Unique clinical and autoantibody profile of a large Asian Indian cohort of scleroderma-do South Asians have a more aggressive disease?

Systemic sclerosis patients with negative antinuclear antibodies have distinctive clinical manifestations: a multicenter CRDC cohort in China

BACKGROUND

The presence of circulating antinuclear antibodies (ANAs) is a hallmark of immune dysregulation in patients with systemic sclerosis (SSc).

OBJECTIVE

A variety of ANAs are associated with unique sets of disease manifestations and are widely used in clinical practice in SSc. This study aimed to investigate the clinical features of SSc patients negative for ANAs in a Chinese Rheumatism Data Center (CRDC) multicenter cohort in China.

METHODS

Patients were prospectively recruited between April 2008 and June 2019 from 154 clinical centers nationwide, and all cases fulfilled the 2013 ACR/EULAR classification criteria for systemic sclerosis. Results for antinuclear antibodies were intensively collected. Demographic, clinical, and laboratory data were compared between ANA-positive SSc patients and those negative for ANAs.

RESULTS

Antinuclear antibodies were detected in 2129 of 2809 patients enrolled in the study; 4.2% of patients were negative. There were more males among ANA-negative SSc patients (29/60 vs. 294/1746, p < 0.001). The incidence of certain critical organ involvement, including gastroesophageal reflux (5.6% vs. 18.5%, p = 0.002), interstitial lung disease (65.2% vs. 77.9%, p = 0.015), and pulmonary arterial hypertension (11.5% vs. 29.0%, p = 0.006) was significantly lower in ANA-negative patients than in ANA-positive patients. The proportion of abnormal erythrocyte sedimentation rate (32.4% vs. 47.6%, p = 0.013) and IgG elevation (14.3% vs. 37.0%, p = 0.003), an indicator of disease activity, was significantly lower in ANA-negative patients than in ANA-positive patients.

CONCLUSION

Antinuclear antibodies are strongly associated with the clinical manifestations of systemic sclerosis, with ANA-negative SSc patients tending to exhibit relatively milder disease.

Exploratory clinical subgroup clustering in systemic sclerosis: Results from the Indian Progressive Systemic Sclerosis Registry

Objective

To conduct an exploratory cluster analysis of systemic sclerosis patients from the baseline data of the Indian systemic sclerosis registry.

Methods

Patients satisfying American College of Rheumatology-European League Against Rheumatism classification criteria for systemic sclerosis were included. The clusters formed using clinical and immunological parameters were compared.

Results

Of the 564 systemic sclerosis registry participants, 404 patients were included. We derived four clusters of which three were anti-topoisomerase I predominant and one was anti-centromere antibody 2 dominant. Cluster 1 (n-82 (20.3%)) had diffuse cutaneous systemic sclerosis patients with the most severe skin disease, anti-topoisomerase I positivity, males, younger age of onset and high prevalence of musculoskeletal, vasculopathic and gastrointestinal features. Cluster 2 (n-141 (34.9%)) was also diffuse cutaneous systemic sclerosis and anti-topoisomerase I predominant but with less severe skin phenotype than cluster 1 and a lesser prevalence of musculoskeletal, vasculopathic and gastrointestinal features. Cluster 3 (n-119 (29.5%)) had limited cutaneous systemic sclerosis patients with anti-topoisomerase I positivity along with other antibodies. The proximal muscle weakness was higher and digital pitting scars were lower, while other organ involvement was similar between clusters 2 and 3. Cluster 4 (n-62 (15.30%)) was the least severe group with limited cutaneous systemic sclerosis and anti-centromere antibody predominance. Age of onset was higher with low musculoskeletal disease and a higher presence of upper gastrointestinal features. The prevalence of interstitial lung disease was similar in the three anti-topoisomerase I predominant clusters.

Conclusion

With exploratory cluster analysis, we confirmed the possibility of subclassification of systemic sclerosis along a spectrum based on clinical and immunological characteristics. We also corroborated the presence of anti-topoisomerase I in limited cutaneous systemic sclerosis and the association of interstitial lung disease with anti-topoisomerase I.

Heterogeneity of determining disease severity, clinical course and outcomes in systemic sclerosis-associated interstitial lung disease: a systematic literature review

Objective The course of systemic sclerosis-associated interstitial lung disease (SSc-ILD) is highly variable and different from continuously progressive idiopathic pulmonary fibrosis (IPF). Most proposed definitions of progressive pulmonary fibrosis or SSc-ILD severity are based on the research data from patients with IPF and are not validated for patients with SSc-ILD. Our study aimed to gather the current evidence for severity, progression and outcomes of SSc-ILD.Methods A systematic literature review to search for definitions of severity, progression and outcomes recorded for SSc-ILD was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in Medline, Embase, Web of Science and Cochrane Library up to 1 August 2023.Results A total of 9054 papers were reviewed and 342 were finally included. The most frequent tools used for the definition of SSc-ILD progression and severity were combined changes of carbon monoxide diffusing capacity (DLCO) and forced vital capacity (FVC), isolated FVC or DLCO changes, high-resolution CT (HRCT) extension and composite algorithms including pulmonary function test, clinical signs and HRCT data. Mortality was the most frequently reported long-term event, both from all causes or ILD related.Conclusions The studies presenting definitions of SSc-ILD 'progression', 'severity' and 'outcome' show a large heterogeneity. These results emphasise the need for developing a standardised, consensus definition of severe SSc-ILD, to link a disease specific definition of progression as a surrogate outcome for clinical trials and clinical practice.PROSPERO registration number CRD42022379254.Cite Now.

Clinical and autoantibody profiles of systemic sclerosis patients: A cross-sectional study from North India

Objectives This cross-sectional study was designed to assess the clinical profile and frequency of associated autoantibodies in all consecutive patients classified as systemic sclerosis (SSc) at Medanta-the Medicity Hospital, Gurgaon, India. Methods Between August 2017 and July 2019, we identified a total of 119 consecutive patients meeting the American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) 2013 criteria for SSc and 106 patients consented to this study. Their clinical and serological data at the time of enrolment were analysed. Results Our cohort had a mean age at symptom onset of 40 ± 13 years with a median symptom duration of 6 years. We had 76 patients (71.7%) with interstitial lung disease (ILD), which was a higher proportion compared to European cohorts. 62 patients (58.5%) had diffuse cutaneous involvement which was significantly associated with anti-Scl70 antibodies (p < 0.001), digital ulcers (p = 0.039) and the presence of ILD (p = 0.004). 65 patients (61.3%) had anti-Scl70 and 15 patients (14.2%) had anti-centromere (anti-CENP) antibodies. Scl70 positivity was associated with the presence of ILD (p < 0.001) and digital ulcers (p = 0.01). Centromere antibodies had a negative association with ILD (p < 0.001), but was a risk factor for calcinosis (p < 0.001) and pulmonary arterial hypertension (PAH) (p = 0.01). The combination of diffuse cutaneous disease and Scl70 antibodies was the strongest predictor of ILD and digital ulcers (p = 0.015). sm/RMP, RNP68 and Ku antibodies correlated with musculoskeletal involvement (p < 0.01), while all seven of the patients with Pm/Scl antibodies had ILD. Renal involvement was noted in only two patients. Limitations A single-centre study may not capture the true prevalence of disease characteristics in the population. Referral bias for patients with diffuse cutaneous disease has been noted. Data on RNA-Polymerase antibodies have not been provided. Conclusion North Indian patients have some characteristic differences in disease phenotype as compared to their Caucasian counterparts with a larger proportion of patients presenting with ILD and Scl70 antibodies. Antibodies against Ku, RNP and Pm/Scl occur in a minority of patients, but may be associated with musculoskeletal features.

Incidence and prevalence of interstitial lung diseases worldwide: a systematic literature review

Interstitial lung disease (ILD) is a collective term representing a diverse group of pulmonary fibrotic and inflammatory conditions. Due to the diversity of ILD conditions, paucity of guidance and updates to diagnostic criteria over time, it has been challenging to precisely determine ILD incidence and prevalence. This systematic review provides a synthesis of published data at a global level and highlights gaps in the current knowledge base. Medline and Embase databases were searched systematically for studies reporting incidence and prevalence of various ILDs. Randomised controlled trials, case reports and conference abstracts were excluded. 80 studies were included, the most described subgroup was autoimmune-related ILD, and the most studied conditions were rheumatoid arthritis (RA)-associated ILD, systemic sclerosis associated (SSc) ILD and idiopathic pulmonary fibrosis (IPF). The prevalence of IPF was mostly established using healthcare datasets, whereas the prevalence of autoimmune ILD tended to be reported in smaller autoimmune cohorts. The prevalence of IPF ranged from 7 to 1650 per 100 000 persons. Prevalence of SSc ILD and RA ILD ranged from 26.1% to 88.1% and 0.6% to 63.7%, respectively. Significant heterogeneity was observed in the reported incidence of various ILD subtypes. This review demonstrates the challenges in establishing trends over time across regions and highlights a need to standardise ILD diagnostic criteria.PROSPERO registration number: CRD42020203035.

Prevalence of and factors independently associated with digital ischemic complications in patients with systemic sclerosis

Objective

To investigate the prevalence of and independent predictors for digital ischemic complications in patients with systemic sclerosis.

Method

Patients enrolled in the Siriraj Systemic Sclerosis Cohort registry during 2013-2019 were classified as having or not having digital ischemic complications at the baseline and 1-year timepoints.

Results

A total of 171 patients with systemic sclerosis were included. The prevalence of digital pulp loss, digital pitting scar, digital ulcer, and digital amputation at baseline and 1 year was 41.5%, 39.8%, 3.5%, 7.6% and 37.4%, 43.9%, 14.1%, 6.4%, respectively. Over half (58.5%) of overall systemic sclerosis had developed new digital ischemic complications during the 1-year follow-up. Those with digital ischemic complications at baseline were at high risk for developing new digital ischemic complications (odds ratio: 15.9). Diffuse cutaneous systemic sclerosis is associated with digital ischemic complications (odds ratio: 6.0), digital pitting scar (odds ratio: 4.9), and digital pulp loss (odds ratio: 6.4). Tendon friction rub is associated with digital pitting scar (odds ratio: 5.0). Salt-and-pepper skin appearance is associated with digital pulp loss (odds ratio: 3.0) and digital ulcer (odds ratio: 6.9). Disease duration > 3 years is associated with digital ulcer (odds ratio: 4.4). Male gender is associated with digital ulcer (odds ratio: 5.4).

Conclusion

Digital pulp loss, digital pitting scar, digital ulcer, and digital amputation were common manifestations of digital ischemic complications, and diffuse cutaneous systemic sclerosis was the strongest of the six independent predictors.

Systemic sclerosis in Asians: Are there racial differences?

Systemic sclerosis is a multisystemic autoimmune disease characterized by vasculopathy and fibrosis. Racial factors exert a significant influence on the epidemiology, clinical manifestations, antibody profile, mortality and genetic factors in systemic sclerosis. In this review, we examined Asian systemic sclerosis cohorts reported in Asia and multi-racial cohort studies to evaluate the disease characteristics and outcomes of systemic sclerosis in Asians. Asian patients have distinct genetic susceptibility to systemic sclerosis, younger age of systemic sclerosis onset, higher frequency of diffuse skin involvement, different autoantibody profiles such as higher frequency of anti-Scl70 and anti-U1-RNP antibodies, and more severe clinical phenotype. There was a suggestion of poorer survival among Asians that may be contributed by more severe disease, socioeconomic factors and differences in healthcare systems. Recognizing the influence of racial differences in systemic sclerosis disease course is important as it has implications for appropriate treatment, monitoring and prognostication.

Antinuclear antibody pattern and autoantibody profiling of systemic sclerosis patients in a tertiary referral center in North India

Antinuclear antibody (ANA) pattern and autoantibody (autoAb) profiling of 150 adult systemic sclerosis (SSc) patients concerning their clinical association and diagnostic significance were analyzed by indirect immunofluorescence (IIF), immunoblot, and fluorescence enzyme immunoassay. One hundred and forty-three (95.3%) patients had positive ANA: DNA topoisomerase I (topo I)-like pattern-84(56%); speckled pattern-44(29.3%);centromere pattern-7(4.6%); and nucleolar pattern-4(2.6%). Three distinct topo I-like immunofluorescence patterns were detected at 1:40 dilution. Topo I-like pattern (32/75-limited cutaneous systemic sclerosis (lcSSc) vs. 52/75-diffuse cutaneous systemic sclerosis (dcSSc); p < 0.001) was found to be associated with dcSSc subset and speckled pattern (lcSSc 28/75 vs. dcSSc 16/75; p < 0.03) with lcSSc subset. One hundred and thirty-eight (92%) patients were positive for SSc-associated autoAbs. The frequency distribution of autoAbs to topo I, centromere A (CENP A) and centromereB (CENP B), RNA polymerase III (RP11, RP155), fibrillarin (U3RNP), nucleolus organizer region (NOR)-90, Th/To, PM-Scl75, PM-Scl100, Ku, platelet-derived growth factor receptor (PDGFR) and Ro-52, were 87(58%), 9(6%), 8(5.3%), 6(4%), 9(6%), 0, 6(4%), 6(4%), 8(5.3%), 5(3.3%), 11(7.3%),0 and 46(30.6%), respectively. Topo I autoAb was strongly associated with dcSSc (35/75 lcSSc vs. 52/75 dcSSc; p < 0.004), Raynaud's (p < 0.003), interstitial lung disease (ILD) (p < 0.001) and pulmonary arterial hypertension (PAH) (p < 0.04). This study helps in defining SSc clinical subset, prognostic markers of disease severity, characterization of the topo I-like ANA pattern, and provides a definite association between the ANA patterns and corresponding autoAb.

Mycophenolate in scleroderma-associated interstitial lung disease: Real-world data from rheumatology and pulmonology clinics in South Asia

INTRODUCTION

There is a paucity of real-world data on mycophenolate mofetil/mycophenolate sodium in systemic sclerosis-related interstitial lung disease.

AIM

To study the efficacy of mycophenolate mofetil/ mycophenolate sodium in systemic sclerosis-related interstitial lung disease.

METHODS

In this single-centre study, clinical, laboratory and imaging details of consecutive patients with systemic sclerosis-related interstitial lung disease receiving mycophenolate mofetil/mycophenolate sodium from rheumatology and pulmonology clinics between January 2008 and March 2017 were retrospectively retrieved. The change in percentage of predicted normal forced vital capacity at last follow-up visit as compared with baseline was studied. In addition, high-resolution computed tomography scans at baseline and 2-year follow-up visit were scored as either stable/improved or worsened by experienced thoracic radiologists blinded to the clinical details of patients.

RESULTS

Altogether, 88 patients (85.2% females) with mean age (SD) of 33.8 years (± 11.3) and median (interquartile range) duration of disease since non-Raynaud's symptoms of 36 months (13.5-60) were studied. Diffuse systemic sclerosis comprised 85.2% of them. The mean baseline forced vital capacity was 61.2 ± 17.9% and median scores for ground glass opacities and fibrosis in high-resolution computed tomography were 0.5 (0-1.3) and 1 (0-1.3), respectively. At a median follow-up duration of 30 months (interquartile range = 16.5-49), the percentage of forced vital capacity improved by 1.8% (-3.82 to 9.07) as compared with baseline visit (p = 0.02). In the 2-year follow-up, the ground glass opacity and fibrosis scores in high-resolution computed tomography improved in 17.3% and 7.7% of patients and stabilized in 63.5% and 78.8% patients, respectively.

CONCLUSION

Mycophenolate mofetil/mycophenolate sodium was efficacious in improving /stabilizing forced vital capacity irrespective of the baseline high-resolution computed tomography lung scores in our patients with systemic sclerosis-related interstitial lung disease during the ⩾ 2-year follow-up period.

Natural Formulations: Novel Viewpoint for Scleroderma Adjunct Treatment

BACKGROUND

Scleroderma is a complex disease involving autoimmune, vascular, and connective tissues, with unknown etiology that can progress through any organ systems.

OBJECTIVE

Yet, no cure is available; the thorough treatment of scleroderma and current treatments are based on controlling inflammation. Nowadays, medicinal plants/natural-based formulations are emerging as important regulators of many diseases, including autoimmune diseases. Here, we provided an overview of scleroderma, also focused on recent studies on medicinal plants/natural-based formulations that are beneficial in scleroderma treatment/prevention.

METHODS

This study is the result of a search in PubMed, Scopus, and Cochrane Library with "scleroderma", "systemic sclerosis", "plant", "herb", and "phytochemical" keywords. Finally, 22 articles were selected from a total of 1513 results entered in this study.

RESULTS

Natural products can modulate the inflammatory and/or oxidative mediators, regulate the production or function of the immune cells, and control the collagen synthesis, thereby attenuating the experimental and clinical manifestation of the disease.

CONCLUSION

Natural compounds can be considered an adjunct treatment for scleroderma to improve the quality of life of patients suffering from this disease.

Increased Mortality in Asians With Systemic Sclerosis in Northern California

Objective

The objective of this study is to evaluate racial/ethnic differences in disease manifestations and survival in a US cohort of patients with systemic sclerosis (SSc), with a focus on Asian patients.

Methods

A retrospective cohort study was conducted among Kaiser Permanente Northern California adults with an incident SSc diagnosis by a rheumatologist from 2007 to 2016, confirmed by a chart review to fulfill 2013 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) classification criteria. Self‐reported race/ethnicity was categorized as non‐Hispanic white, Asian, Hispanic, and black. Disease manifestations and survival were compared, using white patients as the reference.

Results

A total of 609 patients with incident SSc were identified: 89% were women, and 81% had limited cutaneous SSc, with a mean age at diagnosis of 55.4 ± 14.8 years. The racial/ethnic distribution was 51% non‐Hispanic white (n = 310), 25% Hispanic (n = 154), 16% Asian (n = 96), and 8% black (n = 49). Compared with white patients, black patients had a greater prevalence of diffuse disease (14.5% vs. 44.9%; P < 0.001), and Asians had higher rates of anti‐U1‐RNP antibodies (32.1% vs. 11.9%; P = 0.005). Nine‐year overall survival rates following SSc diagnosis were lower in Asian (52.3%), black (52.2%), and Hispanic patients (68.2%) compared with white patients (75.8%). Pulmonary hypertension and infections were the leading causes of death in Asian patients. Asian race was associated with higher mortality on univariable (hazard ratio [HR] 1.83 [95% confidence interval (CI) 1.08‐2.99]; P = 0.020) and multivariable analyses (HR 1.80 [95% CI 0.99‐3.16]; P = 0.047) when adjusting for age, sex, body mass index, cutaneous subtype, smoking status, interstitial lung disease, pulmonary hypertension, renal crisis, and malabsorption syndrome.

Conclusion

Asian patients with SSc in this US cohort had increased mortality compared with white patients. These patients warrant close monitoring for disease progression.