Application and performance of disease activity indices proposed for patients with systemic sclerosis in an international cohort of patients with juvenile systemic sclerosis.

Objectives: Juvenile systemic sclerosis is a rare childhood disease. Three disease activity indices have been published for adult patients with systemic sclerosis: the European Scleroderma Study Group Index, a modified version of the European Scleroderma Study Group Index and the revised European Scleroderma Trials and Research index. The objective of this study was to determine the feasibility and performance of the three disease activity indices in a prospectively followed cohort of patients with juvenile systemic sclerosis. Methods: The analysis cohort was selected from the prospective international inception cohort enrolling juvenile systemic sclerosis patients. The correlation of the disease activity indices with the physicians' and the patients' global assessment of disease activity was determined. The disease activity indices were compared between patients with active and inactive disease. Sensitivity to change between 6- and 12-month follow-up was investigated by mixed models. Results: Eighty percent of the 70 patients had a diffuse cutaneous subtype. The revised European Scleroderma Trials and Research index was highly correlated with the physician-reported global disease activity/parents-reported global disease activity (r = 0.74/0.64), followed by the European Scleroderma Study Group activity index (r = 0.61/0.55) and the modified version of the European Scleroderma Study Group activity index (r = 0.51/0.43). The disease activity indices significantly differed between active and inactive patients. The disease activity indices showed sensitivity to change between 6- and 12-month follow-up among patients who improved or worsened according to the physician-reported global disease activity and the parents-reported global disease activity. Conclusion: Overall, no disease activity score is superior to the other, and all three scores have limitations in the application in juvenile systemic sclerosis patients. Furthermore, research on the concept of disease activity and suitable scores to measure disease activity in patients with juvenile systemic sclerosis is necessary in future.

Gender differences in juvenile systemic sclerosis patients: Results from the international juvenile scleroderma inception cohort.

Objective: To compare organ involvement and disease severity between male and female patients with juvenile onset systemic sclerosis. Methods: Demographics, organ involvement, laboratory evaluation, patient-reported outcomes and physician assessment variables were compared between male and female juvenile onset systemic sclerosis patients enrolled in the prospective international juvenile systemic sclerosis cohort at their baseline visit and after 12 months. Results: One hundred and seventy-five juvenile onset systemic sclerosis patients were evaluated, 142 females and 33 males. Race, age of onset, disease duration, and disease subtypes (70% diffuse cutaneous) were similar between males and females. Active digital ulceration, very low body mass index, and tendon friction rubs were significantly more frequent in males. Physician global assessment of disease severity and digital ulcer activity was significantly higher in males. Composite pulmonary involvement was also more frequent in males, though not statistically significantly. After 12 months, they are the pattern of differences changed female patients had significantly more frequent pulmonary involvement. Conclusion: In this cohort, juvenile onset systemic sclerosis had a more severe course in males at baseline and but the pattern changed after 12 months. Some differences from adult findings persisted, there is no increased signal of pulmonary arterial hypertension or heart failure in male pediatric patients. While monitoring protocols of organ involvement in juvenile onset systemic sclerosis need to be identical for males and females.

Underdetection of Interstitial Lung Disease in Juvenile Systemic Sclerosis.

OBJECTIVE: Utilizing data obtained from a prospective, international, juvenile systemic sclerosis (SSc) cohort, the present study was undertaken to determine if pulmonary screening with forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLco) is sufficient to assess the presence of interstitial lung disease (ILD) in comparison to high-resolution computed tomography (HRCT) in juvenile SSc. METHODS: The juvenile SSc cohort database was queried for patients enrolled from January 2008 to January 2020 with recorded pulmonary function tests (PFTs) parameters and HRCT to determine the discriminatory properties of PFT parameters, FVC, and DLco in detecting ILD. RESULTS: Eighty-six juvenile SSc patients had both computed tomography imaging and FVC values for direct comparison. Using findings on HRCT as the standard measure of ILD presence, the sensitivity of FVC in detecting ILD in juvenile SSc was only 40%, the specificity was 77%, and area under the curve (AUC) was 0.58. Fifty-eight juvenile SSc patients had both CT imaging and DLco values for comparison. The sensitivity of DLco in detecting ILD was 76%, the specificity was 70%, and AUC was 0.73. CONCLUSION: The performance of PFTs in juvenile SSc to detect underlying ILD was quite limited. Specifically, the FVC, which is one of the main clinical parameters in adult SSc to detect and monitor ILD, would miss ~60% of children who had ILD changes on their accompanying HRCT. The DLco was more sensitive in detecting potential abnormalities on HRCT, but with less specificity than the FVC. These results support the use of HRCT in tandem with PFTs for the screening of ILD in juvenile SSc.

Differences Sustained Between Diffuse and Limited Forms of Juvenile Systemic Sclerosis in an Expanded International Cohort.

OBJECTIVE: To evaluate the baseline clinical characteristics of juvenile systemic sclerosis (SSc) patients in the international juvenile SSc inception cohort, and to compare these characteristics between the classically defined juvenile diffuse cutaneous SSc (dcSSc) and limited cutaneous SSc (lcSSc) subtypes and among those with overlap features. METHODS: A cross-sectional study was performed using baseline visit data. Information on demographic characteristics, organ system evaluation, treatment, and patient- and physician-reported outcomes was extracted and summary statistics applied. Comparisons between juvenile dcSSc and lcSSc subtypes and patients with and without overlap features were performed using chi-square and Mann-Whitney U tests. RESULTS: At data extraction, 150 juvenile SSc patients were enrolled across 42 centers; 83% were White, 80% were female, juvenile dcSSc predominated (72%), and 17% of the cohort had overlap features. Significant differences were found between juvenile dcSSc and juvenile lcSSc regarding modified Rodnan skin thickness score, the presence of Gottron's papules, digital tip ulceration, results of the 6-minute walk test, and composite pulmonary and cardiac involvement. All of these were more frequent in dcSSc except for cardiac involvement. Juvenile dcSSc patients had significantly worse scores for physician-rated disease activity and damage. A significantly higher occurrence of Gottron's papules and musculoskeletal and composite pulmonary involvement, and a significantly lower frequency of Raynaud's phenomenon, were seen in those with overlap features. CONCLUSION: Results from a large international juvenile SSc cohort demonstrate significant differences between juvenile dcSSc and juvenile lcSSc patients, including more globally severe disease and increased frequency of interstitial lung disease in juvenile dcSSc patients, while those with lcSSc have more frequent cardiac involvement. Those with overlap features had an unexpected higher frequency of interstitial lung disease.

Are diffuse and limited juvenile systemic sclerosis different in clinical presentation? Clinical characteristics of a juvenile systemic sclerosis cohort.

Introduction: Juvenile systemic sclerosis is an orphan disease. Currently, the majority of juvenile systemic sclerosis cohort studies are retrospective in design without standardized assessment. This study was conducted prospectively to investigate the difference in manifestations of limited cutaneous juvenile systemic sclerosis and diffuse cutaneous juvenile systemic sclerosis subtypes. An additional aim was to compare these data to other juvenile systemic sclerosis cohorts and a large adult systemic sclerosis cohort. Methods: Patients fulfilling the Paediatric Rheumatology European Society juvenile systemic sclerosis classification criteria were included. Clinical characteristics and patient-related outcomes were assessed. Results: In all, 88 patients with a mean disease duration of 3.5 years were enrolled, 72.5% with diffuse cutaneous juvenile systemic sclerosis with a mean modified Rodnan Skin score of 18 and 27.5% with limited cutaneous juvenile systemic sclerosis with mean modified Rodnan Skin score of 9. The mean age at the onset of Raynaud's and first non-Raynaud's symptoms was similar in both groups, approximately 9 and 10.5 years. Active digital tip ulcerations were present in 29% diffuse cutaneous juvenile systemic sclerosis and none in the limited cutaneous juvenile systemic sclerosis subjects (p = 0.005). Of those with cardiopulmonary testing, 3% of diffuse cutaneous juvenile systemic sclerosis and 23% of limited cutaneous juvenile systemic sclerosis group had cardiac involvement (p = 0.015), and 41% diffuse cutaneous juvenile systemic sclerosis and 22% of the limited cutaneous juvenile systemic sclerosis group had pulmonary involvement (p = 0.009). Physician global disease damage assessment was higher in the diffuse cutaneous juvenile systemic sclerosis group compared to the limited cutaneous juvenile systemic sclerosis group: 35 and 15 (p = 0.021). Discussion: The majority of this international juvenile systemic sclerosis cohort had diffuse cutaneous juvenile systemic sclerosis (72.5%) with more frequent vascular and pulmonary involvement compared to the limited cutaneous group, who had increased cardiac involvement. Our cohort reflects prior findings of published juvenile systemic sclerosis cohorts and emphasizes a difference in the presentation compared to adult-onset systemic sclerosis.