Influence of ethnic background on clinical and serologic features in patients with systemic sclerosis and anti-DNA topoisomerase I antibody

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.

Efficacy and safety of tocilizumab in Japanese patients with systemic sclerosis and associated interstitial lung disease: A subgroup analysis of a global, randomised, controlled Phase 3 trial

OBJECTIVES

The aim of this article is to investigate the efficacy and safety of tocilizumab in Japanese patients with systemic sclerosis.

METHODS

Post hoc subgroup analysis of a global, randomised, controlled trial in patients treated with weekly tocilizumab 162 mg or placebo subcutaneously in a 48-week double-blind period (tocilizumab and placebo groups) followed by tocilizumab for 48 weeks in an open-label extension (continuous-tocilizumab and placebo-tocilizumab groups).

RESULTS

Among 20 patients, 12 were randomised to tocilizumab (all had interstitial lung disease) and eight were randomised to placebo (six had interstitial lung disease). The modified Rodnan skin score improved in both treatment groups. The mean change in percent-predicted forced vital capacity was 3.3% [95% confidence interval (CI), -2.5 to 9.0] for tocilizumab and -3.8% (95% CI, -9.9 to 2.2) for placebo in the double-blind period and 2.0% (95% CI, -0.7 to 4.6) for continuous-tocilizumab and -1.4% (95% CI, -6.7 to 4.0) for placebo-tocilizumab in the open-label extension. Rates of serious adverse events per 100 patient-years were 19.3 for tocilizumab and 26.8 for placebo in the double-blind period and 0.0 for continuous-tocilizumab and 13.6 for placebo-tocilizumab in the open-label period.

CONCLUSIONS

The efficacy and safety of tocilizumab in patients with systemic sclerosis were consistent between the Japanese subpopulation and the global trial population.

Pulmonary toxicity of immune checkpoint immunotherapy

Cancer remains a leading cause of mortality on a global scale. Lung cancer, specifically non-small cell lung cancer (NSCLC), is a prominent contributor to this burden. The management of NSCLC has advanced substantially in recent years, with immunotherapeutic agents, such as immune checkpoint inhibitors (ICIs), leading to improved patient outcomes. Although generally well tolerated, the administration of ICIs can result in unique side effects known as immune-related adverse events (irAEs). The occurrence of irAEs involving the lungs, specifically checkpoint inhibitor pneumonitis (CIP), can have a profound effect on both future therapy options and overall survival. Despite CIP being one of the more common serious irAEs, limited treatment options are currently available, in part due to a lack of understanding of the underlying mechanisms involved in its development. In this Review, we aim to provide an overview of the epidemiology and clinical characteristics of CIP, followed by an examination of the emerging literature on the pathobiology of this condition.

Damage Trajectories in Systemic Sclerosis Using Group-Based Trajectory Modeling

OBJECTIVE

Systemic sclerosis (SSc) is an autoimmune disease characterized by progressive organ damage, which can be measured using the Scleroderma Clinical Trials Consortium Damage Index (SCTC-DI). We aimed to identify whether distinct trajectories of damage accrual exist and to determine which variables are associated with different trajectory groups.

METHODS

Incident cases of SSc (<2 years) were identified in the Australian Scleroderma Interest Group and Canadian Scleroderma Research Group prospective registries. Group-based trajectory modeling was used to identify SCTC-DI trajectories over the cohort's first 5 annual visits. Baseline variables associated with trajectory membership in a univariate analysis were examined in multivariable models.

RESULTS

A total of 410 patients were included. Three trajectory groups were identified: low (54.6%), medium (36.2%), and high (10.3%) damage. Patients with faster damage accrual had higher baseline SCTC-DI scores. Older age (odds ratio [OR] 1.57 [95% confidence interval (95% CI) 1.18-2.10]), male sex (OR 2.55 [95% CI 1.10-5.88]), diffuse disease (OR 6.7 [95% CI 2.57-17.48]), tendon friction rubs (OR 5.4 [95% CI 1.86-15.66]), and elevated C-reactive protein level (OR 1.98 [95% CI 1.49-2.63]) increased the odds of being in the high-damage group versus the reference (low damage), whereas White ethnicity (OR 0.31 [95% CI 0.12-0.75]) and anticentromere antibodies (OR 0.24 [95% CI 0.07-0.77]) decreased the odds.

CONCLUSION

We identified 3 trajectories of damage accrual in a combined incident SSc cohort. Several characteristics increased the odds of belonging to worse trajectories. These findings may be helpful in recognizing patients in whom early aggressive treatment is necessary.

Formative research to promote lupus awareness and early screening at Historically Black College and University (HBCU) communities in South Carolina

BACKGROUND

Systemic lupus erythematosus or lupus is a severe chronic autoimmune disorder that disproportionately impacts young African Americans. Increasing lupus awareness in this high-risk group may be an effective approach to ultimately improving lupus outcomes. To begin to address this disparity, this report describes qualitative data to be utilized in the development of a campaign to enhance awareness of lupus on Historically Black Colleges and University (HBCU) campuses.

METHODS

Two focus groups (N = 14) were held with African American students in the network of HBCU's in South Carolina to examine perspectives of focus group participants on knowledge, awareness, and experiences with lupus.

RESULTS

Five key emergent themes included: (1) Lupus Knowledge and Awareness, (2) Barriers for Not Seeking Healthcare, (3) Fatalism for Disease Burden, (4) Lifestyle Debilitation, and (5) Elevation of Education and Advocacy for Lupus. Additionally, five key recommendations emerged to improve lupus awareness and support, including: (1) remaining positive, (2) developing a supportive network, (3) the importance of increasing advocacy efficacy, and (4) messaging strategies around lupus, and (5) providing education to foster knowledge around the clinical impacts of lupus.

CONCLUSION

Participants in our study stressed the necessity of lupus education and awareness among African American youth and expressed the desire for resources that would enable them to advocate for themselves and their families. Given the early age of onset for lupus, it is therefore vital to include African American youth in increasing education and awareness about lupus.

Systemic sclerosis in Native Americans of the American Southwest

OBJECTIVE

Many indigenous non-Caucasian populations, including Native Americans, have been reported to have higher rates, distinct clinical phenotypes, increased complications, and greater severity of systemic sclerosis (SSc). However, little is known of SSc specifically in Native Americans of the American Southwest. This study compared the clinical and serologic manifestations and outcomes of SSc in Native Americans and non-Native Americans (non-Natives) of this region.

METHODS

This cross-sectional retrospective study included 137 SSc patients (109 [80%] were non-Native and 28 [20%] were Native Americans) followed over a mean of 11.5 ± 7.6 years. Participants were repetitively evaluated with medical history, physical examination, echocardiography, chest imaging, and serologic testing. Disease characteristics and outcomes were statistically compared between Native Americans and non-Native patients.

RESULTS

The estimated prevalence of SSc in Native Americans was 40.0 cases/100 000 vs 17.1 cases/100 000 for non-Natives (odds ratio 2.34, 95% confidence interval [CI] 1.55-3.55, P < .001). The cohorts were similar in terms age, age of onset, limited vs diffuse cutaneous SSc, telangiectasias, gastroesophageal reflux disease, Raynaud phenomenon, serologies, interstitial lung disease, pulmonary arterial hypertension, scleroderma renal crisis, cancer prevalence, and overall mortality (all P > .05). However, for Native Americans, mortality specifically from fatal infections was 3.94-fold that of non-Natives (hazard ratio 6.88, 95% CI 1.37-34.64; P < .001).

CONCLUSION

In Native Americans of the American Southwest, SSc is increased in prevalence but is phenotypically similar to SSc in non-Natives. However, mortality due specifically to infection is increased in Native Americans with SSc.

Determination of T Cell Responses in Thai Systemic Sclerosis Patients

Objectives

This study is aimed at determining the role of T cells by assessing the numbers of IFN-γ- and IL-2-secreting T cells following stimulation with peptides derived from DNA topoisomerase-I protein in Thai SSc patients.

Methods

Fifty Thai SSc patients and 50 healthy controls (HC) joined this study. IFN-γ and IL-2 levels upon stimulation of T cells with 6 peptides derived from DNA topoisomerase-I protein were determined. Anti-nuclear antibodies (ANA) and anti-Scl-70 antibodies were determined by using the ELISA method.

Results

In SSc patients, we detected a significantly higher number of IFN-γ- and IL-2-secreting CD8⁺ T cells than IFN-γ- and IL-2-secreting CD4⁺ T cells after stimulation with pooled peptides derived from DNA topoisomerase-I protein. A similar percentage of CD4⁺IL-2⁺, CD4⁺IFN-γ⁺, and CD8⁺IL-2⁺ were detected following stimulation with DNA topoisomerase-I protein -in SSc patients with anti-Scl-70 antibody (SSc/anti-Scl-70⁺) and those without. In contrast, the amount of CD8⁺IFN-γ⁺ cells was significantly higher in SSc/anti-Scl-70⁺ than those without. Stimulation with individual peptides showed that CSLRVEHINLHPELD (sPep3; 15 amino acids; position 505-519 of DNA topoisomerase-I protein) was the optimal epitope that induced T cells secreting the highest levels of IFN-γ and IL-2. A higher percentage of IFN-γ⁺CD4⁺ T cells was detected in SSc/anti-Scl-70⁺ than those without the following stimulation with peptides 2 (amino acid position 475-486 [RAVALYFIDKLA] of protein DNA topoisomerase).

Conclusion

The results from this study emphasize the critical role of DNA topoisomerase-I peptides on the activation of T cells in SSc patients. The findings provide a better understanding of SSc's immunopathogenesis and may lead to the development of diagnostic tools and specific treatments for SSc in the future.

Updates on genetics in systemic sclerosis

Systemic sclerosis (SSc) is a complex disease, in which an interaction of genetic and environmental factors plays an important role in its development and pathogenesis. A number of genetic studies, including candidate gene analysis and genome-wide association study, have found that the associated genetic variants are mainly localized in noncoding regions in the expression quantitative trait locus and influence corresponding gene expression. The gene variants identified as a risk for SSc susceptibility include those associated with innate immunity, adaptive immune response, and cell death, while there are only few SSc-associated genes involved in the fibrotic process or vascular homeostasis. Human leukocyte antigen class II genes are associated with SSc-related autoantibodies rather than SSc itself. Since the pathways between the associated genotype and phenotype are still poorly understood, further investigations using multi-omics technologies are necessary to characterize the complex molecular architecture of SSc, identify biomarkers useful to predict future outcomes and treatment responses, and discover effective drug targets.

Prevalence of interstitial lung disease in polymyositis and dermatomyositis: A meta-analysis from 2000 to 2020

OBJECTIVE

Interstitial lung disease (ILD) is the most important prognostic factor for mortality in patients with polymyositis (PM) and dermatomyositis (DM), but the prevalence of ILD in PM/DM may vary between countries. The aim of this study was to determine the overall prevalence of ILD in global patients with PM/DM.

METHODS

We performed a systematic literature review of studies published from Jan 1, 2000 to April 30, 2020 on ILD and PM/DM. We extracted data and pooled the prevalence by using a random-effect model due to high heterogeneity. Heterogeneity was assessed by subgroup analysis and sensitivity analysis.

RESULTS

A total of 34 studies with 10,130 patients were included in our meta-analysis. Pooled data demonstrated that the global prevalence of ILD in patients with PM/DM was 0.41 (95% confidence interval [CI] 0.35-0.48). However, this prevalence varied with geographical locations and time trends. The prevalence of ILD in PM/DM was 0.5 (95% CI 0.42-0.57) in Asia, 0.23 (95% CI 0.15-0.31) in America, and 0.26 (95% CI 0.18-0.34) in Europe. A higher prevalence of ILD was reported in studies published in 2011-2015 (0.43, 95% CI 0.34-0.52) and 2016-2020 (0.45, 95% CI 0.35-0.54), compared with those published in 2000-2010 (0.27, 95% CI 0.16-0.39). The pooled prevalence of ILD in patients with DM, PM, and clinically amyopathic dermatomyositis subtype was 0.42 (95% CI 0.35-0.49), 0.35 (95% CI 0.27-0.42), and 0.53 (95% CI 0.32-0.74), respectively. Patients with anti-Jo-1 and anti-melanoma differentiation-associated gene 5 antibodies were more likely to develop ILD than other myositis-specific autoantibodies.

CONCLUSION

The global prevalence of ILD in patients with PM/DM was approximately 41% and the condition was predominant in Asians. This highlights potential genetic and environmental differences in the pathogenesis of ILD in patients with PM/DM. More studies are required to elucidate the specific associations.

Efficacy and safety of nintedanib in Asian patients with systemic sclerosis-associated interstitial lung disease: Subgroup analysis of the SENSCIS trial

BACKGROUND AND OBJECTIVE

In the SENSCIS trial in patients with systemic sclerosis-associated interstitial lung disease (SSc-ILD), nintedanib reduced the rate of decline in forced vital capacity (FVC) (mL/year) over 52 weeks by 44% in comparison with placebo, with manageable adverse events in most patients. We analyzed the efficacy and safety of nintedanib in patients of Asian race.

METHODS

Patients with SSc-ILD were randomized to receive nintedanib or placebo. The outcomes over 52 weeks were analyzed in Asian versus non-Asian patients.

RESULTS

Of the 288 patients in each treatment group, 62 (21.5%) in the nintedanib group and 81 (28.1%) in the placebo group were Asian; 90.2% of the Asian patients were enrolled in Asian countries. In the placebo group, the rate of FVC decline over 52 weeks was consistent between Asian and non-Asian patients (-99.9 and -90.6 mL/year, respectively). The effect of nintedanib on reducing the rate of FVC decline over 52 weeks was consistent between Asian (difference, 44.3 mL/year [95% CI: -32.8, 121.4]) and non-Asian patients (difference, 39.0 mL/year [95% CI: -5.1, 83.1]) (treatment-by-time-by-subgroup interaction, p = 0.91). Diarrhea was the most frequent adverse event and was reported in similar proportions of Asian and non-Asian patients in the nintedanib group (80.6% and 74.3%, respectively) and placebo group (28.4% and 32.9%, respectively).

CONCLUSIONS

In patients with SSc-ILD, nintedanib had a consistent benefit on slowing the progression of SSc-ILD in Asian and non-Asian patients, with a similar adverse event profile.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02597933.

Expression of the Autoantigen Topoisomerase-1 is Enriched in the Lung Tissues of Patients With Autoimmune Interstitial Lung Disease: A Case Control Study

BACKGROUND

Among the autoimmune rheumatic diseases, it is striking that autoantibodies targeting ubiquitously expressed proteins (eg, topoisomerase-1) associate with specific clinical complications (eg, interstitial lung disease [ILD]). It has been proposed that enriched antigen expression in inflamed target tissue may play a role in focusing the autoimmune response. We sought to determine whether topoisomerase-1 expression is enriched in lungs from patients with autoimmune/inflammatory diseases relative to normal lung.

METHODS

We used a 99-core lung tissue microarray (TMA) containing lung tissue from 40 patients with autoimmune inflammatory ILD (cases) and 46 control subjects with normal lungs. We stained the TMA with antibodies to compare topoisomerase-1 and CD8 expression between patients and control subjects and evaluated whether expression is enriched in specific cell types. Staining was analyzed, and statistical comparisons were performed.

RESULTS

Cases were more likely to have global topoisomerase-1 expression (53% vs 21%; P = 0.003), specifically in pneumocytes (47% vs 16%; P = 0.003) and stromal/immune cells (32% vs 5%; P = 0.002) compared with control subjects. CD8 cell density (223 cells/mm² vs 102 cells/mm² ; P = 0.018) was significantly higher in topoisomerase-1-positive lung tissues compared with topoisomerase-1-negative lung tissues. Interestingly, topoisomerase-1 expression was significantly more common in scleroderma compared with normal lung (67% vs 21%; P = 0.036) and was present more frequently in pneumocytes in these patients (67% vs 16%; P = 0.018).

CONCLUSIONS

Pulmonary expression of topoisomerase-1 is increased in the setting of autoimmune ILD relative to normal lung, specifically in pneumocytes. This may contribute to the amplification of pulmonary disease in patients with scleroderma with a loss of tolerance to topoisomerase-1.

Racial Disparities in Systemic Sclerosis

Racial and ethnic disparities in systemic sclerosis are abundant. The incidence, severity of end-organ manifestations, functional impairment, quality of life, and mortality of systemic sclerosis vary by ethnic group. This article summarizes such disparities and explores the role of socioeconomic status in their development and persistence.

Racial differences in systemic sclerosis disease presentation: a European Scleroderma Trials and Research group study

OBJECTIVES

Racial factors play a significant role in SSc. We evaluated differences in SSc presentations between white patients (WP), Asian patients (AP) and black patients (BP) and analysed the effects of geographical locations.

METHODS

SSc characteristics of patients from the EUSTAR cohort were cross-sectionally compared across racial groups using survival and multiple logistic regression analyses.

RESULTS

The study included 9162 WP, 341 AP and 181 BP. AP developed the first non-RP feature faster than WP but slower than BP. AP were less frequently anti-centromere (ACA; odds ratio (OR) = 0.4, P < 0.001) and more frequently anti-topoisomerase-I autoantibodies (ATA) positive (OR = 1.2, P = 0.068), while BP were less likely to be ACA and ATA positive than were WP [OR(ACA) = 0.3, P < 0.001; OR(ATA) = 0.5, P = 0.020]. AP had less often (OR = 0.7, P = 0.06) and BP more often (OR = 2.7, P < 0.001) diffuse skin involvement than had WP. AP and BP were more likely to have pulmonary hypertension [OR(AP) = 2.6, P < 0.001; OR(BP) = 2.7, P = 0.03 vs WP] and a reduced forced vital capacity [OR(AP) = 2.5, P < 0.001; OR(BP) = 2.4, P < 0.004] than were WP. AP more often had an impaired diffusing capacity of the lung than had BP and WP [OR(AP vs BP) = 1.9, P = 0.038; OR(AP vs WP) = 2.4, P < 0.001]. After RP onset, AP and BP had a higher hazard to die than had WP [hazard ratio (HR) (AP) = 1.6, P = 0.011; HR(BP) = 2.1, P < 0.001].

CONCLUSION

Compared with WP, and mostly independent of geographical location, AP have a faster and earlier disease onset with high prevalences of ATA, pulmonary hypertension and forced vital capacity impairment and higher mortality. BP had the fastest disease onset, a high prevalence of diffuse skin involvement and nominally the highest mortality.

HLA Expression Correlates to the Risk of Immune Checkpoint Inhibitor-Induced Pneumonitis

Tumor-infiltrating T cell rescue by programmed cell death receptor-1 (PD-1)/PD-1 ligand-1 (PD-L1) immune checkpoint blockade is a recommended treatment for malignant diseases, including metastatic non-small-cell lung cancer (mNSCLC), malignant melanoma (MM), head and neck, kidney, and urothelial cancer. Monoclonal antibodies (mAbs) against either PD-1 or PD-L1 are active agents for these patients; however, their use may be complicated by unpredictable immune-related adverse events (irAEs), including immune-related pneumonitis (IRP). We carried out a retrospective multi-institutional statistical analysis to investigate clinical and biological parameters correlated with IRP rate on a cohort of 256 patients who received real-world treatment with PD-1/PD-L1 blocking mAbs. An independent radiological review board detected IRP in 29 patients. We did not find statistical IRP rate correlation with gender, tumor type, specific PD-1 or PD-L1 blocking mAbs, radiation therapy, inflammatory profile, or different irAEs. A higher IRP risk was detected only in mNSCLC patients who received metronomic chemotherapy +/− bevacizumab compared with other treatments prior PD-1/PD-L1 blockade. Moreover, we detected a strong correlation among the IRP rate and germinal expression of HLA-B*35 and DRB1*11, alleles associated to autoimmune diseases. Our findings may have relevant implications in predicting the IRP rate in mNSCLC patients receiving PD-1/PD-L1 blockade and need to be validated on a larger patient series.

Clinical characteristics and outcomes of 566 Thais with systemic sclerosis: A cohort study

BACKGROUND

Most Thai patients with systemic sclerosis (SSc) have diffuse cutaneous SSc (dcSSc) unlike most Caucasians and some Asians. A longitudinal cohort study among Thai dcSSc is needed.

OBJECTIVES

We aimed to determine the overall clinical characteristics, define the clinical difference between limited cutaneous SSc (lcSSc) and dcSSc, and ascertain the mortality rate and the factors associated with mortality.

METHOD

We conducted a cohort study including 566 Thai adult SSc patients between January 2013 and June 2019. Clinical difference between lcSSc and dcSSc was investigated using generalized estimating equations (GEE).

RESULTS

Females presented more than males (356 vs 210 cases). The majority of cases were dcSSc (411; 72.6%). The median duration of disease at the time of pulmonary fibrosis (PF) detection was 2.5 years, pulmonary arterial hypertension 8.1 years, and renal crisis 4.1 years. By GEE analysis, dcSSc was significantly associated with salt-and-pepper skin, hand deformity, and every 1-point increase in modified Rodnan skin score (mRSS). A greater mortality risk was associated with age at onset >60 years (hazards ratio [HR] 5.5), a World Health Organization functional class (FC) III (HR 5.1), FC IV (HR 34.8), edematous skin (HR 11.4), early onset of PF (HR 1.7), each 5-point increase in the mRSS (HR 4.5), and ≥2 internal organ involvements (HR 10.1).

CONCLUSION

dcSSc is a common SSc subset among Thais. PF was an early complication in SSc and earlier PF detection was associated with a poorer prognosis. Elderly onset, high FC, severe skin tightness, and multiple organ involvements were associated with a greater mortality risk.

Identification of HLA-A/B/DRB1 alleles in Iranian patients with Fanconi anemia

Fanconi anemia includes a number of clinically and genetically diverse disorders all of them being associated with genomic instability. Some previous studies reported higher frequencies of certain HLA alleles in patients with Fanconi anemia. In the current study, we genotyped HLA-A/B/DRB1 alleles in 40 Iranian patients with Fanconi anemia. We also genotyped these alleles in the same number of Iranian sex-matched healthy individuals. The frequency of DRB1*11 was significantly higher in patients compared with controls (OR (95% CI) = 2.143 [1.05, 4.46], P value = 0.036). On the other hand, the frequencies of DRB1*13 and B*13 were lower in patients compared with controls (OR (95% CI) = 0.134 [0.02, 0.55], P value = 0.003 and OR (95% CI) = 0.13 [0.01, 0.89], P value = 0.035, respectively). Assessment of genetic divergence using Fstat test showed complete divergence in HLA-A, -B, -DRB1 alleles and haplotypes between patients and controls. The current study provides evidences for different distribution of HLA alleles between patients with Fanconi anemia and healthy subjects.

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.

Ethnic Variations in Systemic Sclerosis Disease Manifestations, Internal Organ Involvement, and Mortality

Objective.

A multiethnic systemic sclerosis (SSc) cohort study to evaluate ethnic variations in disease manifestations, internal organ involvement, and survival.

Methods.

Adults who fulfilled the American College of Rheumatology/European League Against Rheumatism classification criteria for SSc between 1970 and 2017 were included. Self-reported ethnicity was categorized as European-descent white, Afro-Caribbean, Hispanic, Arab, East Asian, South Asian, First Nations, or Persian. The primary outcome was the time from diagnosis to death from all causes. Survival probabilities and median survival times were determined using Kaplan-Meier survival curves.

Results.

There were 1005 subjects evaluated, the majority of whom were European-descent white (n = 745, 74%), Afro-Caribbean (n = 58, 6%), South Asian (n = 70, 7%), and East Asian (n = 80, 8%). Compared to European-descent white subjects, East Asians less frequently had calcinosis (29% vs 9%, p = 0.002) and esophageal dysmotility (88% vs 69%, p = 0.002); Afro-Caribbeans more frequently had interstitial lung disease (31% vs 53%, p = 0.007); and First Nations subjects more frequently had diffuse cutaneous disease (35% vs 56%, p = 0.02) and diabetes (5% vs 33%, p = 0.03). We found no difference in the short-term survival across ethnicities. Hispanic subjects have better longterm survival (81.3%, 95% CI 63–100) compared to European-descent white subjects (55%, 95% CI 51–60). East Asians appear to have the longest median survival time (43.3 yrs) and Arabs the shortest median survival time (15 yrs). There was no significant difference in median survival times between Afro-Caribbean and European-descent white subjects (22.2 vs 22.6 yrs).

Conclusion.

Ethnic variations in some SSc disease manifestations are observed. However, this does not result in significant differences in short-term survival but may affect longterm survival.

Interactions of HLA-DR and Topoisomerase I Epitope Modulated Genetic Risk for Systemic Sclerosis

The association of systemic sclerosis with anti-Topoisomerase 1 antibody (ATASSc) with specific alleles of human leukocyte antigen (HLA)-DR has been observed among various ethnics. The anti-Topoisomerase 1 antibody is a common autoantibody in SSc with diffuse cutaneous scleroderma, which is one of the clinical subtypes of SSc. On the other hand, an immunodominant peptide of topoisomerase 1 (Top1) self-protein (residues 349-368) was reported to have strong association with ATASSc. In this study, molecular dynamics simulation was performed on the complexes of Top1 peptide with various HLA-DR subtypes divided into ATASSc-associated alleles (HLA-DRB1*08:02, HLA-DRB1*11:01 and HLA-DRB1*11:04), suspected allele (HLA-DRB5*01:02), and non-associated allele (HLA-DRB1*01:01). The unique interaction for each system was compared to the others in terms of dynamical behaviors, binding free energies and solvation effects. Our results showed that three HLA-DR/Top1 complexes of ATASSc association mostly exhibited high protein stability and increased binding efficiency without solvent interruption, in contrast to non-association. The suspected case (HLA-DRB5*01:02) binds Top1 as strongly as the ATASSc association case, which implied a highly possible risk for ATASSc development. This finding might support ATASSc development mechanism leading to a guideline for the treatment and avoidance of pathogens like Top1 self-peptide risk for ATASSc.

Characterization of indigenous community engagement in arthritis studies conducted in Canada, United States of America, Australia and New Zealand

BACKGROUND

Research adhering to community engagement processes leads to improved outcomes. The level of Indigenous communities' engagement in rheumatology research is unknown.

OBJECTIVE

To characterize the frequency and level of community engagement reporting in arthritis studies conducted in Australia (AUS), Canada (CAN), New Zealand (NZ) and the United States of America (USA).

METHODS

Studies identified through systematic reviews on topics of arthritis epidemiology, disease phenotypes and outcomes, health service utilization and mortality in Indigenous populations of AUS, CAN, NZ and USA, were evaluated for their descriptions of community engagement. The level of community engagement during inception, data collection and results interpretation/dissemination stages of research was evaluated using a custom-made instrument, which ranked studies along the community engagement spectrum (i.e. inform-consult-involve-collaborate-empower). Meaningful community engagement was defined as involving, collaborating or empowering communities. Descriptive analyses for community engagement were performed and secondary non-parametric inferential analyses were conducted to evaluate the possible associations between year of publication, origin of the research idea, publication type and region of study; and meaningful community engagement.

RESULTS

Only 34% (n = 69) of the 205 studies identified reported community engagement at ≥ 1 stage of research. Nearly all studies that engaged communities (99% (n = 68)) did so during data collection, while only 10% (n = 7) did so at the inception of research and 16% (n = 11) described community engagement at the results' interpretation/dissemination stage. Most studies provided community engagement descriptions that were assessed to be at the lower end of the spectrum. At the inception of research stage, 3 studies reported consulting communities, while 42 studies reported community consultation at data collection stage and 4 studies reported informing or consulting communities at the interpretation/dissemination of results stage. Only 4 studies described meaningful community engagement through all stages of the research. Inferential statistics identified that studies with research ideas that originated from the Indigenous communities involved were significantly more associated with achieving meaningful community engagement.

CONCLUSIONS

The reporting of Indigenous community engagement in published arthritis studies is limited in frequency and is most frequently described at the lower end of the community engagement spectrum. Processes that support meaningful community engagement are to be promoted.

Late-onset nivolumab-mediated pneumonitis in a patient with melanoma and multiple immune-related adverse events

Immune-related adverse effects (AEs) of PD-1 inhibitors can affect almost every organ, but the skin, intestine, lung, eye, and liver are the most commonly affected organs. Here, we present the case of a 62-year-old female patient with stage IIIc melanoma treated with nivolumab in an adjuvant setting who sequentially developed hyperthyroidism, hypothyroidism, acute hepatitis, and pneumonitis. Six months before the emergence of pneumonitis, the patient had discontinued treatment with nivolumab because of acute hepatitis. Information on pneumonitis after nivolumab discontinuation in the literature is scarce, whereas most of the cases emerge during the first 2.5 months of treatment. Patients with multiple immune-related AEs comprise a group of special interest as the identification of factors affecting the susceptibility of patients to immune-related AEs of PD-1 inhibitors may lead to a more rational use of these drugs. Human leukocyte antigen haplotype and Fcγ receptor polymorphisms are possible targets of the relevant research.

Unique clinical characteristics, autoantibodies and medication use in Native American patients with systemic lupus erythematosus

Objective

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with varied morbidity and mortality. We assessed clinical presentations, autoantibody specificities and therapeutic interventions in Native American (NA) patients with SLE.

Methods

Patients with SLE meeting 1997 American College of Rheumatology classification criteria (n=3148) were enrolled between 1992 and 2010 in the multiethnic, cross-sectional Lupus Family Registry and Repository. Clinical, demographic and therapeutic information were extracted from medical records using a standardised form and formalised training. Autoantibodies were assessed by indirect immunofluorescence (antinuclear antibodies (ANA) and antidouble-stranded DNA), precipitin (ENA) and ELISA (IgG and IgM anticardiolipins).

Results

NA patients met SLE classification at a younger age (29.89±12.3 years) than European Americans (EA; 32.02±12.87, P=0.0157) and a similar age to African-Americans (AAs) and Hispanics (HIS). More NA patients had concurrent rheumatic diseases or symptoms, such as Raynaud’s phenomenon, interstitial lung disease, Sjӧgren’s syndrome and systemic sclerosis. Compared with EAs, NAs were more likely to have high-titre ANA (≥1:3240; P<0.0001) and had more SLE-associated autoantibodies. Autoantibodies with unknown specificities were more common in NAs (41%) compared with other racial/ethnic groups in this collection (AA: 24%, P=0.0006; EA: 17%, P<0.0001; HIS: 23%, P=0.0050). Fewer NA patients used hydroxychloroquine (68%) compared with others (AA: 74%, P=0.0308; EA: 79%, P=0.0001, HIS: 77%, P=0.0173); this was influenced by lower hydroxychloroquine use in NA patients from Latin America (32%). NA patients had higher rates of methotrexate use (28%) compared with AA (18%, P=0.0006) and HIS patients (14%, P=0.0003), higher azathioprine use (38%) compared with EA patients (30%, P=0.0105) and higher mycophenolate mofetil use (26%) compared with EA (17%, P=0.0012) and HIS patients (11%, P<0.0001).

Conclusions

NA patients are diagnosed with SLE earlier in life and present worse concurrent rheumatic disease symptoms than EA patients. NA patients also are more likely to have expanded autoantibody profiles and precipitins of unknown specificities.

Genetic predictors of systemic sclerosis-associated interstitial lung disease: a review of recent literature

The interplay between genetic and environmental factors is likely involved in the pathogenesis of systemic sclerosis (SSc). Interstitial lung disease associated in the context of SSc (SSc-ILD) is associated with significant morbidity, and is the leading cause of death in SSc. The spectrum of SSc-ILD severity is wide, ranging from patients with only limited and inherently stable pulmonary involvement, to those with extensive and progressive pulmonary fibrosis. In order to provide accurate prognostic information for patients, and to initiate appropriate monitoring and treatment regimens, the ability to identify patients at risk of developing severe ILD early in the disease course is crucial. Identification of genetic variants involved in disease pathogenesis can not only potentially provide diagnostic/prognostic markers, but can also highlight dysregulated molecular pathways for therapeutic targeting. A number of genetic associations have been established for susceptibility to SSc, but far fewer studies have investigated genetic susceptibility to SSc-ILD specifically. In this review we present a summary of the studies assessing genetic associations with SSc-ILD.

Mortality causes and outcomes in Indigenous populations of Canada, the United States, and Australia with rheumatic disease: A systematic review

BACKGROUND

Indigenous populations of Canada, America, Australia, and New Zealand have increased rates and severity of rheumatic disease. Our objective was to summarize mortality outcomes and explore disease and social factors related to mortality.

METHODS

A systematic search was performed in medical (Medline, EMBASE, and CINAHL), Indigenous and conference abstract databases (to June 2015) combining search terms for Indigenous populations and rheumatic diseases. Studies were included if they reported measures of mortality (crude frequency, mortality rate, survival, and potential years of life lost (PYLL)) in Indigenous populations from the four countries.

RESULTS

Of 5269 titles and abstracts identified, 504 underwent full-text review and 12 were included. No studies from New Zealand were found. In five Canadian studies of systemic lupus erythematosus (SLE) patients, First Nations ethnicity was associated with lower survival after adjusting for disease and social factors, and an increased frequency of death from lupus and its complications compared to Caucasians was found. All-cause mortality was higher in Native Americans (n = 2 studies) relative to Whites with SLE after adjusting for disease and social factors, but not in those with lupus nephritis alone. Australian Aborigines with SLE frequently developed infection and lupus complications leading to death (n = 3 studies). Mortality rates were increased in Pima Indians in the United States with rheumatoid arthritis (RA) compared to those without RA. One study in Native Americans with scleroderma found nearly all deaths were related to progressive disease.

CONCLUSIONS

Canadian and American Indigenous populations with SLE have increased mortality rates compared to Caucasian populations. Mortality in Canadian and Australian Indigenous populations with SLE, and in Native American populations with RA and scleroderma, is frequently attributed to disease progression or complications. The proportional attribution of rheumatic disease severity and social factors to mortality and complications leading to death between Indigenous and non-Indigenous populations has not been fully evaluated.

Systematic review of rheumatic disease phenotypes and outcomes in the Indigenous populations of Canada, the USA, Australia and New Zealand

We performed a systematic review designed to characterize clinical phenotypes and outcomes in Indigenous populations with rheumatic disease to enhance the understanding of how rheumatic disease presents in Indigenous populations and allow for better projection of the healthcare needs of the communities affected. A systematic search was performed in medical (Medline, EMBASE, CINAHL), Indigenous and conference abstract databases (to June 2015). Search terms for Indigenous populations were combined with terms for inflammatory arthritis conditions, connective tissue disorders, crystal arthritis and osteoarthritis. Studies were included if they reported on disease features, disease activity measures, or patient-reported outcomes in Canadian, American, Australian or New Zealand Indigenous populations. Data were extracted in duplicate, and a narrative summary was prepared. A total of 5269 titles and abstracts were reviewed, of which 504 underwent full-text review and 85 met inclusion criteria. Nearly all the studies described outcomes in the North American populations (n = 77), with only four studies from Australia and four studies from New Zealand. The majority of studies were in rheumatoid arthritis (n = 31) and systemic lupus erythematosus (n = 19). Indigenous patients with rheumatoid arthritis had higher disease activity and reported more significant impact on patient-reported outcomes and quality of life than non-Indigenous patients. Spondyloarthropathy features were described in North American populations, with most patients having advanced manifestations. In systemic lupus erythematosus, nephritis was more frequent in Indigenous populations. Gout and osteoarthritis were more severe in New Zealand Maori populations. The existing literature supports differences in disease phenotype and severity in Indigenous populations of Canada, America, Australia and New Zealand. We encourage investigators in this area of research to undertake contemporary studies that disentangle differences between phenotype and severity that are biologic in etiology or merely reflecting differences in access to care and that provide a longitudinal assessment of outcomes in more diverse populations.

Dermatologic conditions in patients of color who are pregnant

Certain dermatoses that present during pregnancy have a predilection for populations with skin of color (SOC). Additionally, certain systemic diseases such as systemic lupus erythematosus tend to be more aggressive during pregnancy and confer worse prognoses in women with SOC. The purpose of this review is to highlight the unique implications of selected diseases during pregnancy as it relates to SOC. Dermatologists should be vigilant for the unique clinical variations of dermatological conditions in patients of color who are pregnant to ensure correct diagnoses and optimize treatment outcomes.

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.

Negatively-charged amino acids at the peptide-binding pocket of HLA-DPB1 alleles are associated with susceptibility to anti-topoisomerase I-positive systemic sclerosis

We investigated shared characteristics of amino acid sequences in the at risk HLA-DPB1 alleles in systemic sclerosis (SSc). Amino acid sequences and their structural features of HLA-DP molecules in 127 Korean SSc patients and 548 healthy Korean controls were analyzed with a focus on known HLA-DP binding motifs. The binding grooves containing more negatively-charged triplets (NCT) had higher odds ratios of anti-topoisomerase I antibody (ATA)-positive SSc. In particular, the co-existence of a NCT at position 82-85 and more than one additional NCT were critical for increased risk of ATA-positive SSc. Molecular dynamic simulations showed that the model peptide with positive charge from topoisomerase I fits more closely into HLA-DP alleles possessing more NCTs. ATA-positive SSc patients share NCTs at the peptide-binding groove of HLA-DPB1 molecules.

Frequency of circulating topoisomerase-I-specific CD4 T cells predicts presence and progression of interstitial lung disease in scleroderma

Background

Scleroderma is an antigen-driven T cell-mediated autoimmune disease. Presence of anti-topoisomerase-I antibodies is associated with pulmonary fibrosis and predicts increased mortality. Characterization of autoreactive T lymphocytes may shed light on disease pathogenesis and serve as a biomarker for disease activity. Here, we aimed to quantify and functionally characterize circulating topoisomerase I (topo-I)-specific CD4+ T cells and to define their association with presence and progression of interstitial lung disease (ILD) in patients with scleroderma.

Methods

Using flow cytometry, circulating topo-I-reactive CD4+ T cells were identified by the expression of specific activation markers (CD154 and CD69) upon stimulation with purified topo-I and quantified in 27 SSc patients and 4 healthy donors (HD). Polarization of autoreactive T cells (Th1, Th2, Th17, Th1–17) was defined using surface expression of specific chemokine receptors. Presence and progression of ILD were determined using high-resolution chest CT and pulmonary function tests.

Results

Topo-I-reactive CD4+ T cells were found in all topo-I-positive patients compared to one topo-I-negative subject and no HD. Topo-I-specific CD4+ T cells exhibited a distinct Th17 polarized phenotype. Autoreactive T cells were significantly increased in subjects with evidence of ILD and were quantitatively associated with the decline of lung volumes.

Conclusions

Topo-I-specific T cells can be reliably quantified in the peripheral blood of patients with scleroderma, exhibit a pro-inflammatory Th17 phenotype, and predict progression of ILD.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-016-0993-2) contains supplementary material, which is available to authorized users.

Racial Disparities in Corneal Transplantation Rates, Complications, and Outcomes

Corneal transplantation is a common type of tissue transplantation that aims to improve vision or relieve pain. Given the immune privilege of the cornea, the primary graft often has a high success rate, approaching 90%. Despite the good overall outcome of corneal transplantation in various studies, the individual graft survival rate varies, depending on the preoperative diagnosis and donor and recipient factors. Race and ethnicity have been shown to be important in other types of organ transplantation. The aim of this study was to review the available ophthalmic literature regarding any differences in rates and outcomes of corneal transplantation based on ethnicity and race. A small body of evidence suggests that race might be an important risk factor for graft rejection and graft failure. More robust studies are needed to clarify these associations.

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.

Racial differences between blacks and whites with systemic sclerosis

PURPOSE OF REVIEW

Racial disparities appear to exist in the susceptibility and severity of systemic sclerosis (SSc, scleroderma) and are responsible for a greater health burden in blacks as compared with whites. Disparities in socioeconomic status and access to healthcare do not sufficiently explain the observed differences in prevalence and mortality. It is important to determine whether there might be a biologic basis for the racial disparities observed in SSc.

RECENT FINDINGS

We present data to suggest that the increased susceptibility and severity of SSc in blacks may result in part from an imbalance of profibrotic and antifibrotic factors. Racial differences in the expression of transforming growth factor-β1 (TGF-β1) and caveolin-1, as well as differences in the expression of hepatocyte growth factor and PPAR-γ, have been demonstrated in blacks with SSc, as well as in normal black individuals. A genetic predisposition to fibrosis may account for much of the racial disparities between black and white patients with SSc.

SUMMARY

A better understanding of the biologic basis for the racial disparities observed in SSc may lead to improved therapies, along with the recognition that different therapies may need to be adapted for different groups of patients.

Survival, Causes of Death, and Prognostic Factors in Systemic Sclerosis: Analysis of 947 Brazilian Patients

Objective.

To analyze survival, prognostic factors, and causes of death in a large cohort of patients with systemic sclerosis (SSc).

Methods.

From 1991 to 2010, 947 patients with SSc were treated at 2 referral university centers in Brazil. Causes of death were considered SSc-related and non-SSc-related. Multiple logistic regression analysis was used to identify prognostic factors. Survival at 5 and 10 years was estimated using the Kaplan-Meier method.

Results.

One hundred sixty-eight patients died during the followup. Among the 110 deaths considered related to SSc, there was predominance of lung (48.1%) and heart (24.5%) involvement. Most of the 58 deaths not related to SSc were caused by infection, cardiovascular or cerebrovascular disease, and cancer. Male sex, modified Rodnan skin score (mRSS) > 20, osteoarticular involvement, lung involvement, and renal crisis were the main prognostic factors associated to death. Overall survival rate was 90% for 5 years and 84% for 10 years. Patients presented worse prognosis if they had diffuse SSc (85% vs 92% at 5 yrs, respectively, and 77% vs 87% at 10 yrs, compared to limited SSc), male sex (77% vs 90% at 5 yrs and 64% vs 86% at 10 yrs, compared to female sex), and mRSS > 20 (83% vs 90% at 5 yrs and 66% vs 86% at 10 yrs, compared to mRSS < 20).

Conclusion.

Survival was worse in male patients with diffuse SSc, and lung and heart involvement represented the main causes of death in this South American series of patients with SSc.

Rheumatic disease among Oklahoma tribal populations: a cross-sectional study

OBJECTIVE

Rheumatic diseases cause significant morbidity within American Indian populations. Clinical disease presentations, as well as historically associated autoantibodies, are not always useful in making a rapid diagnosis or assessing prognosis. The purpose of our study was to identify autoantibody associations among Oklahoma tribal populations with rheumatic disease.

METHODS

Oklahoma tribal members (110 patients with rheumatic disease and 110 controls) were enrolled at tribal-based clinics. Patients with rheumatic disease (suspected or confirmed diagnosis) were assessed by a rheumatologist for clinical features, disease criteria, and activity measures. Blood samples were collected and tested for common rheumatic disease autoantibodies [antinuclear antibody (ANA), anti-cyclic citrullinated peptide antibodies (anti-CCP), rheumatoid factor (RF), anti-Ro, anti-La, anti-Sm, anti-nRNP, anti-ribosomal P, anti-dsDNA, and anticardiolipins].

RESULTS

In patients with suspected systemic rheumatic diseases, 72% satisfied American College of Rheumatology classification criteria: 40 (36%) had rheumatoid arthritis (RA), 16 (15%) systemic lupus erythematosus, 8 (7%) scleroderma, 8 (7%) osteoarthritis, 4 (4%) fibromyalgia, 2 (2%) seronegative spondyloarthropathy, 1 Sjögren's syndrome, and 1 sarcoidosis. Compared to controls, RA patient sera were more likely to contain anti-CCP (55% vs 2%; p < 0.001) or RF IgM antibodies (57% vs 10%; p < 0.001); however, the difference was greater for anti-CCP. Anti-CCP positivity conferred higher disease activity scores (DAS28 5.6 vs 4.45; p = 0.021) while RF positivity did not (DAS28 5.36 vs 4.64; p = 0.15). Anticardiolipin antibodies (25% of rheumatic disease patients vs 10% of controls; p = 0.0022) and ANA (63% vs 21%; p < 0.0001) were more common in rheumatic disease patients.

CONCLUSION

Anti-CCP may serve as a more specific RA biomarker in American Indian patients, while the clinical significance of increased frequency of anticardiolipin antibodies needs further evaluation.

Evaluation of a new multi-parallel line immunoassay for systemic sclerosis-associated antibodies in an Asian population

OBJECTIVES

To compare the SSc-line immunoassay (LIA) with conventional techniques of antibody detection, to evaluate its diagnostic utility and to describe clinical associations of antibodies in Asian SSc patients.

METHODS

Stored sera from patients with SSc (n = 68), SLE (n = 49), OA (n = 41) and normal controls (NCs, n = 32) were evaluated. Cohen's κ and Bland-Altman plots were used to evaluate agreement.

RESULTS

There was good agreement between LIA and ELISA for anti-Scl-70 (κ = 0.97), anti-CENPA (κ = 0.83), anti-CENPB (κ = 0.96) and anti-PmScl100 (κ = 1.00) (5.48-8.22% of values outside the 95% limits of agreement using Bland-Altman plots), and between LIA and IIF for anti-CENPA (κ = 0.81) and anti-CENPB (κ = 0.77) (P < 0.001). Using LIA, of 32 (32/68, 47%) SSc patients negative for anti-Scl-70 and anti-CENPA/B, 5 (5/32, 15%) were positive for anti-Ku, -Nor90, -fibrillarin and -RP155. Specificity of each antibody for SSc was at least 97% (vs OA/NC) and 94% (vs SLE), except for anti-Ro52 (63%). Anti-CENPB was associated with joint pain [odds ratio (OR) 0.17], interstitial lung disease (OR 0.24) and telangiectasia (OR 4.00) (P < 0.05). Anti-Ro60 was associated with pulmonary arterial hypertension (OR 3.89, P = 0.041).

CONCLUSION

The SSc-LIA has good agreement with conventional techniques for selected antibodies and has good diagnostic utility.

Validation of potential classification criteria for systemic sclerosis

OBJECTIVE

Classification criteria for systemic sclerosis (SSc; scleroderma) are being updated jointly by the American College of Rheumatology and European League Against Rheumatism. Potential items for classification were reduced to 23 using Delphi and nominal group techniques. We evaluated the face, discriminant, and construct validity of the items to be further studied as potential criteria.

METHODS

Face validity was evaluated using the frequency of items in patients sampled from the Canadian Scleroderma Research Group, 1000 Faces of Lupus, and the Pittsburgh, Toronto, Madrid, and Berlin connective tissue disease (CTD) databases. Patients with SSc (n = 783) were compared to 1,071 patients with diseases similar to SSc (mimickers): systemic lupus erythematosus (n = 499), myositis (n = 171), Sjögren's syndrome (n = 95), Raynaud's phenomenon (RP; n = 228), mixed CTD (n = 29), and idiopathic pulmonary arterial hypertension (PAH; n = 49). Discriminant validity was evaluated using odds ratios (ORs). For construct validity, empirical ranking was compared to expert ranking.

RESULTS

Compared to mimickers, patients with SSc were more likely to have skin thickening (OR 427); telangiectasias (OR 91); anti-RNA polymerase III antibody (OR 75); puffy fingers (OR 35); finger flexion contractures (OR 29); tendon/bursal friction rubs (OR 27); anti-topoisomerase I antibody (OR 25); RP (OR 24); fingertip ulcers/pitting scars (OR 19); anticentromere antibody (OR 14); abnormal nailfold capillaries (OR 10); gastroesophageal reflux disease symptoms (OR 8); antinuclear antibody, calcinosis, dysphagia, and esophageal dilation (all OR 6); interstitial lung disease/pulmonary fibrosis (OR 5); and anti-PM-Scl antibody (OR 2). Reduced carbon monoxide diffusing capacity, PAH, and reduced forced vital capacity had ORs of <2. Renal crisis and digital pulp loss/acroosteolysis did not occur in SSc mimickers (OR not estimated). Empirical and expert ranking were correlated (Spearman's ρ = 0.53, P = 0.01).

CONCLUSION

The candidate items have good face, discriminant, and construct validity. Further item reduction will be evaluated in prospective SSc and mimicker cases.

Association of hepatocyte growth factor promoter polymorphism with severity of interstitial lung disease in Japanese patients with systemic sclerosis

OBJECTIVE

To examine associations of single-nucleotide polymorphisms (SNPs) within genes for hepatocyte growth factor (HGF) and its receptor c-met with disease susceptibility and organ involvement in Japanese patients with systemic sclerosis (SSc).

METHODS

Four SNPs (HGF -1652 C/T, +44222 C/T, and +63555 G/T, and c-met -980 T/A) were analyzed in 159 SSc patients and 103 healthy control subjects with the use of a polymerase chain reaction-based assay. The influence of the HGF -1652 SNP on transcription activity was evaluated with a luciferase reporter assay and an electrophoretic mobility shift assay (EMSA).

RESULTS

There was no difference in the distribution of HGF/c-met SNPs between SSc patients and controls. HGF -1652 TT was found much more frequently in SSc patients with end-stage lung disease (ESLD) than in those without (41% versus 8%; P = 0.0004). This association was confirmed by a replication study involving a separate cohort of 155 SSc patients. Kaplan-Meyer analysis revealed that HGF -1652 TT carriers had a higher probability of developing ESLD than did CT or CC carriers. The HGF promoter carrying the HGF -1652 T allele had lower transcription activity than did the promoter carrying the C allele. EMSA showed the presence of a potential negative transcription regulator that binds specifically to the HGF promoter carrying a T allele at position -1652. Finally, TT carriers had a relative inability to increase circulating HGF levels even in the presence of advanced interstitial lung disease.

CONCLUSION

A SNP in the HGF promoter region may modulate the severity of interstitial lung disease by controlling the transcriptional efficiency of the HGF gene.

Clinical features of 405 Japanese patients with systemic sclerosis

We aimed to clarify the clinical features of Japanese patients with systemic sclerosis (SSc), especially with reference to organ involvement and autoantibodies. A cohort of 405 patients with SSc who attended our institution from 1973 to 2008 was identified retrospectively. Data on clinical features, including autoantibodies, organ involvement, and overlap of other connective tissue diseases, were obtained by following the medical records until 2009. The percentage of male patients during or after 1990 was greater than that before 1990 (3.9 vs. 10.6%, respectively). Limited cutaneous SSc (lSSc) was twice as frequent as diffuse cutaneous SSc (dSSc). About half of the patients had lung involvement (50.4%), while only 3.2% had scleroderma renal crisis. Male gender was associated with lung involvement, and dSSc was associated with most organ involvements except for pulmonary arterial hypertension (PAH). Anti-Scl-70 antibody was associated with lung or heart involvement, while anti-U1-RNP antibody was only associated with PAH. Conversely, patients with anti-centromere antibody had less organ involvement. SSc-Sjögren overlap syndrome was related to lSSc, further overlapping systemic lupus erythematosus (SLE), and less lung or heart involvement. In conclusion, these results not only confirmed previous reports but revealed several other findings, such as the increased proportion of male patients in recent years and the relationships between clinical features.

Autoantibody diagnostics in clinical practice

Disease associated autoantibodies (AAB) are important biomarkers not only to confirm the diagnosis of the respective systemic autoimmune disease but also to diagnose the disease at very early stages (mono- or oligosymptomatic manifestations) or to diagnose the respective disease without the typical clinical manifestations (atypical forms). A confirmation of the diagnosis in early stages is required, if patients should benefit from early therapeutic intervention. Furthermore, AAB determinations are used for prognostic purposes and for monitoring of disease activity or response to therapy. For the advancement of autoantibody diagnostics in clinical practice the following aspects have to be considered: (i) The search for novel clinically relevant AAB and the identification of autoantigenic targets of AAB broadened the spectrum of autoimmune diagnostics and permit the diagnosis of former idiopathic diseases. (ii) To obtain steady diagnostic variables of clinically relevant AAB, the evaluation studies have to be standardized. (iii) Several special features and novel developments of autoantibody diagnostics make correct interpretation of antibody test results increasingly difficult. (iv) Beside standardization of AAB detection methods and quality management efforts the improvement of autoantibody diagnostics depends on further development of diagnostic algorithms including cost-effective multiparametric analyses.

Frequent coexistence of anti-topoisomerase I and anti-U1RNP autoantibodies in African American patients associated with mild skin involvement: a retrospective clinical study

Introduction

The presence of anti-topoisomerase I (topo I) antibodies is a classic scleroderma (SSc) marker presumably associated with a unique clinical subset. Here the clinical association of anti-topo I was reevaluated in unselected patients seen in a rheumatology clinic setting.

Methods

Sera from the initial visit in a cohort of unselected rheumatology clinic patients (n = 1,966, including 434 systemic lupus erythematosus (SLE), 119 SSc, 85 polymyositis/dermatomyositis (PM/DM)) were screened by radioimmunoprecipitation. Anti-topo I-positive sera were also tested with immunofluorescence and RNA immunoprecipitation.

Results

Twenty-five (15 Caucasian, eight African American, two Latin) anti-topo I positive patients were identified, and all except one met the ACR SSc criteria. Coexistence of other SSc autoantibodies was not observed, except for anti-U1RNP in six cases. When anti-topo I alone versus anti-topo I + U1RNP groups were compared, African American (21% vs. 67%), overlap with SLE (0 vs. 50%; P = 0.009) or PM/DM (0 vs. 33%; P = 0.05) or elevated creatine phosphokinase (CPK) (P = 0.07) were more common in the latter group. In comparison of anti-topo I-positive Caucasians versus African Americans, the latter more frequently had anti-U1RNP (13% vs. 50%), mild/no skin changes (14% vs. 63%; P = 0.03) and overlap with SLE (0 vs. 38%; P = 0.03) and PM/DM (0 vs. 25%; P = 0.05).

Conclusions

Anti-topo I detected by immunoprecipitation in unselected rheumatology patients is highly specific for SSc. Anti-topo I coexisting with anti-U1RNP in African American patients is associated with a subset of SLE overlapping with SSc and PM/DM but without apparent sclerodermatous changes.

Gender and ethnicity differences in the prevalence of scleroderma-related autoantibodies

Autoantibodies to topoisomerase I (topo I), RNA polymerase III (RNAPIII), centromere, U3RNP/fibrillarin, Th, PM-Scl, and U1RNP found in scleroderma (SSc) are associated with unique clinical subsets. The effects of race and gender on autoantibody prevalence and clinical manifestations were examined. Autoantibodies in sera from 105 SSc (include 75 Caucasian, 24 African-American, 6 others; 89 females and 16 males) were analyzed by immunofluorescence and immunoprecipitation. Clinical information was from database. SSc-related autoantibodies seldom coexist except for anti-topo I and anti-U1RNP. Anti-topo I (35% vs 15%), anti-U3RNP (30% vs 3%, p = 0.0005), and anti-U1RNP (30% vs 13%) were more common in African-Americans vs Caucasians. Anti-centromere (17%) and anti-PM-Scl (only in 8% of female) were found only in Caucasians. In race/gender combination, all three African-American males had anti-topo I (p = 0.04). Anti-U3RNP (35% vs 3%, p = 0.0005) and anti-U1RNP were common in African-American females. In African-American, all nucleolar dominant staining sera had anti-U3RNP; nuclear pattern was topo I (50%), U1RNP (19%), and RNAPIII (13%). In Caucasian, nucleolar was anti-Th (43%) and PM-Scl (29%); nuclear pattern was RNAPIII (29%), topo I (24%), and U1RNP (18%). Anti-topo I, anti-RNAPIII, and anti-U3RNP were associated with diffuse SSc while anti-centromere, anti-Th, and anti-U1 with limited disease. Proximal scleroderma was less common in African-American with anti-topo I (38% vs 91% in Caucasian, p = 0.04). The production of SSc-related autoantibodies is gender and race dependent, and this can be highly relevant in understanding their clinical significance.

Prevalence of anti-histone antibodies, their clinical significance and correlation with other autoantibodies in a cohort of Italian scleroderma patients

Purpose

The aim of our study was to determine the prevalence, clinical significance of antibodies to individual histone components and to evaluate their correlation with other autoantibody specificities in a cohort of Italian SSc patients. Some authors, demonstrated high prevalence of anti-histone antibodies in Italian SSc patients, associated with cardiac and renal involvement, suggesting a prognostic value of these autoantibodies; however, these data need to be confirmed.

Methods

Serum from 112 adult SSc patients, classified as diffuse (dc) and limited cutaneous (lc) SSc subsets were analyzed for autoantibodies by indirect immunofluorescence, fluoroenzyme immunoassay and enzyme immunoassay.

Results

AHA were found in 13 patients (11.6%), nine with lcSSc and four with dcSSc. Among them, five patients were anti-Scl70+ and four were anti-CENP B+. The presence of AHA was not associated with multi-organ involvement or with diffuse subset, as already described. Anti-Scl70 was detected in 43% of patients, anti-CENP B in 32% and anti-RNA polymerase III in 7.1%. We confirmed the association between anti-Scl70 antibodies and pulmonary fibrosis (OR 15.75, p < 0.0001).

Conclusion

In our experience, the very low prevalence of AHA in Italian SSc patients and the lack of association with clinical manifestations suggest that this test is of little clinical use; however, it would be worthwhile extending the study to a larger population of patients.