cyclophosphamide) and 48 cases in control group (cyclophosphamide monotherapy). Evaluation items included clinical symptoms, modified Rodnan skin score, pulmonary function test, chest high-resolution computed tomography scores, and adverse effects between two groups after 24 weeks of treatment.

Results

Remarkable improvements in several aspects were found in the thalidomide group, including modified Rodnan skin score, expiratory dyspnea score, cough visual analog scale score, total ground-glass opacity score, and total interstitial lung disease score. Compared to the control group, improvements in the thalidomide group were found, such as significantly decreased cough visual analog scale score and expectoration; increased number of platelets; improved pulmonary fibrosis (p = 0.056), and reduced carbon monoxide diffusing capacity (p = 0.053). There were no statistically significant differences in the expiratory dyspnea score and predicted forced vital capacity between the two groups. Patients who experienced at least one adverse event in the control group and thalidomide group were 33.3% and 64.6% (p = 0.002); while those with serious adverse events were 8.3% versus 12.5% (p = 0.504). Venous thrombosis was found in one case in the thalidomide group.

Conclusion

Thalidomide combined with cyclophosphamide can improve the symptoms of cough and expectoration in patients with systemic sclerosis-associated interstitial lung disease, and may slightly delay the progression of pulmonary fibrosis, but with the possibility of an increased risk of adverse events.

Systematic Analysis of the Literature in Search of Defining Systemic Sclerosis Subsets

OBJECTIVE

Systemic sclerosis (SSc) is a multisystem disease with heterogeneity in presentation and prognosis.An international collaboration to develop new SSc subset criteria is underway. Our objectives were to identify systems of SSc subset classification and synthesize novel concepts to inform development of new criteria.

METHODS

Medline, Cochrane MEDLINE, the Cumulative Index to Nursing and Allied Health Literature, EMBASE, and Web of Science were searched from their inceptions to December 2019 for studies related to SSc subclassification, limited to humans and without language or sample size restrictions.

RESULTS

Of 5686 citations, 102 studies reported original data on SSc subsets. Subset classification systems relied on extent of skin involvement and/or SSc-specific autoantibodies (n = 61), nailfold capillary patterns (n = 29), and molecular, genomic, and cellular patterns (n = 12). While some systems of subset classification confer prognostic value for clinical phenotype, severity, and mortality, only subsetting by gene expression signatures in tissue samples has been associated with response to therapy.

CONCLUSION

Subsetting on extent of skin involvement remains important. Novel disease attributes including SSc-specific autoantibodies, nailfold capillary patterns, and tissue gene expression signatures have been proposed as innovative means of SSc subsetting.

Association of soluble urokinase plasminogen activator receptor levels with fibrotic and vascular manifestations in systemic sclerosis

OBJECTIVE

We assessed the association of suPAR (soluble urokinase plasminogen activator receptor) plasma levels with fibrotic and vascular manifestations in patients with systemic sclerosis (SSc).

METHODS

suPAR plasma levels were measured in 121 consecutive patients with SSc and correlated to pulmonary and vascular features of SSc, including interstitial lung disease as characterized by percentage of predicted CO diffusing capacity (DLco) and forced vital capacity (FVC), pulmonary fibrosis by computed tomography, and pulmonary arterial hypertension, telangiectasias, and digital ulcers.

RESULTS

Overall, 121 SSc patients (84% females; mean age, 57 ± 12 [range: 22-79] years) were enrolled; 35% had diffuse cutaneous SSc. suPAR plasma levels ranged from 1.3-10.2 [median: 2.9 (p25-p75: 2.3-3.9)] ng/mL. Log(suPAR) levels correlated with DLco (r = -0.41, p <0.0001) and FVC (r = -0.26, p = 0.004), also when adjusted for age, sex, and pulmonary hypertension. A suPAR cut-off level of >2.5 ng/mL showed a sensitivity of 91% for identifying patients with either DLco <50% or FVC < 60% of the predicted values. Similarly, 19 (90%) had a suPAR >2.5 ng/mL among those diagnosed with pulmonary fibrosis vs. 59 (60%) among those who did not (p = 0.008). suPAR values were not associated with vascular manifestations.

CONCLUSION

suPAR levels strongly correlated with pulmonary involvement in SSc. Future studies should test if suPAR estimation can be used for surveillance of severe pulmonary involvement in SSc.

Skin improvement is a surrogate for favourable changes in other organ systems in early diffuse cutaneous systemic sclerosis

OBJECTIVES

Skin improvement in diffuse cutaneous SSc (dcSSc), measured with modified Rodnan skin score (mRSS), is frequently used as a primary outcome in clinical trials, but it is uncertain whether mRSS changes reflect changes in other organ systems. This aim of this study was to explore if skin changes in early dcSSc over 1 and 2 years are associated with changes in severity of other organ involvement.

METHODS

Canadian Scleroderma Research Group database patients with dcSSc, disease duration of ≤5 years, no evidence of initial end-stage organ damage and/or significant comorbidity who had 1 year (n = 154) and 2 years (n = 128) of follow-up data were included. mRSS changes of 25% and/or ≥5 points were considered significant. Organ involvement was assessed by Medsger Disease Severity Score and Canadian Scleroderma Research Group definitions using bivariate, chi-square, ANOVA, adjusted regression and longitudinal mixed effect model analyses.

RESULTS

Improvement in mRSS was found in 41% of patients at 1 year and in 50% at 2 years. Improved patients showed less forced vital capacity decline (P = 0.012) and less frequent new cardiac involvement (P = 0.02) over 1 year, as well as better lung (by both Disease Severity Score, P = 0.006, and Δforced vital capacity%, P = 0.026), peripheral vascular (P = 0.006) and joint/tendon (P = 0.002) involvement over 2 years. mRSS worsening was consistently linked to less favourable lung outcomes at both 1- and 2-year follow-up visits, and more severe gastrointestinal disease at 2 years.

CONCLUSION

Changes in lung function in early dcSSc closely parallel skin changes. mRSS improvement reflects better prognosis for visceral disease and may be a reliable outcome measure in clinical trials.

[Systemic sclerosis]

Systemic sclerosis (SSc) is a rare fibrosing rheumatic multi-systemic disease involving many medical specialties. The mortality of SSc is determined by lung fibrosis, pulmonary arterial hypertension and cardiac involvement. With early and intensive treatment, the disease can be stabilized and symptoms relieved. This review summarizes insights into pathophysiology, disease classification, clinical manifestations and successful therapies, as well as recent studies on new immunosuppressant, biological and vasoactive therapies.

Subclinical dermal involvement is detectable by high frequency ultrasound even in patients with limited cutaneous systemic sclerosis

Background

The aim of the study was to detect by skin high-frequency ultrasound (US) possible subclinical skin involvement in patients affected by limited cutaneous systemic sclerosis (lcSSc), in those skin areas apparently not affected by the disease on the basis of a normal modified Rodnan skin score (mRSS). Differences in dermal thickness (DT) in comparison with healthy subjects were investigated.

Methods

Fifty patients with lcSSc (age 62 ± 13 years (mean ± SD), disease duration 5 ± 5 years) and 50 sex-matched and age-matched healthy subjects (age 62 ± 11 years) were enrolled. DT was evaluated by both mRSS and US at the usual 17 skin areas (zygoma, fingers, dorsum of the hands, forearms, upper arms, chest, abdomen, thighs, lower legs and feet). Non-parametric tests were used for the statistical analysis.

Results

Subclinical dermal involvement was detected by US even in the skin areas in patients with lcSSc, who had a normal local mRSS. In addition, statistically significantly higher mean DT was found in almost all skin areas, when compared to healthy subjects (p < 0.0001 for all areas). In particular, DT was significantly greater in patients with lcSSc than in healthy subjects in four out of six skin areas with a normal mRSS (score = 0) (upper arm, chest and abdomen), despite the clinical classification of lcSSc.

Conclusions

This study strongly suggests that subclinical dermal involvement may be detectable by US even in skin areas with a normal mRSS in patients classified as having lcSSc. This should be taken into account during SSc subset classification in clinical studies/trials.

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.

Cross-sectional study of soluble selectins, fractions of circulating microparticles and their relationship to lung and skin involvement in systemic sclerosis

Background

Endothelial damage and activation may play central roles in the pathogenesis of systemic sclerosis (SSc) and are reflected by microparticles (MPs) and soluble selectins. The objective of this study was to determine if these potential biomarkers are associated with specific organ involvements or cutaneous subgroups of SSc patients.

Method

MPs in platelet-poor plasma from 121 patients with SSc, 79 and 42 with limited and diffuse cutaneous disease, respectively, were characterized by flow cytometry for their capacity to bind annexin V in combination with surface markers of either platelets (PMPs), leukocytes (LMPs) or endothelial cells (EMPs). Soluble E- and P-selectin levels were determined in plasma. By correlation analyses, this was held against involvement of skin, lung function, lung fibrosis, pulmonary artery hypertension, and serology.

Results

None of the markers were associated with cutaneous subgroups of SSc. Concentrations of annexin V non-binding EMPs and annexin V non-binding LMPs were negatively correlated to pulmonary diffusing capacity (DL_CO) (r = -0.28; p = 0.003; r = -0.26; p = 0.005) and forced vital capacity (FVC) (r = -0.24; p = 0.009; r = -0.29; p = 0.002), driven by patients with limited and diffuse cutaneous disease, respectively. Soluble E-selectin levels correlated negatively to DL_CO (r = -0.21, p = 0.03) and FVC (r = -0.25; p = 0.007); and soluble P-selectin correlated negatively to DL_CO (r = -0.23, p = 0.01).

Conclusion

Negative correlations between annexin V non-binding EMP and LMP concentrations with lung function parameters (DL_CO and FVC) differed between limited and diffuse cutaneous subsets of SSc, indicative of various pathogeneses of lung involvement in SSc, possibly with a differential role of MPs.

Development of a modified hand mobility in scleroderma (HAMIS) test and its potential as an outcome measure in systemic sclerosis

OBJECTIVE

To modify the hand mobility in scleroderma (HAMIS) test by reducing the number of items and amount of equipment needed, and to evaluate the construct validity of this modified HAMIS (mHAMIS).

METHODS

Our retrospective study is based on 266 patients previously examined using the original HAMIS test. Data were divided into 3 groups depending on disease duration after onset: (1) 0-3 years, (2) 3.1-5 years, and (3) 5.1-9 years. Disease variables included were skin involvement using the disease subset and the modified Rodnan skin score (mRSS), and digital lesions. Cronbach's alpha coefficient was calculated separately for limited (lcSSc) and diffuse systemic sclerosis (dcSSc) for the right and left hand, and for the groups with different disease duration. The construct validity of the mHAMIS was assessed by searching for a correlation with hand skin score.

RESULTS

An mHAMIS test consisting of finger flexion, finger extension, finger abduction, and dorsal extension was developed. The internal consistency of this test was 0.78, 0.83, and 0.73 in the 3 groups with different disease duration. In the whole study group, mHAMIS showed a significant correlation with mRSS and hand skin score (rs=0.39 and 0.43, respectively), and was able to discriminate between lcSSc and dcSSc (p=0.001), and between patients with and without ulcers (p=0.015).

CONCLUSION

The mHAMIS involves 4 easily measurable items and has the potential to be a relevant clinical measure of outcome in the evaluation of fibrotic skin involvement in SSc.

The 15% rule in scleroderma: the frequency of severe organ complications in systemic sclerosis. A systematic review

OBJECTIVE

The prevalence of organ complications in scleroderma (systemic sclerosis; SSc) varies by definition used. This study was done to determine the frequency of several features of SSc.

METHODS

A search of Medline-Ovid/Embase, PubMed, and Scopus databases from 1980 to November 30, 2011, was conducted to identify relevant articles with at least 50 patients with SSc extracting prevalence of each organ complication. Study quality was assessed using the STROBE (Strengthening The Reporting of OBservational studies in Epidemiology) checklist. Pooled prevalence was calculated using the random effects method. Heterogeneity was quantified using I(2).

RESULTS

A total of 5916 articles were identified (913 from Medline-Ovid/Embase, 1009 from PubMed, and 3994 from Scopus); 5665 were excluded, leaving 251 articles for full-text review, with 69 included. Where available, frequencies were also included from the Canadian Scleroderma Research Group. Many severe complications in SSc occur about 15% of the time, including cardiac involvement (15%, 95% CI 6-24), diastolic dysfunction (16%, 95% CI 14-17), estimated pulmonary artery pressure > 40 mm Hg (18%, 95% CI 14-21), pulmonary arterial hypertension by right heart catheterization (15%, 95% CI 12-17), forced vital capacity (FVC) < 70% predicted (15%, 95% CI 12-17), FVC < 80% predicted (17%, 95% CI 12-21), myositis (13%, 95% CI 10-17), inflammatory arthritis (12%, 95% CI 9-16), Sjögren overlap (13%, 95% CI 10-16), and digital ulcers (DU; 15%, 95% CI 10-20); and 15% of DU have complications (amputations 12%, 95% CI 8-16, and hospitalizations 13%, 95% CI 6-21). Scleroderma renal crisis is uncommon but occurs in almost 15% (12%, 95% CI 5-19) of cases of disseminated cutaneous SSc. There is no 15% rule within skin and gastrointestinal tract for SSc.

CONCLUSION

The "15%" rule for frequency of significant organ involvement in SSc is helpful.

The degree of skin involvement identifies distinct lung disease outcomes and survival in systemic sclerosis

OBJECTIVE

To determine whether the pattern of skin involvement can predict clinical features, risk of restrictive lung disease (RLD) and survival in a large scleroderma (SSc) cohort.

METHODS

Demographic and clinical data collected over 30 years from 2205 patients with SSc were retrospectively analysed after subdividing subjects into four subtypes based on pattern of skin fibrosis: type 0 (no skin involvement), type 1 (limited to metacarpophalangeal joints), type 2 (distal to elbows/knees) and type 3 (proximal to elbows/knees). Clinical features associated with skin subsets were identified by regression analyses. Kaplan-Meier and Cox proportional hazards models were used to compare time to RLD and survival across subtypes.

RESULTS

The presence and severity of RLD were positively associated with skin subtype (p<0.001). RLD prevalence incrementally ranged from 51.9% in type 0 to 76.7% in type 3 (p<0.001). Type 2 SSc exhibited a distinct phenotype with intermediate risk for RLD relative to type 1 (higher, p<0.001) and type 3 (lower, p<0.001) and a unique autoantibody profile, with a prevalence of anticentromere antibodies lower than type 1 (28.9% vs 44.1%, p=0.001) and of anti-topoisomerase I antibodies similar to type 3 (32.8% vs 28.7%, p=0.38). These autoantibodies were also found to be significant negative (OR=0.33, p<0.001) and positive (OR=1.6, p=0.01) predictors of RLD risk, respectively. Mortality was also intermediate in type 2 patients relative to type 3 (p=0.0003) and type 1 (p=0.066).

CONCLUSIONS

These data suggest that the current classification subdividing SSc into limited and diffuse cutaneous subtypes misclassifies an intermediate group of patients exhibiting unique autoantibody profile, disease course and clinical outcomes.

[The German network for systemic sclerosis (DNSS): current data on diagnostics and therapy]

An essential prerequisite for progress in understanding the pathophysiology and the clinical treatment of rare diseases is the national cooperation of specialized centers. The German network for systemic sclerosis (DNSS) is such an interdisciplinary union of hospitals and research centers with a special interest in systemic sclerosis (SSc). A core activity is the patient register of the DNSS which includes over 3,100 patients. It is one of largest national registers of SSc patients worldwide and comprises prospective data on diagnostics as well as primarily therapy of the patients. The register has now proven to be an extremely successful basis for clinical research and basic studies within the framework of international cooperation. The most important results of the cooperation and the register will be presented in this article.

Magnetic resonance imaging findings in patients with systemic scleroderma and musculoskeletal symptoms

OBJECTIVE

To explore the role of whole-body magnetic resonance imaging (MRI) in detecting musculoskeletal involvement in patients with systemic scleroderma and musculoskeletal symptoms.

METHODS

Eighteen consecutive patients (8 men, 10 women) with systemic scleroderma (median age 46 years) presenting with musculoskeletal complaints underwent whole-body MRI at 1.5 T. Images were evaluated for abnormal signal intensity and/or thickening of subcutaneous fatty tissue septa, muscular fasciae, intramuscular perifascial septa, muscle signal intensity and articular or tendon sheath synovial abnormalities on STIR and post-gadolinium scans. Additionally, C-reactive protein, creatinine kinase and the modified Rodnan skin score were determined.

RESULTS

MRI indicated evidence of fasciitis, articular synovial inflammation, and subcutaneous thickening in 16 (89 %) patients. MRI findings were compatible with myopathy or myositis in 14 (78 %) patients, tenosynovitis in 11 (61 %) patients and enthesitis in 10 (56 %) patients. Typically, these manifestations were distributed symmetrically and mostly generalised. We only found few correlations with modified Rodnan skin score, C-reactive protein and creatinine kinase.

CONCLUSION

In patients with systemic scleroderma experiencing musculoskeletal symptoms, whole-body MRI is able to detect involvement of muscles, fasciae, joints and entheses more confidently compared with clinical and laboratory parameters.

Capturing the heterogeneity in systemic sclerosis with genome-wide expression profiling

Heterogeneity in the clinical presentation and basic science findings of systemic sclerosis (SSc) has hindered the understanding of pathogenesis and development of effective treatments. Genome-wide profiling of SSc has measured this heterogeneity. Gene expression studies of diffuse SSc skin have shown reproducible, disease-specific gene expression signatures when compared with healthy controls and, surprisingly, disease-specific gene expression was found in both lesional and non-lesional skin. SSc-specific gene expression in peripheral blood cells and the lungs has also been demonstrated. Hypothesis-driven approaches that assess the contribution of individual pathways provide insight into the etiology of gene expression subsets.

Predicting treatment outcomes and responder subsets in scleroderma-related interstitial lung disease

OBJECTIVE

To identify baseline characteristics of patients with scleroderma-related interstitial lung disease (SSc-ILD) that could serve as predictors of the most favorable response to 12-month treatment with oral cyclophosphamide (CYC).

METHODS

Regression analyses were retrospectively applied to the Scleroderma Lung Study data in order to identify baseline characteristics that correlated with the absolute change in forced vital capacity (FVC) (% predicted values) and the placebo-adjusted change in % predicted FVC over time (the CYC treatment effect).

RESULTS

Completion of the CYC arm of the Scleroderma Lung Study was associated with a placebo-adjusted improvement in the % predicted FVC of 2.11% at 12 months, which increased to 4.16% when patients were followed up for another 6 months (P=0.014). Multivariate regression analyses identified the maximal severity of reticular infiltrates (assessed as maximum fibrosis scores) on high-resolution computed tomography (HRCT) at baseline, the modified Rodnan skin thickness score (MRSS) at baseline, and the Mahler baseline dyspnea index as independent correlates of treatment response. When patients were stratified on the basis of whether 50% or more of any lung zone was involved by reticular infiltrates on HRCT and/or whether patients exhibited an MRSS of at least 23, a subgroup of patients emerged in whom there was an average CYC treatment effect of 9.81% at 18 months (P<0.001). Conversely, there was no treatment effect (a -0.58% difference) in patients with less severe HRCT findings and a lower MRSS at baseline.

CONCLUSION

A retrospective analysis of the Scleroderma Lung Study data identified the severity of reticular infiltrates on baseline HRCT and the baseline MRSS as patient features that might be predictive of responsiveness to CYC therapy.

Course of dermal ulcers and musculoskeletal involvement in systemic sclerosis patients in the scleroderma lung study

OBJECTIVE

To evaluate changes in vascular and musculoskeletal involvement in subjects in the Scleroderma Lung Study, a multicenter, double-blind, randomized, controlled trial comparing placebo treatment with oral cyclophosphamide (CYC) for 1 year in systemic sclerosis patients with interstitial lung disease. Subjects were then followed off the study agent for an additional 12 months.

METHODS

The following parameters were noted at baseline and every 6 months for each patient: digital tip ulcers, other dermal ulcers, joint swelling, joint tenderness, large joint contractures, muscle tenderness, muscle weakness, oral aperture, hand extension, and fist closure.

RESULTS

A total of 158 patients were enrolled from 13 centers in the US; 79 were randomized to the CYC group and 79 to the placebo group. There were no differences in dermal ulcer and musculoskeletal measures between the CYC and placebo groups at baseline and 12 and 24 months. Improvement in percent predicted forced vital capacity was associated with improvement in the Rodnan skin thickness score (P<0.05) at 12 and 24 months, and with increased mean oral aperture at 24 months (P=0.005).

CONCLUSION

These data document the frequency and course of these vascular and musculoskeletal features over time, therefore providing essential information for sample size calculations and magnitude of effect in future clinical trials. There was no treatment effect of CYC on the vascular and musculoskeletal features described.

Rheumatic manifestations of skin disease

PURPOSE OF REVIEW

There is an increasing interest in improving the understanding of pathophysiology, outcome measures, and therapies of rheumatic skin disease. Increasingly, studies are using the skin as a primary endpoint for evaluating therapies. This will review the current state of the art for the most common rheumatic skin diseases.

RECENT FINDINGS

A number of medications, including biologics such as tumor necrosis factor alpha and interferon, have been associated with onset of cutaneous lupus. The cutaneous lupus erythematosus area and severity index has been further validated and utilized in a number of studies. Smoking continues to be associated both with presence and refractoriness of cutaneous lupus erythematosus to therapy. There are several tools now available for evaluating the skin disease of dermatomyositis, but there is a need for new effective therapies. Measurement of skin disease in scleroderma continues to be a challenge, and there is a need for more effective therapies. Several studies show efficacy of intravenous iloprost for severe Raynaud's and skin ulcers, and of bosentan for digital ulcers.

SUMMARY

The present review covers new outcome measures, treatments, and unusual manifestations of cutaneous lupus, dermatomyositis, scleroderma, and rheumatoid arthritis. There have been a number of new studies related to validation of disease activity measures, as well as their use in evaluation of new therapies for these conditions. Validated outcome measures are required to perform meaningful studies, and will facilitate organized epidemiologic, quality of life, and therapeutic studies.

Diagnostic value of anti-topoisomerase I antibodies in a large monocentric cohort

Introduction

In the present study, the detection of anti-topoisomerase I (anti-topo I) autoantibodies was evaluated for diagnosis and risk assessment of systemic sclerosis (SSc) patients in a well characterized large monocentric cohort.

Methods

Sera from patients with SSc (diffuse n = 96, limited n = 113), from patients with overlap syndromes (n = 51), from patients with other diseases associated with SSc (n = 20), as well as from disease controls (n = 487) were analysed for the presence of anti-topo I antibodies by line immunoblot assay and ELISA. Assessment of organ manifestations was performed as proposed by the European Scleroderma Trial and Research network.

Results

The applied test systems for the detection of anti-topo I antibodies revealed a diagnostic sensitivity for SSc of approximately 24% and a diagnostic specificity of at least 99.6%. The sensitivity to identify patients with diffuse SSc amounted to 60%. Patients with anti-topo I antibodies showed a higher burden of skin and lung fibrosis, contractures, electrocardiogram changes, as well as digital ulcers and had more active disease than antibody-negative patients. Signal strengths correlated only weakly with disease activity, with modified Rodnan skin score, with predicted forced vital capacity, and with predicted diffusion capacity levels (P = 0.01, ρ = 0.234, ρ = 0.413, ρ = -0.215, ρ = -0.219). High signal intensities were associated with an increased mortality in diffuse SSc patients (P = 0.003).

Conclusions

Diagnosis and risk assessment of SSc patients can be supported by the detection of anti-topo I antibodies. Signal intensities as obtained by line immunoblot assay or ELISA can be used as a surrogate marker for fibrosis, active disease and worse prognosis.