Inflammatory stays inflammatory: a subgroup of systemic sclerosis characterized by high morbidity and inflammatory resistance to cyclophosphamide

Inflammatory Arthritis in Systemic Sclerosis: Its Epidemiology, Associations, and Morbidity

OBJECTIVE

To describe the epidemiology, associations, and impact of inflammatory arthritis (IA) in systemic sclerosis (SSc).

METHODS

Patients with SSc prospectively enrolled in the Australian Scleroderma Cohort Study were included. IA was defined clinically as the presence of synovitis on examination. Logistic regression was used to determine the associations of IA with SSc manifestations and serological parameters. Patient-reported outcome measures were used to capture physical function and health-related quality of life (HRQoL).

RESULTS

IA was a common SSc manifestation affecting one-third (33.3%) of patients over a median follow-up of 4.3 (1.7-8.4) years. Associations of IA included diffuse SSc (odds ratio [OR] 1.33, 95% confidence interval [95% CI] 1.01-1.74, P = 0.042), concurrent musculoskeletal manifestations (joint contractures and tendon friction rubs, OR 1.70, 95% CI 1.34-2.15, P < 0.001); myositis (OR 2.11, 95% CI 1.39-3.20, P < 0.001), and sicca symptoms (OR 1.57, 95% CI 1.14-2.16, P = 0.006), whereas IA was negatively associated with pulmonary arterial hypertension (OR 0.52, 95% CI 0.35-0.78, P = 0.002). Neither the presence of rheumatoid factor nor U1 small nuclear RNP were associated with IA (OR 1.13, 95% CI 0.88-1.44, P = 0.331, OR 1.46, 95% CI 0.89-2.39, P = 0.129 respectively). Positive anticyclic citrullinated protein antibodies, although at low frequency, were more common in those with IA compared with those without IA (7.5% vs 1.5%, P < 0.001). IA was associated with significantly lower HRQoL score (P < 0.001) and more physical disability than in those without IA (P < 0.001).

CONCLUSION

IA is a common disease manifestation that is more frquently seen in diffuse disease. IA is associated with poor HRQoL and physical disability. Further research is needed into the effective management of IA in SSc.

Serum levels of AGGF1: Potential association with cutaneous and cardiopulmonary involvements in systemic sclerosis

Systemic sclerosis (SSc) is an autoimmune disease characterized by vasculopathy, aberrant immune activation, and extensive tissue fibrosis of the skin and internal organs. Because of the complicated nature of its pathogenesis, the underlying mechanisms of SSc remain incompletely understood. Angiogenic factor with a G-patch domain and a Forkhead-associated domain 1 (AGGF1) is a critical factor in angiogenesis expressed on vascular endothelial cells, associated with inflammatory and fibrotic responses. To elucidate the possible implication of AGGF1 in SSc pathogenesis, we investigated the association between serum AGGF1 levels and clinical manifestations in SSc patients. We conducted a cross-sectional analysis of AGGF1 levels in sera from 60 SSc patients and 19 healthy controls with enzyme-linked immunosorbent assay. Serum AGGF1 levels in SSc patients were significantly higher than those in healthy individuals. In particular, diffuse cutaneous SSc patients with shorter disease duration had higher levels compared to those with longer disease duration and limited cutaneous SSc patients. Patients with higher serum AGGF1 levels had a higher incidence of digital ulcers, higher modified Rodnan Skin Scores (mRSS), elevated serum Krebs von den Lungen-6 (KL-6) levels, C-reactive protein levels, and right ventricular systolic pressures (RVSP) on the echocardiogram, whereas they had reduced percentage of vital capacity (%VC) and percentage of diffusing capacity of the lungs for carbon monoxide (%DLCO) in pulmonary functional tests. In line, serum AGGF1 levels were significantly correlated with mRSS, serum KL-6 and surfactant protein D levels, RVSP, and %DLCO. These results uncovered notable correlations between serum AGGF1 levels and key cutaneous and vascular involvements in SSc, suggesting potential roles of AGGF1 in SSc pathogenesis.

Phenotyping by persistent inflammation in systemic sclerosis associated interstitial lung disease: a EUSTAR database analysis

BACKGROUND

Systemic sclerosis (SSc) is a heterogeneous disease with frequently associated interstitial lung disease (SSc-ILD). We aimed to determine the prognostic potential of phenotyping patients with SSc and SSc-ILD by inflammation and to describe disease trajectories stratified by inflammation and immunosuppressive treatment.

METHODS

Patients from the European Scleroderma Trials and Research (EUSTAR) group cohort were allocated to persistent inflammatory, intermediate and non-inflammatory phenotypes if C-reactive protein (CRP) levels were ≥5 mg/L at ≥80%, at 20-80% and at <20% of visits, respectively. Cox regression models were used to analyse mortality risk and mixed effect models to describe trajectories of FVC and diffusing capacity for carbon monoxide (DLCO) %-predicted stratified by inflammation and immunosuppressive treatment.

RESULTS

2971 patients with SSc and 1171 patients with SSc-ILD had at least three CRP measurements available. Patients with SSc-ILD with a persistent inflammatory phenotype had a 6.7 times higher risk of mortality within 5 years compared with those with a persistent non-inflammatory phenotype (95% CI 3 to 15). In the inflammatory phenotype, FVC %-predicted was declining without (-1.11 (95% CI -2.14 to -0.08)/year), but stable with immunosuppressive treatment (-0.00 (95% CI -0.92 to 0.92)/year). In the non-inflammatory phenotype, patients with and without immunosuppressive treatment had a significant decline in FVC %-predicted, which was more pronounced in those with immunosuppressive treatment (-1.26 (95% CI -1.87 to -0.64) and -0.84 (95% CI -1.35 to -0.33)/year, respectively).

CONCLUSIONS

Phenotyping by persistent inflammation provides valuable prognostic information, independent of demographics, disease duration, cutaneous subtype, treatment and SSc-ILD severity. The findings from this study support early immunosuppressive treatment in patients with SSc-ILD with persistent inflammation.

The pentraxin family in autoimmune disease

The pentraxins represent a family of multifunctional proteins composed of long and short pentamers. The latter includes serum amyloid P component (SAP) and C-reactive protein (CRP) whereas the former includes neuronal PTX1 and PTX2 (NPTX1 and NPTX2, respectively), PTX3 and PTX4. These serve as a bridge between adaptive immunity and innate immunity and a link between inflammation and immunity. Similarities and differences between long and short pentamers are examined and their roles in autoimmune disease are discussed. Increased CRP and PTX3 could indicate the activity of rheumatoid arthritis, systemic lupus erythematosus or other autoimmune diseases. Mechanistically, CRP and PTX3 may predict target organ injury, regulate bone metabolic immunity and maintain homeostasis as well as participate in vascular endothelial remodeling. Interestingly, PTX3 is pleiotropic, being involved in inflammation and tissue repair. Given the therapeutic potential of PTX3 and CRP, targeting these factors to exert a beneficial effect is the focus of research efforts. Unfortunately, studies on NPTX1, NPTX2, PTX4 and SAP are scarce and more research is clearly needed to elaborate their potential roles in autoimmune disease.

Sudden cardiac death, arrhythmias and abnormal electrocardiography in systemic sclerosis: A systematic review and meta-analysis

OBJECTIVE

To calculate the frequency of sudden cardiac death(SCD), arrhythmia and conduction defects in SSc.

METHODS

MEDLINE/EMBASE were searched to January 2023. English-language studies reporting the incidence/frequency of SCD, arrhythmia and electrocardiography(ECG) abnormalities in SSc were included. Odds ratios(OR), estimations of annual incidence or pooled frequencies were calculated.

RESULTS

Seventy-nine studies(n = 13,609 participants with SSc) were included in the meta-analysis. Methodology and outcomes were heterogeneous. Ten studies included cohorts with known/suspected SSc-associated heart involvement(SHI), generally defined as clinically-manifest cardiac disease/abnormal cardiac investigations. The incidence of SCD in SHI was estimated to be 3.3% annually(n = 4 studies, 301PY follow-up). On ambulatory ECG, 18% of SHI cohorts had non-sustained ventricular tachycardia(NSVT; n = 4, 95%CI3.2-39.3%), 70% frequent premature ventricular complexes (PVCs; n = 1, 95%CI34.8-93.3%), and 8% atrial fibrillation (AF; n = 1, 95%CI4.2-13.6%). Nineteen studies included participants without SHI, defined as normal cardiac investigations/absence of cardiac disease. The estimated incidence of SCD was approximately 2.9% annually (n = 1, 67.5PY). Compared to healthy controls, individuals without SHI demonstrated NSVT 13.3-times more frequently (n = 2, 95%CI2-102), and paroxysmal supraventricular tachycardia 7-times more frequently (n = 4, 95%CI3-15). Other ambulatory ECG abnormalities included NSVT in 9% (n = 7, 95%CI6-14%), >1000 PVCs/24 h in 6% (n = 2, 95%CI1-13%), and AF in 7% (n = 5, 0-21%). Fifty studies included general SSc cohorts unselected for cardiac disease. The incidence of SCD was estimated to be 2.0% annually(n = 4 studies, 1646PY). Unselected SSc cohorts were 10.5-times more likely to demonstrate frequent PVCs (n = 2, 95%CI 2-59) and 2.5-times more likely to have an abnormal electrocardiography (n = 2, 95%CI1-4).

CONCLUSIONS

The incidence of SCD in SSc is estimated to be 1.0-3.3% annually, at least 10-fold higher than general population estimates. Arrhythmias including NSVT and frequent PVCs appear common, including amongst those without known/suspected SHI.

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.

Systemic sclerosis

Systemic sclerosis, also known as scleroderma, is a rare and complex autoimmune connective-tissue disease. Once considered an untreatable and unpredictable condition, research advancements have improved our understanding of its disease pathogenesis and clinical phenotypes and expanded our treatment armamentarium. Early and accurate diagnosis is essential, while ongoing efforts to risk stratify patients have a central role in predicting both organ involvement and disease progression. A holistic approach is required when choosing the optimal therapeutic strategy, balancing the side-effect profile with efficacy and tailoring the treatment according to the goals of care of the patient. This Seminar reviews the multiple clinical dimensions of systemic sclerosis, beginning at a precursor very early stage of disease, with a focus on timely early detection of organ involvement. This Seminar also summarises management considerations according to the pathological hallmarks of systemic sclerosis (eg, inflammation, fibrosis, and vasculopathy) and highlights unmet needs and opportunities for future research and discovery.

Systemic sclerosis

Systemic sclerosis, also known as scleroderma, is a rare and complex autoimmune connective-tissue disease. Once considered an untreatable and unpredictable condition, research advancements have improved our understanding of its disease pathogenesis and clinical phenotypes and expanded our treatment armamentarium. Early and accurate diagnosis is essential, while ongoing efforts to risk stratify patients have a central role in predicting both organ involvement and disease progression. A holistic approach is required when choosing the optimal therapeutic strategy, balancing the side-effect profile with efficacy and tailoring the treatment according to the goals of care of the patient. This Seminar reviews the multiple clinical dimensions of systemic sclerosis, beginning at a precursor very early stage of disease, with a focus on timely early detection of organ involvement. This Seminar also summarises management considerations according to the pathological hallmarks of systemic sclerosis (eg, inflammation, fibrosis, and vasculopathy) and highlights unmet needs and opportunities for future research and discovery.

Inflammatory arthritis in systemic sclerosis is associated with elevated C-reactive protein and requires musculoskeletal ultrasound for reliable detection

Objectives

About 25% of patients with systemic sclerosis (SSc) have elevated C-reactive protein (CRP) levels. Specific causes of CRP elevation are unknown so far. We aimed to investigate whether inflammatory arthritis is associated with CRP elevation. Furthermore, we evaluated the sensitivity and specificity of clinical examination compared to musculoskeletal ultrasound (MSUS) for detection of arthritis.

Methods

Sixty-five patients with SSc (51 females) were enrolled and allocated into a CRP-positive (CRP+, n = 20; CRP elevated for at least two years prior to enrollment) and a CRP-negative (CRP-; n = 45) cohort. All patients were examined clinically (modified Rodnan Skin Score, mRSS; swollen/tender joint count 66/68), received a comprehensive MSUS of their hands and feet, as well as laboratory testing (antibody status; CRP). Statistical analyses were performed using non-parametrical tests without adjustments.

Results

Patient with a disease duration <3 years had higher CRP levels (p = 0.042). Anti-centromere antibodies dominated in CRP- patients (p = 0.013), and anti-Scl70 antibodies in CRP + patients (p = 0.041). Joint effusion and B-mode synovitis prevailed in male (p < 0.00001; p < 0.0001) and CRP + (p = 0.001; p < 0.00001) patients. Power Doppler (PD)-synovitis predominated in patients with diffuse SSc (p = 0.0052). Joint effusion and B-/PD-synovitis were mostly confined to wrists, MTPs and talo-navicular joints. Compared to MSUS, sensitivity of clinical examination was as low as 14.6%; specificity was 87.7%. Sensitivity was reduced by the presence of soft tissue edema or a mRSS > 10.

Conclusion

Arthritis is more frequent in CRP + compared to CRP- SSc patients. Compared to MSUS sensitivity of clinical examination is low for the detection of arthritis; this is likely due to skin fibrosis and soft tissue edema. Therefore, regular monitoring via MSUS should be considered as routine assessment in SSc patients.

Anemia Is an Indicator for Worse Organ Damage Trajectories in Patients with Systemic Sclerosis: A Retrospective Study

It is important for clinicians to determine the risk of worsening trajectories in SSc patients. The Scleroderma Clinical Trials Consortium (SCTC) Damage Index (DI) has been developed to quantify organ damage and shows good capability for mortality and morbidity prediction in patients with SSc. This retrospective study aimed to describe the SCTC-DI in Chinese SSc patients and to find features predicting worse organ damage trajectories based on SCTC-DI. A total of 433 SSc patients who met the inclusion criteria in the Peking University Third Hospital (PKUTH-SSc) and People’s Hospital SSc cohort (PKUPH-SSc) were recruited for our study. Organ damage was relatively mild in our Chinese SSc cohort compared to other cohorts, with a mean SCTC-DI of 5.21 ± 4.60. We used both SCTC-DI ≥ 6 and ≥4 to define the high burden of organ damage and established two risk models by the LASSO algorithm, which revealed good identification of high organ damage burden (AUC = 0.689, 95% CI 0.636 to 0.742, p < 0.001 in SCTC-DI ≥ 6 model; AUC = 0.694, 95% CI 0.641 to 0.746, p < 0.001 in modified SCTC-DI ≥ 4 model). The anemia index at the baseline was included in these two models and was also independently related to organ damage progression (HR = 1.75, 95% CI 1.16 to 2.66, p = 0.008). In addition, the presence of an anti-Scl-70 autoantibody was also a predictor of progression (HR = 1.91, 95% CI 1.22 to 2.99, p = 0.005). In conclusion, anemia at the baseline was an important indicator for worse organ damage trajectories in SSc patients. We recommend using hemoglobin as a potential biomarker to evaluate organ damage in SSc patients.

C-reactive protein and ground-glass opacity as predictors for intractable interstitial lung disease in patients with systemic sclerosis under cyclophosphamide treatment regardless of concomitant glucocorticoids

OBJECTIVES

Cyclophosphamide (CYC) has been proposed as a standard induction regimen for interstitial lung disease (ILD) associated with systemic sclerosis (SSc). However, there remain patients with SSc-ILD who are intractable to the therapy. This study aimed to identify factors associated with inadequate response to CYC and investigate how to treat SSc-ILD, especially in the need for glucocorticoids (GCs) combined with CYC.

METHODS

This retrospective study included consecutive patients diagnosed with SSc-ILD and treated with CYC between 2009 and 2020. Logistic regression models were used to determine the prognostic factors indicating significant progression of ILD (SP-ILD). The clinical findings of patients treated with vs. without GCs were compared.

RESULTS

Nineteen patients were registered, with a median age of 61.0 years. Fifteen were females, and five were classified into SP-ILD. Baseline high C-reactive protein (CRP) levels and non-widespread or localized ground-glass opacities (GGOs) predicted SP-ILD in multivariable analyses, and the cut-off level of CRP was 0.41 mg/dL. In clinical courses, SSc-ILD with high inflammation temporarily responded to CYC, regardless of the combined use of GCs; however, the therapeutic effects deteriorated soon after stopping CYC.

CONCLUSION

High CRP levels with non-widespread GGO predicted progressive ILD in patients with SSc treated with CYC.

Systemic Sclerosis in Zimbabwe: Autoantibody Biomarkers, Clinical, and Laboratory Correlates

Introduction

Systemic sclerosis (SScl) is an autoimmune disease whose prevalence is rarely reported in Africa. Autoantibodies are the biomarkers of the condition, precede overt disease and determine disease phenotypes. SSc specific autoantibodies also vary between racial groupings. Objective: To investigate the clinical and laboratory characteristics of Zimbabwean patients who were reactive SSc specific autoantibodies.

Materials and Method

240 patients, 173 of them female with SSc specific autoantibodies were included. Autoantibodies were detected by indirect immunofluorescence microscopy and immunoblotting using a panel of 13 SScl (Euroimmun Ag., Germany). Demographic, clinical and laboratory parameters relevant to the monitoring of SScl were captured. These included pulmonary function tests, hematology, clinical chemistry, serology and thyroid function tests. Allergy skin prick tests (SPT) to inhalant and food allergen sources were conducted when indicated.

Results

All the 240 patients (median age was 36 years) expressed SSc specific autoantibodies. 86% were Black, 11% White and 3% Asian and a fifth (20%) were younger than 16 years. Eleven (4.6%) fulfilled the ACR/EULAR classification of SSc. Clinically they had limited cutaneous (n=6), diffuse cutaneous (n=3) and SScl/inflammatory myopathy overlap (n=2). The most frequently detected antibodies anti-RNA polymerase III (RNAP) 55%, anti-Th/To (28%) anti-RNAP 11 (22%), anti-CENPB (18%) and anti-Scl-70/ATA (13%). Racial variations in the expression of these antibodies were apparent between Black, White and Asian patients. The majority (95%), who did not fulfil the ARA/EULAR criteria were symptomatic. Raynaud’s Phenomenon was documented in 24%. Respiratory symptoms included coughing, dyspnea and wheezing. There was a restrictive ventilatory defect with increased FEV1/FVC ratio. Pruritus, urticaria and skin depigmentation were the main cutaneous features while constipation, bloating, Gastroesophageal reflux disease (GERD) and abdominal pain dominated GI symptoms. Mean blood pressure readings while normal varied with biomarkers. Haematology and biochemistry parameters were within normal reference ranges.

Conclusion

The expression of SSc specific autoantibodies is common and associated with known SSc symptoms. The types and frequency of autoantibodies varied with racial groupings. A fifth of the patients were children below the age of 16 years.

Epidemiology and clinical characteristics of systemic sclerosis overlap syndrome (SSc-OS), and the factors significantly associated with SSc-OS in Thai patients with systemic sclerosis

OBJECTIVE

To investigate the epidemiology and characteristics of systemic sclerosis (SSc) overlap syndrome (SSc-OS).

METHODS

This study included patients enrolled in the Siriraj Systemic Sclerosis Cohort registry during November 2013 to September 2019. SSc-OS was defined as SSc patients who also met criteria for rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), dermatomyositis (DM), polymyositis (PM), Sjogren, and/or antiphospholipid antibody syndrome. Baseline and 1-year characteristics were compared between SSc and SSc-OS.

RESULTS

185 patients (age 50.3 ± 11.4 years, 85.4% female, disease duration 2.7 years, 75.1% diffuse cutaneous subset, 75.6% anti-Scl-70 positivity) were included. The incidence and prevalence rate of SSc-OS was 3.2/100 patient-years and 17.8%. Regarding SSc-OS, 12.4%, 2.2%, 1.1%, 1.6%, and 0.5% of patients were classified as SSc-RA, SSc-SLE, SSc-PM, SSc-RA-SLE, and SSc-SLE-PM. SSc-OS had a higher prevalence of limited cutaneous subset (lcSSc), usual interstitial pneumonia, finger contractures, ESR >20 mm/hr., globulin >3.5 g/dL, rheumatoid factor, anti-citrullinated peptide antibody, and antiphospholipid antibodies. LcSSc subset (OR: 11.3, 95%CI: 2.0-62.6) and globulin >3.5 g/dL (OR: 6.2, 95%CI: 1.6-23.6) were associated with SSc-OS.

CONCLUSION

SSc-OS is associated with the lcSSc subset. RA is the most common overlap syndrome. LcSSc patients with globulin >3.5 g/dL are associated with SSc-OS.

Anti-IL-6 Therapy Effect for Refractory Joint and Skin Involvement in Systemic Sclerosis: A Real-world, Single Center Experience

OBJECTIVE

To examine the efficacy and safety of interleukin-6 inhibition by tocilizumab in difficult-to-treat real-world patients with Systemic Sclerosis (SSc).

METHODS

Twenty-one patients [20 women, 16 diffuse SSc, mean age: 52±10 years, 10 with early (<5 years) and 11 with long-standing disease (mean disease duration: 6.4±3.7 years)] with active joint and/or skin involvement refractory to corticosteroids (n=21), methotrexate (n=19), cyclophosphamide (n=10), mycophenolate (n=7), rituximab (n=1), leflunomide (n=2), hydroxychloroquine (n=2), and hematopoietic stem cell transplantation (n=2) who received weekly tocilizumab (162 mg subcutaneously) in an academic center, were monitored prospectively. Changes in modified Rodnan skin score (mRSS), disease activity score (DAS)28, lung function tests (LFTs) and patient reported outcomes (PROs) were analyzed after one year of treatment and at follow-up end.

RESULTS

One patient discontinued tocilizumab after 3 months due to inefficacy. During the first year of treatment, improvement was evident in the remaining 20 patients regarding skin involvement (mean mRSS change: -6.9±5.9,p<0.001), polyarthritis (mean DAS28 change: -1.9±0.8,p<0.001) and PROs (all p<0.001); LFTs stabilization was observed in 16/20 patients. During the second year, 3 patients discontinued tocilizumab (cytomegalovirus infection in 1, inefficacy in 2) and one died. Beneficial effects were sustained in all 16 patients at follow-up end (2.2±1.1 years), except LFTs deterioration in 3. Apart from recurrent digital ulcer infection in 3 patients, tocilizumab was well-tolerated.

CONCLUSION

Tocilizumab was effective in refractory joint and skin involvement irrespective of SSc disease duration or subtype. Long-term retention rates and disease stabilization for most real-world patients suggest that tocilizumab might be a valuable choice for difficult-to-treat SSc.

Prevalence and clinical association with calcinosis cutis in early systemic sclerosis

OBJECTIVES

Calcinosis cutis is often found with systemic sclerosis (SSc). However the calcinosis cutis and its clinical association among SSc patients is limited. Our aims were to assess the prevalence of calcinosis cutis and its association with clinical features of SSc patients at early onset of the disease.

METHODS

A cross-sectional study on clinical characteristics and hand radiographs of 120 newly diagnosed SSc patients with the onset less than four years were evaluated. Calcinosis cutis was described based on the anatomical regions, density (level 1-3) and shapes (net, plate, stone, and amorphous).

RESULTS

Among all SSc patients enrolled, 62.5% were females and 56.1% were diffuse cutaneous SSc. The mean disease duration was 2.0 ± 1.3 years. Calcinosis cutis was detected in 60 patients with the prevalence of 50% (95%confidence interval (CI), 0.41-0.59), of which 53.3% occurred at distal phalanx, 96.7% had stone shape and 48.3% were high density. Univariate analysis revealed that calcinosis cutis was associated with age (p = .02) and high-density calcinosis cutis was associated with Raynaud's phenomenon (p = .02), ischemic ulcer (p = .04), and telangiectasis (p = .02). Logistic regression analysis revealed that calcinosis cutis at distal phalanx was negatively associated with edema at the onset (odds ratio, 0.09).

CONCLUSION

Occult calcinosis cutis can be detected by hand radiograph in one half of SSc patients at early onset of the disease. Elderly patient has a risk for calcinosis cutis development and Raynaud's phenomenon was associated with high density calcinosis cutis. Calcinosis cutis, particularly at distal phalanx was less likely to be detected in an edematous phase of disease.

Metabolic Pattern of Systemic Sclerosis: Association of Changes in Plasma Concentrations of Amino Acid-Related Compounds With Disease Presentation

OBJECTIVE

Amino acids (AA) and their derivatives play an integral role in the synthesis of structural and regulatory elements in human organisms and therefore pathologies such as systemic sclerosis that may alter the blood pattern of these compounds. This study aimed to evaluate changes in plasma concentrations of amino acid-related metabolites in systemic sclerosis in a search for potential biomarkers and mechanisms of the disease.

METHODS

Plasma samples from 42 patients diagnosed with systemic sclerosis (SSc) according to the 2013 American College of Rheumatology and European League Against Rheumatism ACR/EULAR classification criteria were compared to 27 matched healthy controls. Liquid chromatography/mass spectrometry was applied for the analysis of 36 amino acid-related metabolites.

RESULTS

The analysis of plasma AA metabolite patterns revealed the number of changes including an increase (20%) in concentrations of NO synthase (NOS) inhibitor asymmetric dimethylarginine (ADMA) in SSc vs. healthy subjects. Furthermore, SSc patients had higher glutamine, proline, betaine, 1-methylhistidine, and methylnicotinamide levels, while the concentration of tryptophan was lower. The specific metabolic pattern was identified for several aspects of disease presentation. Most interestingly NOS inhibitor L-NAME was elevated in patients with diffuse systemic sclerosis or telangiectasia.

CONCLUSIONS

These results provide further evidence for the involvement of endothelium-dependent pathways in the mechanisms and presentation of SSc. Endothelial dysfunction biomarkers may be useful in the assessment of presentation and prognosis in SSc.