Diffusing Capacity of the Lungs for Carbon Monoxide and Echocardiographic Parameters in Identifying Mild Pulmonary Hypertension in the EUSTAR Cohort of Patients With Systemic Sclerosis.

BACKGROUND: The 2022 European Society of Cardiology/European Respiratory Society guidelines define pulmonary hypertension (PH) as a resting mean pulmonary artery pressure (mPAP) > 20 mm Hg at right heart catheterization (RHC). Previously, patients with an mPAP between 21 and 24 mm Hg were classified in a "gray zone" of unclear clinical significance. RESEARCH QUESTION: What is the diagnostic performance of the main parameters used for PH screening in detecting patients with systemic sclerosis (SSc) with an mPAP of 21 to 24 mm Hg at RHC? STUDY DESIGN AND METHODS: Patients with SSc from the European Scleroderma Trials and Research (EUSTAR) database with available tricuspid annular plane systolic excursion (TAPSE), systolic PAP (sPAP), and mPAP data were included. Patients with mPAP 21 to 24 mm Hg and patients with mPAP ≤ 20 mm Hg were considered for the analysis. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated. RESULTS: TAPSE/sPAP was lower in the group of patients with SSc with mPAP 21 to 24 mm Hg than in the non-PH group (0.58 [0.46-0.72] vs 0.69 [0.57-0.81] mm/mm Hg, respectively; P < .01). No difference was found in other parameters between the two groups. Diffusing capacity of the lungs for carbon monoxide (Dlco) < 80% of the predicted value had the highest sensitivity (88.9%) and NPV (80%), but the lowest specificity (18.2%) and PPV (30.8%) in detecting patients with SSc with mPAP 21 to 24 mm Hg. TAPSE/sPAP < 0.55 mm/mm Hg had the highest specificity (78.9%), PPV (50%), and accuracy (68.1%); its NPV was 75.4%, and its sensitivity was 45.1%. INTERPRETATION: Dlco < 80% of the predicted value is the parameter with the highest sensitivity and NPV in detecting patients with SSc with mPAP 21 to 24 mm Hg. TAPSE/sPAP < 0.55 mm/mm Hg has the highest specificity, PPV, and accuracy and, therefore, can be a useful additional parameter to decrease the number of unnecessary RHCs.

Iloprost infusion reduces serological cytokines and hormones of hypoxia and inflammation in systemic sclerosis patients.

INTRODUCTION: Systemic sclerosis (SSc) is characterized by microvascular damage of skin and internal organs with chronic hypoxia and release of cytokines and hormones such as neutrophil gelatinase-associated lipocalin (NGAL), fibroblast growth factor-23 (FGF-23) and Klotho. Aim of the study was to evaluate FGF-23, Klotho and NGAL serum levels in SSc patients and healthy controls (HC) and to evaluate serum levels changes of FGF-23, Klotho and NGAL after Iloprost. METHODS: Twenty-one SSc patients and 20 HC were enrolled. In SSc patients, peripheral venous blood samples were collected at the first day before the autumn Iloprost infusion (t0), 60 min (t1) and 14 days after Iloprost infusion (t2). RESULTS: SSc patients had higher serum level of FGF-23 [18.7 ± 6.4 pg/ml versus 3.6 ± 2.2 pg/ml, p < 0.001], Klotho [5.1 ± 0.8 pg/ml versus 2.3 ± 0.6 pg/ml, p < 0.001] and NGAL [20.9 ± 2.6 pg/ml versus 14.5 ± 1.7 pg/ml, p < 0.001] than HC. Iloprost infusion reduces serum level of FGF-23 (18.7 ± 6.4 pg/ml versus 10.4 ± 5.5 pg/ml, p < 0.001), Klotho (5.1 ± 0.8 pg/ml versus 2.5 ± 0.6 pg/ml, p < 0.001) and NGAL (20.9 ± 2.6 pg/ml versus 15.1 ± 2.3 pg/ml, p < 0.001) between t0 and t1. The Iloprost infusion reduces serum level of FGF-23 (18.7 ± 6.4 pg/ml versus 6.6 ± 5.1 pg/ml), Klotho (5.1 ± 0.8 pg/ml versus 2.3 ± 0.4 pg/ml) and NGAL (20.9 ± 2.6 pg/ml versus 15.5 ± 1.9 pg/ml) between t0 and t2. CONCLUSIONS: SSc patients had higher FGF-23, Klotho and NGAL than HC. Iloprost reduces serum levels of FGF-23, Klotho and NGAL.

In Systemic Sclerosis Patients, Peripheral Blood CD21low B Cells and Serum IL-4 and IL-21 Influence Joint Involvement.

Systemic sclerosis (SSc) patients have an increased frequency of CD21low B cells and of serum interleukin-4 (IL-4) and IL-21, each possible markers of joint involvement in inflammatory arthritis. The aim of this study was to investigate the possible influence of CD21low B cells, IL-4, and IL-21 on joint involvement in a cohort of 52 SSc patients. The DAS28-ESR was correlated with CD21low B cells (r = 0.452, p < 0.001), IL-4 (r = 0.478, p < 0.001), and IL-21 (r = 0.415, p < 0.001). SSc patients with a DAS28-ESR > 3.2 had more CD21low B cells (12.65% (IQR: 7.11-13.79) vs. 5.08% (IQR: 3.76-7.45), p < 0.01), higher IL-4 levels (132.98 pg/mL (IQR: 99.12-164.12) vs. 100.80 pg/mL (IQR: 62.78-121.13), p < 0.05), and higher IL-21 levels (200.77 pg/mL (IQR: 130.13-302.41) vs. 98.83 pg/mL (IQR: 35.70-231.55), p < 0.01) than patients with a DAS28-ESR ≤ 3.2. The logistic regression analysis models showed that the DAI (OR: 2.158 (95% CI: 1.120; 4.156), p < 0.05) and CD21low B cells (OR: 1.301 (95% CI: 1.099; 1.540), p < 0.01), the DAI (OR: 2.060 (95% CI: 1.082; 3.919), p < 0.05) and IL-4 level (OR: 1.026 (95% CI: 1.006; 1.045), p < 0.01), and the DAI (OR: 1.743 (95% CI: 1.022; 2.975), p < 0.05) and IL-21 level (OR: 1.006 (95% CI: 1.000; 1.011), p < 0.05) were independently associated with a DAS28-ESR > 3.2. An elevated CD21low B cell percentage, IL-4 level, and IL-21 level was associated with higher articular disease activity in patients, suggesting a possible role in the pathogenesis of SSc joint involvement.

GLIM-diagnosed malnutrition predicts mortality and risk of hospitalization in systemic sclerosis: A retrospective study.

BACKGROUND: Malnutrition is a well-known risk factor for morbidity and mortality in many clinical settings and only few studies assessed the role of malnutrition on systemic sclerosis (SSc) patients' outcomes. The aim of this retrospective study was to evaluate the role of malnutrition as a predictive risk factor for mortality and/or hospitalization in SSc patients during a 4-year follow-up. METHODS: One hundred and one SSc patients were included in the study. Biochemical analyses, disease activity index, disease severity scale and anthropometric data were recorded at enrollment. Malnutrition was assessed by the Global Leadership Initiative on Malnutrition (GLIM) criteria. RESULTS: Malnutrition according to GLIM criteria was found in 22 patients (21.8%). During a 4-year follow-up, 20 (19.8%) SSc patients died or were hospitalized for all causes and 11 of them (55.0%) were malnourished. Kaplan-Meier curves showed that event free-survival for composite end-point of mortality and risk of hospitalization was significantly shorter in malnourished than in non-malnourished patients (p<0.001). The survival probability at 4 years was 0.885 (95% CI=0.818-0.959) in the non-malnourished group and 0.500 (95% CI=0.329-0.759) in the malnourished group (p<0.001). In multivariate analysis, malnutrition [HR=4.380 (95% CI=1.706-11.243), p = 0.002] was the most significant predictive risk factor for the composite end-point. Also, female gender [HR=0.157 (95% CI=0.055-0.449), p<0.001], age [HR=1.0450 (95% CI=1.011-1.090), p = 0.012] and disease severity scale [HR=1.269 (95% CI=1.089-1.479), p = 0.002] were predictive factors for the composite end-point. CONCLUSIONS: Malnutrition according to GLIM criteria represents a significant predictive risk factor for composite end-point of mortality and risk of hospitalization in SSc patients.

Type 2 cytokines and scleroderma interstitial lung disease.

Interstitial lung disease (ILD) is a life-threatening complication of systemic sclerosis (SSc). Type 2 (Th2) cytokines play a pivotal role in airway disease. Study aim was to evaluate serum level of Th2 interleukin (IL) and chemokine in SSc-ILD. Serum levels of IL-4, IL-5, IL-11, IL-13, IL-21, IL-31 and CXCL-13 were measured by Bio-Plex Multiplex Immunoassays in 60 SSc patients and 20 healthy controls (HC). Pulmonary function tests with diffusion lung capacity for carbon monoxide (DLco) and high resolution computed tomography (HRCT) were performed in SSc patients. ILD is defined as fibrotic changes (ground glass, reticular and honeycombing), assessed by Computer-Aided Lung Informatics for Pathology Evaluation and Ratings (CALIPER) software, affecting at least 10% of the lungs. Serum levels of Th2 cytokines were higher in SSc patients than HC. A linear correlation was observed between ground glass and IL-13 (r = 0.342, p < 0.01), IL-21 (r = 0.345, p < 0.01), IL-31 (r = 0.473, p < 0.001), IL-4 (r = 0.863, p < 0.001), IL-5 (r = 0.249, p < 0.05) and peripheral blood eosinophils (r = 0.463, p < 0.001). We found a negative correlation between DLco and IL-4 (r = - 0.511, p < 0.001) and peripheral blood eosinophils (r = - 0.446, p < 0.001). In the logistic regression analysis, IL-4 is associated with DLco ≤ 60% of the predicted [OR 1.039 (CI 95%: 1.015-1.064), p < 0.001], whilst mRSS [OR 1.138 (CI 95%: 1.023-1.266), p < 0.05] and IL-4 [OR 1.017 (CI 95%: 1-1.034), p < 0.05] were associated with ILD. Th2 inflammation could play a key role in early phase of SSc-ILD.

Tricuspid Annular Plane Systolic Excursion/Systolic Pulmonary Artery Pressure Ratio and Cardiorenal Syndrome Type 2 in the Systemic Sclerosis EUSTAR Cohort.

OBJECTIVE: The aim of the study was to evaluate the association between the tricuspid annular plane systolic excursion (TAPSE)/systolic pulmonary artery pressure (sPAP) ratio and estimated glomerular filtration rate (eGFR) and their association with mortality in the European Scleroderma Trials and Research (EUSTAR) cohort. METHODS: Patients with systemic sclerosis (SSc) from the EUSTAR database with TAPSE, sPAP, and parameters required to calculate eGFR were included. Logistic regression and Cox regression analysis were performed to evaluate TAPSE/sPAP as a risk factor for chronic kidney disease (CKD) and overall survival. RESULTS: A total of 2,370 patients with SSc were included; 284 (12%) patients had CKD stage 3a-5. TAPSE/sPAP (odds ratio [OR] 0.479; 95% CI 0.310-0.743; P < 0.001), arterial hypertension (OR 3.118; 95% CI 2.173-4.475; P < 0.001), diastolic dysfunction (OR 1.670; 95% CI 1.148-2.428; P < 0.01), and N-terminal pro-B-type natriuretic peptide (OR 1.165; 95% CI 1.041-1.304; P < 0.01) were associated with CKD stage 3a-5. TAPSE/sPAP ≤0.32 mm/mm Hg (hazard ratio [HR] 3.589; 95% CI 2.236-5.761; P < 0.001), eGFR <60 mL/min per 1.73 m2 (HR 2.818; 95% CI 1.777-4.468; P < 0.001), and age (HR 1.782; 95% CI 1.348-2.356; P < 0.001) were the most significant predictive factors for all-cause mortality. A total of 276 patients with SSc had pulmonary hypertension (PH) confirmed by right heart catheterization, with 69 (25%) having CKD stage 3a-5. No difference was found in eGFR between patients with PH with reduced or normal cardiac index. CONCLUSION: Reduced TAPSE/sPAP ratio is independently associated with CKD. TAPSE/sPAP ratio ≤0.32 mm/mm Hg and eGFR <60 mL/min per 1.73 m2 are prognostic factors for all-cause mortality. In patients with SSc with PH, eGFR is independent by reduced cardiac output.

Serum kynurenic acid is lower in systemic sclerosis patients with microvascular damage of hands.

BACKGROUND: Endothelial dysfunction occurs early in systemic sclerosis (SSc), leading to tissue hypoxia, vasoconstriction and fibrosis. It has been demonstrated that endothelial cells (ECs) are able to produce kynurenic acid (KYNA) in response to vascular inflammation, due to its anti-inflammatory and anti-oxidants activity. In SSc patients, blood perfusion of hands, assessed by laser speckle contrast analysis (LASCA), correlated negatively with the extent of the nailfold microvascular damage, scored according to nailfold videocapillaroscopy (NVC) classification. Aim of this study was to evaluate the difference of serum KYNA in SSc patients with different stages of microvascular damage. METHODS: Serum KYNA was assessed in 40 SSc patients at the enrolment. NVC was performed to evaluate capillaroscopic patterns (early, active and late). LASCA was performed to evaluate mean peripheral blood perfusion (PBP) of both hands and to evaluate the proximal-distal gradient (PDG). RESULTS: Median PDG was significantly lower in SSc patients with late NVC pattern compared to SSc patients with early and active NVC pattern [3.79 pU (IQR -8.55-18.16) vs 23.55 pU (IQR 14.92-43.80), p < 0.01]. Serum KYNA was significantly lower in SSc patients with late NVC pattern compared to SSc patient with early and active NVC pattern [45.19 ng/mL (IQR 42.70-54.74) vs 52.65 ng/mL (IQR 49.99-60.29), p < 0.05]. Moreover, SSc patients without PDG had significantly lower serum KYNA than in SSc patients with PDG [48.03 ng/mL (IQR 43.87-53.68) vs 59.27 ng/mL (IQR 49.15-71.00), p < 0.05]. CONCLUSION: KYNA is lower in SSc patients with late NCV pattern and without PDG. KYNA may be associated with early endothelial dysfunction.

The role of TAPSE/sPAP ratio in predicting pulmonary hypertension and mortality in the systemic sclerosis EUSTAR cohort.

OBJECTIVES: The study aim was to evaluate the predictive role of the echocardiography-derived tricuspid annular plane systolic excursion/systolic pulmonary artery pressure (TAPSE/sPAP) ratio for pulmonary hypertension (PH) diagnosis and mortality in the European Scleroderma Trials and Research (EUSTAR) cohort. METHODS: Eligible patients were systemic sclerosis (SSc) patients registered in the EUSTAR database with at least one visit recording TAPSE and sPAP data. Individual centres were required to provide TAPSE and sPAP data at 12 ± 3 months before right heart catheterization (RHC). Logistic regression analysis was applied to analyse the predictive ability of TAPSE/sPAP ratio for PH diagnosis. Cox regression analysis was performed to evaluate TAPSE/sPAP ratio as a predictive factor for all-cause mortality. RESULTS: 2555 SSc patients met the inclusion criteria for this study with 355 SSc patients having available RHC data at baseline. PH was confirmed by RHC in 195 SSc patients (54.9%). TAPSE/sPAP ratio < 0.55 mm/mmHg [OR 0.251 (95% CI 0.084-0.753), p < 0.05] and FVC/DLCO [OR 2.568 (95% CI 1.227-5.375), p < 0.05] were significantly associated with PH diagnosis. In logistic regression analysis with echocardiographic parameters at 12 ± 3 months before RHC, TAPSE/sPAP ratio < 0.55 mm/mmHg [OR 0.265 (95% CI 0.102-0.685), p < 0.01] and FVC/DLCO [OR 2.529 (95% CI 1.358-4.711), p < 0.01] were associated with PH diagnosis. In multivariate Cox regression analysis, TAPSE/sPAP ratio ≤ 0.32 mm/mmHg [HR 0.310 (0.164-0.585), p < 0.001] was the most significant predictive factor for death. CONCLUSIONS: TAPSE/sPAP ratio < 0.55 mm/mmHg is a predictive risk factor for PH. TAPSE/sPAP ratio ≤ 0.32 mm/mmHg is a predictive risk marker for all-cause mortality.

Serum Immunoglobulin G (IgG) Subclasses in a Cohort of Systemic Sclerosis Patients.

OBJECTIVES: To assess serum immunoglobulin G (IgG) subclasses in a cohort of systemic sclerosis (SSc) patients and to evaluate the influence of IgG subclasses in the main complications of the disease. METHODS: The serum level of IgG subclasses was evaluated in 67 SSc patients and 48 healthy controls (HC), matched for sex and age. Serum samples were collected and measured IgG1-4 subclasses by turbidimetry. RESULTS: SSc patients had lower median total IgG [9.88 g/l (IQR 8.18-11.42 g/l) vs. 12.09 g/l (IQR 10.24-13.54 g/l), p < 0.001], IgG1 [5.09 g/l (IQR 4.25-6.38 g/l) vs. 6.03 g/l (IQR 5.39-7.90 g/l), p < 0.001], and IgG3 [0.59 g/l (IQR 0.40-0.77 g/l) vs. 0.80 g/l (IQR 0.46-1 g/l), p < 0.05] serum levels compared to HC. The logistic regression analysis showed IgG3 as the only variable associated with the diffusing capacity of the lung for carbon monoxide (DLco) ≤60% of the predicted [OR 9.734 (CI 95%: 1.312-72.221), p < 0.05] and modified Rodnan skin score (mRSS) [OR 1.124 (CI 95%: 1.019-1.240), p < 0.05], anti-topoisomerase I [OR 0.060 (CI 95%: 0.007-0.535), p < 0.05], and IgG3 [OR 14.062 (CI 95%: 1.352-146.229), p < 0.05] as variables associated with radiological interstitial lung disease (ILD). CONCLUSION: SSc patients have reduced levels of total IgG and an altered IgG subclass distribution compared to HC. Moreover, SSc patients show different serum IgG subclasses profiles according to the main involvement of the disease.

In systemic sclerosis TAPSE/sPAP ratio is correlated with ventilatory efficiency and exercise capacity assessed by CPET.

OBJECTIVES: The aim of the study was to evaluate the correlation between cardiopulmonary exercise testing (CPET) parameters and right ventricular echocardiographic parameters for pulmonary arterial hypertension screening in a cohort of systemic sclerosis (SSc) patients. Methods forty SSc patients were examined using CPET and resting transthoracic echocardiography. CPET parameters analyzed were minute ventilation/carbon dioxide production (VE/VCO2) slope and maximum oxygen uptake (VO2 max); echocardiographic parameters were systolic pulmonary artery pressure (sPAP), tricuspid annular plane systolic excursion (TAPSE), and TAPSE/sPAP ratio. Results a positive correlation was observed between VE/VCO2 slope and age (r = 0.415, p < 0.01) and sPAP (r = 0.461, p < 0.01), conversely, a negative correlation was found between VE/VCO2 slope and TASPE/sPAP ratio (r = - 0.521, p = 0.001). VO2 max showed an inverse correlation with age (r = - 0.367, p < 0.05) and sPAP (r = - 0.387, p < 0.05) and a positive correlation with TAPSE/sPAP ratio (r = 0.521, p < 0.01). On stepwise linear regression analysis, VE/VCO2 slope was significantly correlated with TAPSE/sPAP ratio (ß coefficient = - 0.570; p < 0.0001), as well as VO2 max was significantly correlated with TAPSE/sPAP ratio (ß coefficient = 0.518; p = 0.001). Conclusion in SSc patients, TAPSE/sPAP ratio is the echocardiographic parameter of RV function which showed the best correlation with ventilatory efficiency and exercise capacity.

Role of kinurenic acid in the systemic sclerosis renal involvement.

Systemic sclerosis (SSc) subclinical renal vasculopathy is characterized by progressive increase of intrarenal stiffness and reduction of parenchymal thickness due to post ischemic fibrosis secondary to the renal Raynaud phenomenon. Aims of this study were to evaluate kinurenic acid (KYNA) serum level in SSc patients and healthy controls (HC) and to assess the role of KYNA in SSc subclinical nephropathy. Serum level of KYNA was evaluated in 52 SSc patients and 20 HC, matched for sex and age. Renal function was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation to estimate glomerular filtration rate (eGFR) and renal doppler ultrasound was performed to evaluate kidneys' morphology and indices of intrarenal stiffness. The parameters registered were renal longitudinal length, atrophy index (AI), renal sinus, parenchymal thickness, renal resistive index (RRI), pulsatile index (PI) and systolic/diastolic ratio (S/D). SSc patients had lower median value of KYNA than HC [54.43 ng/ml (IQR 44.44-63.64) vs 61.94 ng/ml (IQR 55.23-88.75), p < 0.001]. SSc patients with AI ≥ 0.70 had lower KYNA than SSc patients with AI < 0.70 [47.85 ng/ml (IQR 41.16-59.91) vs 55.5 ng/ml (IQR 49.99-67.33), p < 0.05] and a slightly significant negative linear correlation was found between KYNA and AI (r = - 0.249, p < 0.05). SSc patient with RRI ≥ 0.70 had higher KYNA than SSc patients with RRI < 0.70 [58.25 ng/ml (IQR 50.49-69.68) vs 50.07 ng/ml (IQR 42.70-56.31), p < 0.05] and a significant positive correlation was found between KYNA and RRI (r = 0.318, p < 0.05). KYNA may be used as a marker to evaluate the renal involvement in SSc patients.

Phase angle, nutritional status, and mortality in systemic sclerosis: An exploratory pilot study.

OBJECTIVES: Systemic sclerosis (SSc) is a rare autoimmune disease characterized by microvascular damage and fibrosis of the skin and internal organs. Among SSc complications, changes in nutritional status have a negative effect on quality of life and predispose patients to malnutrition. The aim of this exploratory pilot study was to examine whether bioelectrical impedance analysis-derived phase angle (PhA) is a parameter of nutritional status and a marker of mortality in patients with SSc. METHODS: Consecutive adult patients with SSc were included in the study. Biochemical analyses, anthropometric data, and bioelectrical impedance analysis assessments were recorded at the time of enrollment. The Malnutrition Universal Screening Tool (MUST) and Global Leadership Initiative on Malnutrition (GLIM) were applied to assess nutritional status. RESULTS: A total of 104 patients with SSc (88 women; median age: 55 y [interquartile range (IQR), 45.5- 66 y]) were enrolled. In patients with SSc and high malnutrition risk according to MUST, mean values of PhA were significantly lower than those of patients with SSc and low malnutrition risk (4° [IQR, 3.7°-4.4°] vs 4.6° [IQR, 4.2°-5.1°]; P = 0.004). Patients with SSc and malnutrition according to the GLIM criteria showed significantly lower PhA than patients with SSc but without malnutrition (3.8° [IQR, 3.5°-4.3°] vs 4.6° [IQR, 4.2°-5.1°]; P < 0.0001). Kaplan-Meier curves demonstrated that overall survival was significantly shorter (34.57 mo [±13.35] vs 48 mo [±0]; P = 0.001) in patients with SSc and PhA <3.75°. In the multivariate analysis, only PhA was a predictive factor for death (hazard ratio: 0.283; 95% confidence interval, 0.083-0.965; P = 0.044). CONCLUSIONS: The data obtained suggest that lower PhA values in patients with SSc are associated with an increased malnutrition risk with MUST, malnutrition with GLIM, and increased mortality. Additional studies are necessary to confirm these preliminary results.

Serum-soluble ST2 and systemic sclerosis arthropathy.

Interleukin (IL)33 and its receptor ST2 have been involved in the pathogenesis of several conditions, including arthritis. The aim of the study was to evaluate the association between IL33 or soluble ST2 (sST2) serum levels and systemic sclerosis (SSc) articular involvement. IL33 and sST2 serum levels were measured in 64 SSc patients and 24 HC matched for sex and age. Articular involvement assessed by using Disease Activity Score 28 based on erythrocyte sedimentation rate (DAS28-ESR), presence of tendon friction rubs (TFRs) and finger-to-palm (FTP) distance. sST2 serum levels were significantly higher in SSc patients with DAS28-ESR > 3.2 than in SSc patients with DAS28-ESR⩽3.2 [9726.1 (IQR 7746.5 - 14,953.5) pg/mL vs 7611.7 (IQR 5162.6 -11,036.7) pg/mL; p < 0.05]. sST2 serum levels were significantly higher in SSc patients with TFRs compared to SSc patients without TFRs [9726.1 (IQR 7746.5 - 14,953.5) pg/mL vs 7426.4 (IQR 5145.9 - 10,593.5) pg/mL; p < 0.01] and in SSc patients with FTP ≥ 1 cm compared to SSc patients with FTP < 1 cm [9683.7 (IQR 8067.2 - 16,387.6) pg/mL vs 7679.1 (IQR 5246.1 - 11,472.2) pg/mL; p < 0.05]. No significant association was observed between IL33 and DAS28-ESR, TFRs and FTP. A slightly positive linear correlation was found between sST2 and Disease Activity Index (r = 0.294, p < 0.05) and Disease Severity Scale (r = 0.265, p < 0.05). sST2 serum levels were positively correlated with DAS28-ESR (r = 0.371, p < 0.01). Elevated sST2 serum levels were associated with higher articular disease activity, TFRs and hand dysfunction, suggesting that sST2 might have a role in the pathogenesis of SSc articular involvement. Key Points • In SSc patients elevated serum levels of sST2 were associated with higher articular disease activity • High serum levels of sST2 were reported in SSc patients with TFRs and hand dysfunction • sST2 might have a role in the pathogenesis of SSc articular involvement.

Interleukin-33 and soluble suppression of tumorigenicity 2 in scleroderma cardiac involvement.

Interleukin (IL)-33 is part of the IL-1 family of cytokines and soluble suppression of tumorigenicity 2 (sST2) is part of the family of IL-1 receptors. In systemic sclerosis (SSc), IL-33 and sST2 are involved in cardiac manifestations such as diastolic dysfunction (DD), autonomic dysfunction (AD) and right ventricular-pulmonary arterial coupling assessed by tricuspid annular plane systolic excursion (TAPSE)/systolic pulmonary artery pressure (sPAP). Serum levels of IL33 and sST2 were assessed in 50 SSc patients and 14 healthy controls (HC). Clinical assessment, echocardiography and heart rate variability (HRV) analysis were performed in SSc patients. Serum levels of IL-33 and sST2 were significantly higher in SSc patients than HC. A linear positive correlation between modified Rodnan skin score and IL33 was observed. Serum values of sST2 were higher in SSc patients with DD than in patients without DD [15403 pg/ml (12,208-19,941) vs 8556 pg/ml (6820-11,036), p < 0.001]. sST2 showed a negative correlation with standard deviation of normal-to-normal RR intervals (SDNN) (r = - 0.281, p < 0.05) and positive correlation with low frequency/high frequency (LF/HF) (r = 0,349, p < 0.01). Negative linear correlation exists between sST2 and TAPSE/sPAP (r = - 0.398, p < 0.01). Serum levels of IL-33 and sST2 are higher in SSc patients than HC. Serum levels of sST2 are a potential marker of DD, AD and right ventricular-pulmonary arterial coupling.

Serum Adiponectin, a Novel Biomarker Correlates with Skin Thickness in Systemic Sclerosis.

The aim was to evaluate the longitudinal association between basal serum adiponectin and repeated measurements of skin thickness during 12 months of follow-up in systemic sclerosis (SSc) patients. We enrolled SSc patients with disease duration > 2 years in a prospective observational study. Skin thickness was measured at baseline and after 12 months of follow-up with modified Rodnan skin score (mRSS). Baseline serum adiponectin was determined using a commercial ELISA kit. We enrolled 66 female SSc patients (median age 54 years, IQR 42−62 years). The median disease duration was 12 (IQR 8−16) years and median baseline serum adiponectin was 9.8 (IQR 5.6−15.6) mcg/mL. The median mRSS was 10 (IQR 6−18) at baseline and 12 (IQR 7−18) at follow-up. A significant correlation was observed between baseline serum adiponectin and disease duration (r = 0.264, p < 0.05), age (r = 0.515, p < 0.0001), baseline mRSS (r = −0.303, p < 0.05), and mRSS at follow-up (r = −0.322, p < 0.001). In multiple regression analysis, only mRSS at follow-up showed an inverse correlation with baseline serum adiponectin (ß = −0.132, p < 0.01). The reduction in serum adiponectin levels is correlated with skin thickness.

The Effect of SARS-CoV-2 Vaccination on B-Cell Phenotype in Systemic Sclerosis Patients.

OBJECTIVE: to assess the influence of SARS-CoV-2 mRNA vaccine on B-cell phenotypes in systemic sclerosis (SSc). METHODS: peripheral blood B-cell subpopulations were evaluated before (t1) and 3 months (t3) after the second dose of vaccine in 28 SSc patients. Peripheral blood B-cell subpopulations were evaluated in 21 healthy controls (HCs) only at t1. Anti-spike IgG levels were evaluated at t3 in both cohorts. RESULTS: SSc patients presented higher naive, double-negative, and CD21low B cells compared to HCs. IgM-memory and switched-memory B cells were lower in SSc patients than HCs. No differences in anti-spike IgG levels after vaccination were observed between SSc patients and HCs. Anti-spike IgG levels after vaccination were lower in SSc patients with increased CD21low B cells at baseline compared to SSc patients with normal CD21low B cells. A positive correlation was found between IgG levels and naive B cells. A negative linear correlation was shown between IgG levels and IgM-memory, switched-memory, double-negative, and CD21low B cells. CONCLUSIONS: SARS-CoV-2 mRNA vaccine response is normal in SSc patients not undergoing immunosuppressive therapy. The normal number of naive B cells is a positive marker of antibody response. The increased percentage of CD21low B cells represents a negative marker of antibody response.

Antibody response to BNT162b2 SARS-CoV-2 mRNA vaccine in adult patients with systemic sclerosis.

OBJECTIVES: Systemic sclerosis (SSc) patients are at risk for a severe disease course during SARS-CoV-2 infection either due to comorbidities or immunosuppression. The availability of SARS-CoV-2 vaccines is crucial for the prevention of this hard-to-treat illness. The aim of this study is to assess the humoral response after mRNA vaccination against SARS-CoV-2 in SSc patients. METHOD: Seropositivity rate and serum IgG levels were evaluated 1 month (t1) and 3 months (t3) after the second dose of vaccine in a cohort of SSc patients and healthy controls (HC). Differences were made with Student's or Mann-Whitney's t-test and with the chi-square or Fisher exact test. Logistic regression model including immunosuppressive treatments (corticosteroids, CCS; mycophenolate mofetil, MMF; methotrexate, MTX; rituximab, RTX) was built to assess the predictivity for seropositivity. RESULTS: The seropositivity rate was similar in 78 SSc patients compared to 35 HC at t1 but lower at t3. SSc patients had lower serum IgG levels than HC at t1 but not at t3. SSc patients treated with immunosuppressive therapy showed both a lower seropositive rate (t1, 90.3% vs 100%; t3, 87.1% vs 97.9%; p < 0.05) and serum IgG levels than untreated patients both at t1 [851 BAU/ml (IQR 294-1950) vs 1930 BAU/ml (IQR 1420-3020); p < 0.001] and t3 [266 BAU/ml (IQR 91.7-597) vs 706 BAU/ml (IQR 455-1330); p < 0.001]. In logistic regression analysis, only MTX was significant [OR 39.912 (95% CI 1.772-898.728); p < 0.05]. CONCLUSIONS: SSc patients treated with MTX had a lower serological response to mRNA vaccine, and even low doses of CCS can adversely affect antibody titer and vaccination response. Key Points • SSc patients are able to produce vaccine-induced antibodies after mRNA vaccination. • In SSc patients, clinical characteristics of disease did not influence seropositivity rate. • In SSc patients, even low doses of CCS can adversely affect antibody titer and vaccination response. • In SSc patients, MTX treatment is mainly associated with reduced seropositivity and lower serum IgG levels.

Maresin1 is a predictive marker of new digital ulcers in systemic sclerosis patients.

BACKGROUND: Digital ulcers (DUs) are one of the main causes of disability among systemic sclerosis (SSc) patients. The inflammation plays a crucial role in mediating the pathophysiological process underlying SSc. Objective of this study was to evaluate Maresin1 (MaR1) serum levels in SSc patients and in healthy controls (HC). Secondary aims were to evaluate the relationship between MaR and diseases variables and to assess the predictive role of MaR1 in the development of new digital ulcers (DUs) during 18 weeks follow-up. METHODS: MaR1 serum level was evaluated in 55 SSc patients and 24 HC. In SSc patients, clinical assessment was performed at baseline and after 18 week follow-up by the same-blinded observer on serum MaR1 levels. RESULTS: MaR1 was significantly lower in SSc patients than in HC [367 pg/ml (IQR 304-468.3 pg/ml) vs 467.7 pg/ml (IQR 422-522 pg/ml), p < 0.001]. During follow-up, six patients (10.9%) developed DUs. MaR1 was higher in SSc patients with new DUs than in patients without new DUs [518.2 pg/ml (IQR 468.2-596.5 pg/ml) vs 355 pg/ml (IQR 299.8-444.7 pg/ml), p < 0.01]. Free survival from new DUs is significantly lower in SSc patients with increased MaR1 serum level than in SSc patient with normal MaR1 serum level. In multivariate analysis, serum level of MaR1 > 393.2 pg/ml is a predictive marker for new DUs. CONCLUSION: In SSc patients, MaR1 is reduced compared to HC and it is a predictive marker of new DUs.

Increased Complement Activation in Systemic Sclerosis Patients with Skin and Lung Fibrosis.

INTRODUCTION: The involvement of complement system in the phenotypic expression of systemic sclerosis (SSc) is a debated topic. We aimed to assay complement fractions in SSc patients and to correlate their levels with the clinical course of disease. KEY POINTS: 1. CH50 is increased in SSc patients compared to HC; 2. Serum C2 levels are increased in SSc patients compared to HC; 3. CH50 may represent a biomarker of skin and lung fibrosis severity in SSc patients. METHOD: Complement hemolysis 50% (CH50), C2, C3 and C4 levels have been assessed in 85 SSc patients and 47 healthy controls (HC). RESULTS: SSc patients displayed a statistically significant higher value of CH50 [76.3 U/mL (IQR 65.8-89.4 U/mL) vs. 29.6 U/mL (IQR 24.7-34 U/mL); p < 0.0001] and of C2 [26.1 mg/L (IQR 24.1-32.1 mg/L) vs. 22.7 mg/L (IQR 20.6-24.4 mg/L); p < 0.0001] if compared to HC. Patients with diffuse cutaneous SSc (dcSSc) had higher levels of CH50 than patients with limited cutaneous SSc (lcSSc) [83.6 U/mL (IQR 72.3-102.7 U/mL) vs. 71.3 U/mL (IQR 63.7-83.6 U/mL); p = 0.003]. SSc patients with interstitial lung disease (ILD) had higher CH50 levels if compared to SSc patients without ILD [79.6 U/mL (IQR 68.3-97.4 U/mL) vs. 69.7 U/mL (54.6-85.7 U/mL); p = 0.042]. A positive linear correlation existed between CH50 and the modified Rodnan Skin Score (mRSS) (r = 0.285, p = 0.008) and disease severity scale (DSS) (r = 0.285, p = 0.005); a negative linear correlation was demonstrated between CH50 and the diffusing capacity of carbon monoxide (DLco) (r = -0.252, p = 0.012). In multiple linear regression analysis, only DSS was significant (p = 0.01, beta coefficient 2.446). CONCLUSIONS: Our results show an increment of CH50 and serum C2 levels in SSc patients in comparison to HC; we retain that CH50 may represent a biomarker of disease severity and of skin and lung fibrosis in these patients.

In systemic sclerosis, the TAPSE/sPAP ratio can be used in addition to the DETECT algorithm for pulmonary arterial hypertension diagnosis.

OBJECTIVE: Early detection of pulmonary arterial hypertension (PAH) is crucial for improving patient outcomes. The aim of this study was to compare the positive predictive value (PPV) of the echocardiography-derived tricuspid annular plane systolic excursion/systolic pulmonary artery pressure (TAPSE/sPAP) ratio with that of the DETECT algorithm for PAH screening in a cohort of SSc patients. METHODS: Fifty-one SSc patients were screened for PAH using the DETECT algorithm and echocardiography. RESULTS: Echocardiography was recommended by the DETECT algorithm step 1 in 34 patients (66.7%). Right heart catheterization (RHC) was recommended by the DETECT algorithm step 2 in 16 patients (31.4%). PAH was confirmed by RHC in 5 patients. The DETECT algorithm PPV was 31.3%. The TAPSE/sPAP ratio was higher in SSc patients not referred for RHC than in SSc patients referred for RHC according to the DETECT algorithm step 2 [0.83 (0.35-1.40) mm/mmHg vs 0.74 (0.12-1.09) mm/mmHg, P < 0.05]. Using a cut-off of 0.60 mm/mmHg, 8 (15.7%) SSc patients had a TAPSE/sPAP ratio of ≤0.60 mm/mmHg. PAH was confirmed by RHC in 5 patients. The PPV of TAPSE/sPAP was 62.5%. In multiple regression analysis, TAPSE/sPAP was associated with age [ß coefficient = -0.348 (95% CI: -0.011, -0.003); P < 0.01], DETECT algorithm step 1 [ß coefficient = 1.023 (95% CI: 0.006, 0.024); P < 0.01] and DETECT algorithm step 2 (ß coefficient = -1.758 [95% CI: -0.059, -0.021]; P < 0.0001). CONCLUSION: In SSc patients with a DETECT algorithm step 2 total score of >35, the TAPSE/sPAP ratio can be used to further select patients requiring RHC to confirm PAH diagnosis.