Clonally expanding smooth muscle cells promote atherosclerosis by escaping efferocytosis and activating the complement cascade.

Atherosclerosis is the process underlying heart attack and stroke. Despite decades of research, its pathogenesis remains unclear. Dogma suggests that atherosclerotic plaques expand primarily via the accumulation of cholesterol and inflammatory cells. However, recent evidence suggests that a substantial portion of the plaque may arise from a subset of "dedifferentiated" vascular smooth muscle cells (SMCs) which proliferate in a clonal fashion. Herein we use multicolor lineage-tracing models to confirm that the mature SMC can give rise to a hyperproliferative cell which appears to promote inflammation via elaboration of complement-dependent anaphylatoxins. Despite being extensively opsonized with prophagocytic complement fragments, we find that this cell also escapes immune surveillance by neighboring macrophages, thereby exacerbating its relative survival advantage. Mechanistic studies indicate this phenomenon results from a generalized opsonin-sensing defect acquired by macrophages during polarization. This defect coincides with the noncanonical up-regulation of so-called don't eat me molecules on inflamed phagocytes, which reduces their capacity for programmed cell removal (PrCR). Knockdown or knockout of the key antiphagocytic molecule CD47 restores the ability of macrophages to sense and clear opsonized targets in vitro, allowing for potent and targeted suppression of clonal SMC expansion in the plaque in vivo. Because integrated clinical and genomic analyses indicate that similar pathways are active in humans with cardiovascular disease, these studies suggest that the clonally expanding SMC may represent a translational target for treating atherosclerosis.

18F-Fluorodeoxyglucose-Positron Emission Tomography Imaging Detects Response to Therapeutic Intervention and Plaque Vulnerability in a Murine Model of Advanced Atherosclerotic Disease-Brief Report.

OBJECTIVE: This study sought to determine whether 18F-fluorodeoxyglucose-positron emission tomography/computed tomography could be applied to a murine model of advanced atherosclerotic plaque vulnerability to detect response to therapeutic intervention and changes in lesion stability. Approach and Results: To analyze plaques susceptible to rupture, we fed ApoE-/- mice a high-fat diet and induced vulnerable lesions by cast placement over the carotid artery. After 9 weeks of treatment with orthogonal therapeutic agents (including lipid-lowering and proefferocytic therapies), we assessed vascular inflammation and several features of plaque vulnerability by 18F-fluorodeoxyglucose-positron emission tomography/computed tomography and histopathology, respectively. We observed that 18F-fluorodeoxyglucose-positron emission tomography/computed tomography had the capacity to resolve histopathologically proven changes in plaque stability after treatment. Moreover, mean target-to-background ratios correlated with multiple characteristics of lesion instability, including the corrected vulnerability index. CONCLUSIONS: These results suggest that the application of noninvasive 18F-fluorodeoxyglucose-positron emission tomography/computed tomography to a murine model can allow for the identification of vulnerable atherosclerotic plaques and their response to therapeutic intervention. This approach may prove useful as a drug discovery and prioritization method.

Secondary analysis of APPLE study suggests atorvastatin may reduce atherosclerosis progression in pubertal lupus patients with higher C reactive protein.

OBJECTIVE: Participants in the Atherosclerosis Prevention in Paediatric Lupus Erythematosus (APPLE) trial were randomised to placebo or atorvastatin for 36 months. The primary endpoint, reduced carotid intima medial thickness (CIMT) progression, was not met but atorvastatin-treated participants showed a trend of slower CIMT progression. Post-hoc analyses were performed to assess subgroup benefit from atorvastatin therapy. METHODS: Subgroups were prespecified and defined by age (> or ≤15.5 years), systemic lupus erythematosus (SLE) duration (> or ≤24 months), pubertal status (Tanner score≥4 as post-pubertal or <4 as pre-pubertal), low density lipoprotein cholesterol (LDL) (≥ or <110 mg/dl) and high-sensitivity C reactive protein (hsCRP) (≥ or <1.5 mg/l). A combined subgroup (post-pubertal and hsCRP≥1.5 mg/l) was compared to all others. Longitudinal linear mixed-effects models were developed using 12 CIMT and other secondary APPLE outcomes (lipids, hsCRP, disease activity and damage, and quality of life). Three way interaction effects were assessed for models. RESULTS: Significant interaction effects with trends of less CIMT progression in atorvastatin-treated participants were observed in pubertal (3 CIMT segments), high hsCRP (2 CIMT segments), and the combined high hsCRP and pubertal group (5 CIMT segments). No significant treatment effect trends were observed across subgroups defined by age, SLE duration, LDL for CIMT or other outcome measures. CONCLUSIONS: Pubertal status and higher hsCRP were linked to lower CIMT progression in atorvastatin-treated subjects, with most consistent decreases in CIMT progression in the combined pubertal and high hsCRP group. While secondary analyses must be interpreted cautiously, results suggest further research is needed to determine whether pubertal lupus patients with high CRP benefit from statin therapy. TRIAL REGISTRATION: Clinical Trials.gov Identifier: NCT00065806.

The pleiotropic benefits of statins include the ability to reduce CD47 and amplify the effect of pro-efferocytic therapies in atherosclerosis.

The pleiotropic benefits of statins may result from their impact on vascular inflammation. The molecular process underlying this phenomenon is not fully elucidated. Here, RNA sequencing designed to investigate gene expression patterns following CD47-SIRPα inhibition identifies a link between statins, efferocytosis, and vascular inflammation. In vivo and in vitro studies provide evidence that statins augment programmed cell removal by inhibiting the nuclear translocation of NFκB1 p50 and suppressing the expression of the critical 'don't eat me' molecule, CD47. Statins amplify the phagocytic capacity of macrophages, and thus the anti-atherosclerotic effects of CD47-SIRPα blockade, in an additive manner. Analyses of clinical biobank specimens suggest a similar link between statins and CD47 expression in humans, highlighting the potential translational implications. Taken together, our findings identify efferocytosis and CD47 as pivotal mediators of statin pleiotropy. In turn, statins amplify the anti-atherosclerotic effects of pro-phagocytic therapies independently of any lipid-lowering effect.

Unsupervised Learning for Automated Detection of Coronary Artery Disease Subgroups.

Background The promise of precision population health includes the ability to use robust patient data to tailor prevention and care to specific groups. Advanced analytics may allow for automated detection of clinically informative subgroups that account for clinical, genetic, and environmental variability. This study sought to evaluate whether unsupervised machine learning approaches could interpret heterogeneous and missing clinical data to discover clinically important coronary artery disease subgroups. Methods and Results The Genetic Determinants of Peripheral Arterial Disease study is a prospective cohort that includes individuals with newly diagnosed and/or symptomatic coronary artery disease. We applied generalized low rank modeling and K-means cluster analysis using 155 phenotypic and genetic variables from 1329 participants. Cox proportional hazard models were used to examine associations between clusters and major adverse cardiovascular and cerebrovascular events and all-cause mortality. We then compared performance of risk stratification based on clusters and the American College of Cardiology/American Heart Association pooled cohort equations. Unsupervised analysis identified 4 phenotypically and prognostically distinct clusters. All-cause mortality was highest in cluster 1 (oldest/most comorbid; 26%), whereas major adverse cardiovascular and cerebrovascular event rates were highest in cluster 2 (youngest/multiethnic; 41%). Cluster 4 (middle-aged/healthiest behaviors) experienced more incident major adverse cardiovascular and cerebrovascular events (30%) than cluster 3 (middle-aged/lowest medication adherence; 23%), despite apparently similar risk factor and lifestyle profiles. In comparison with the pooled cohort equations, cluster membership was more informative for risk assessment of myocardial infarction, stroke, and mortality. Conclusions Unsupervised clustering identified 4 unique coronary artery disease subgroups with distinct clinical trajectories. Flexible unsupervised machine learning algorithms offer the ability to meaningfully process heterogeneous patient data and provide sharper insights into disease characterization and risk assessment. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT00380185.

Chitinase 3 like 1 is a regulator of smooth muscle cell physiology and atherosclerotic lesion stability.

AIMS: Atherosclerotic cerebrovascular disease underlies the majority of ischaemic strokes and is a major cause of death and disability. While plaque burden is a predictor of adverse outcomes, plaque vulnerability is increasingly recognized as a driver of lesion rupture and risk for clinical events. Defining the molecular regulators of carotid instability could inform the development of new biomarkers and/or translational targets for at-risk individuals. METHODS AND RESULTS: Using two independent human endarterectomy biobanks, we found that the understudied glycoprotein, chitinase 3 like 1 (CHI3L1), is up-regulated in patients with carotid disease compared to healthy controls. Further, CHI3L1 levels were found to stratify individuals based on symptomatology and histopathological evidence of an unstable fibrous cap. Gain- and loss-of-function studies in cultured human carotid artery smooth muscle cells (SMCs) showed that CHI3L1 prevents a number of maladaptive changes in that cell type, including phenotype switching towards a synthetic and hyperproliferative state. Using two murine models of carotid remodelling and lesion vulnerability, we found that knockdown of Chil1 resulted in larger neointimal lesions comprised by de-differentiated SMCs that failed to invest within and stabilize the fibrous cap. Exploratory mechanistic studies identified alterations in potential downstream regulatory genes, including large tumour suppressor kinase 2 (LATS2), which mediates macrophage marker and inflammatory cytokine expression on SMCs, and may explain how CHI3L1 modulates cellular plasticity. CONCLUSION: CHI3L1 is up-regulated in humans with carotid artery disease and appears to be a strong mediator of plaque vulnerability. Mechanistic studies suggest this change may be a context-dependent adaptive response meant to maintain vascular SMCs in a differentiated state and to prevent rupture of the fibrous cap. Part of this effect may be mediated through downstream suppression of LATS2. Future studies should determine how these changes occur at the molecular level, and whether this gene can be targeted as a novel translational therapy for subjects at risk of stroke.

Serum S100A8/A9 and S100A12 Levels in Children With Polyarticular Forms of Juvenile Idiopathic Arthritis: Relationship to Maintenance of Clinically Inactive Disease During Anti-Tumor Necrosis Factor Therapy and Occurrence of Disease Flare After Discontinuation of Therapy.

OBJECTIVE: To determine the relationship between serum levels of S100A8/A9 and S100A12 and the maintenance of clinically inactive disease during anti-tumor necrosis factor (anti-TNF) therapy and the occurrence of disease flare following withdrawal of anti-TNF therapy in patients with polyarticular forms of juvenile idiopathic arthritis (JIA). METHODS: In this prospective, multicenter study, 137 patients with polyarticular-course JIA whose disease was clinically inactive while receiving anti-TNF therapy were enrolled. Patients were observed for an initial 6-month phase during which anti-TNF treatment was continued. For those patients who maintained clinically inactive disease over the 6 months, anti-TNF was withdrawn and they were followed up for 8 months to assess for the occurrence of flare. Serum S100 levels were measured at baseline and at the time of anti-TNF withdrawal. Spearman's rank correlation test, Mann-Whitney U test, Kruskal-Wallis test, receiver operating characteristic (ROC) curve, and Kaplan-Meier survival analyses were used to assess the relationship between serum S100 levels and maintenance of clinically inactive disease and occurrence of disease flare after anti-TNF withdrawal. RESULTS: Over the 6-month initial phase with anti-TNF therapy, the disease state reverted from clinically inactive to clinically active in 24 (18%) of the 130 evaluable patients with polyarticular-course JIA; following anti-TNF withdrawal, 39 (37%) of the 106 evaluable patients experienced a flare. Serum levels of S100A8/A9 and S100A12 were elevated in up to 45% of patients. Results of the ROC analysis revealed that serum S100 levels did not predict maintenance of clinically inactive disease during anti-TNF therapy nor did they predict disease flare after treatment withdrawal. Elevated levels of S100A8/A9 were not predictive of the occurrence of a disease flare within 30 days, 60 days, 90 days, or 8 months following anti-TNF withdrawal, and elevated S100A12 levels had a modest predictive ability for determining the risk of flare within 30, 60, and 90 days after treatment withdrawal. Serum S100A12 levels at the time of anti-TNF withdrawal were inversely correlated with the time to disease flare (r = -0.36). CONCLUSION: Serum S100 levels did not predict maintenance of clinically inactive disease or occurrence of disease flare in patients with polyarticular-course JIA, and S100A12 levels were only moderately, and inversely, correlated with the time to disease flare.

Assessing the performance of the Birmingham Vasculitis Activity Score at diagnosis for children with antineutrophil cytoplasmic antibody-associated vasculitis in A Registry for Childhood Vasculitis (ARChiVe).

OBJECTIVE: There are no validated tools for measuring disease activity in pediatric vasculitis. The Birmingham Vasculitis Activity Score (BVAS) is a valid disease activity tool in adult vasculitis. Version 3 (BVAS v.3) correlates well with physician's global assessment (PGA), treatment decision, and C-reactive protein in adults. The utility of BVAS v.3 in pediatric vasculitis is not known. We assessed the association of BVAS v.3 scores with PGA, treatment decision, and erythrocyte sedimentation rate (ESR) at diagnosis in pediatric antineutrophil cytoplasmic antibody-associated vasculitis (AAV). METHODS: Children with AAV diagnosed between 2004 and 2010 at all ARChiVe centers were eligible. BVAS v.3 scores were calculated with a standardized online tool (www.vasculitis.org). Spearman's rank correlation coefficient (r(s)) was used to test the strength of association between BVAS v.3 and PGA, treatment decision, and ESR. RESULTS: A total of 152 patients were included. The physician diagnosis of these patients was predominantly granulomatosis with polyangiitis (n = 99). The median BVAS v.3 score was 18.0 (range 0-40). The BVAS v.3 correlations were r(s) = 0.379 (95% CI 0.233 to 0.509) with PGA, r(s) = 0.521 (95% CI 0.393 to 0.629) with treatment decision, and r(s) = 0.403 (95% CI 0.253 to 0.533) with ESR. CONCLUSION: Applied to children with AAV, BVAS v.3 had a weak correlation with PGA and moderate correlation with both ESR and treatment decision. Prospective evaluation of BVAS v.3 and/or pediatric-specific modifications to BVAS v.3 may be required before it can be formalized as a disease activity assessment tool in pediatric AAV.

Increased sensitivity of the European medicines agency algorithm for classification of childhood granulomatosis with polyangiitis.

OBJECTIVE: Granulomatosis with polyangiitis (Wegener's; GPA) and other antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are rare in childhood and are sometimes difficult to discriminate. We compared use of adult-derived classification schemes for GPA against validated pediatric criteria in the ARChiVe (A Registry for Childhood Vasculitis e-entry) cohort, a Childhood Arthritis and Rheumatology Research Alliance initiative. METHODS: Time-of-diagnosis data for children with physician (MD) diagnosis of AAV and unclassified vasculitis (UCV) from 33 US/Canadian centers were analyzed. The European Medicines Agency (EMA) classification algorithm and European League Against Rheumatism/Paediatric Rheumatology International Trials Organisation/Paediatric Rheumatology European Society (EULAR/PRINTO/PRES) and American College of Rheumatology (ACR) criteria for GPA were applied to all patients. Sensitivity and specificity were calculated (MD-diagnosis as reference). RESULTS: MD-diagnoses for 155 children were 100 GPA, 25 microscopic polyangiitis (MPA), 6 ANCA-positive pauciimmune glomerulonephritis, 3 Churg-Strauss syndrome, and 21 UCV. Of these, 114 had GPA as defined by EMA, 98 by EULAR/PRINTO/PRES, and 87 by ACR. Fourteen patients were identified as GPA by EULAR/PRINTO/PRES but not by ACR; 3 were identified as GPA by ACR but not EULAR/PRINTO/PRES. Using the EMA algorithm, 135 (87%) children were classifiable. The sensitivity of the EMA algorithm, the EULAR/PRINTO/PRES, and ACR criteria for classifying GPA was 90%, 77%, and 69%, respectively, with specificities of 56%, 62%, and 67%. The relatively poor sensitivity of the 2 criteria related to their inability to discriminate patients with MPA. CONCLUSION: EULAR/PRINTO/PRES was more sensitive than ACR criteria in classifying pediatric GPA. Neither classification system has criteria for MPA; therefore usefulness in discriminating patients in ARChiVe was limited. Even when using the most sensitive EMA algorithm, many children remained unclassified.

Do adult disease severity subclassifications predict use of cyclophosphamide in children with ANCA-associated vasculitis? An analysis of ARChiVe study treatment decisions.

OBJECTIVE: To determine whether adult disease severity subclassification systems for antineutrophil cytoplasmic antibody-associated vasculitis (AAV) are concordant with the decision to treat pediatric patients with cyclophosphamide (CYC). METHODS: We applied the European Vasculitis Study (EUVAS) and Wegener's Granulomatosis Etanercept Trial (WGET) disease severity subclassification systems to pediatric patients with AAV in A Registry for Childhood Vasculitis (ARChiVe). Modifications were made to the EUVAS and WGET systems to enable their application to this cohort of children. Treatment was categorized into 2 groups, "cyclophosphamide" and "no cyclophosphamide." Pearson's chi-square and Kendall's rank correlation coefficient statistical analyses were used to determine the relationship between disease severity subgroup and treatment at the time of diagnosis. RESULTS: In total, 125 children with AAV were studied. Severity subgroup was associated with treatment group in both the EUVAS (chi-square 45.14, p < 0.001, Kendall's tau-b 0.601, p < 0.001) and WGET (chi-square 59.33, p < 0.001, Kendall's tau-b 0.689, p < 0.001) systems; however, 7 children classified by both systems as having less severe disease received CYC, and 6 children classified as having severe disease by both systems did not receive CYC. CONCLUSION: In this pediatric AAV cohort, the EUVAS and WGET adult severity subclassification systems had strong correlation with physician choice of treatment. However, a proportion of patients received treatment that was not concordant with their assigned severity subclass.

Toward the development of criteria for global flares in juvenile systemic lupus erythematosus.

OBJECTIVE: To develop a definition of global flare in juvenile systemic lupus erythematosus (SLE) and derive candidate criteria for measuring juvenile SLE flares. METHODS: Pediatric rheumatologists answered 2 Delphi questionnaires to achieve consensus on a common definition of juvenile SLE flare and identify variables for use in candidate flare criteria. The diagnostic accuracy of these candidate flare criteria was tested with data from juvenile SLE patients (n = 98; 623 visits total). Physician-rated change in the juvenile SLE course (worsening, yes/no) between visits served as the criterion standard. RESULTS: There was 96% consensus that a "a flare is a measurable worsening of juvenile SLE disease activity in at least one organ system, involving new or worse signs of disease that may be accompanied by new or worse SLE symptoms. Depending on the severity of the flare, more intensive therapy may be required." Variables suggested for use in flare criteria were: physician-rated disease activity (V1), patient well-being, protein:creatinine ratio, a validated disease activity index (V2), the Child Health Questionnaire physical summary score (V3), anti-double-stranded DNA antibodies, erythrocyte sedimentation rate, and complement levels. Using multiple logistic regression, several candidate flare criteria were derived with area under the receiver operating characteristic curve (AUC) as high as 0.92 (sensitivity >or=85%, specificity >or=85%); classification and regression tree analysis suggested that V1, V2, and V3 suffice to identify juvenile SLE flares (AUC 0.81; sensitivity = 64%, specificity = 86%). CONCLUSION: Consensus about a definition of global disease flare for juvenile SLE has been obtained and promising candidate flare criteria have been developed. These will need further assessment of their ease of use and accuracy in prospective study.

Abatacept improves health-related quality of life, pain, sleep quality, and daily participation in subjects with juvenile idiopathic arthritis.

OBJECTIVE: To assess health-related quality of life (HRQOL) in abatacept-treated children/adolescents with juvenile idiopathic arthritis (JIA). METHODS: In this phase III, double-blind, placebo-controlled trial, subjects with active polyarticular course JIA and an inadequate response/intolerance to ≥1 disease-modifying antirheumatic drug (including biologics) received abatacept 10 mg/kg plus methotrexate (MTX) during the 4-month open-label period (period A). Subjects achieving the American College of Rheumatology Pediatric 30 criteria for improvement (defined "responders") were randomized to abatacept or placebo (plus MTX) in the 6-month double-blind withdrawal period (period B). HRQOL assessments included 15 Child Health Questionnaire (CHQ) health concepts plus the physical (PhS) and psychosocial summary scores (PsS), pain (100-mm visual analog scale), the Children's Sleep Habits Questionnaire, and a daily activity participation questionnaire. RESULTS: A total of 190 subjects from period A and 122 from period B were eligible for analysis. In period A, there were substantial improvements across all of the CHQ domains (greatest improvement was in pain/discomfort) and the PhS (8.3 units) and PsS (4.3 units) with abatacept. At the end of period B, abatacept-treated subjects had greater improvements versus placebo in all domains (except behavior) and both summary scores. Similar improvement patterns were seen with pain and sleep. For participation in daily activities, an additional 2.6 school days/month and 2.3 parents' usual activity days/month were gained in period A responders with abatacept, and further gains were made in period B (1.9 versus 0.9 [P = 0.033] and 0.2 versus -1.3 [P = 0.109] school days/month and parents' usual activity days/month, respectively, in abatacept- versus placebo-treated subjects). CONCLUSION: Improvements in HRQOL were observed with abatacept, providing real-life tangible benefits to children with JIA and their parents/caregivers.

Premature atherosclerosis in pediatric systemic lupus erythematosus: risk factors for increased carotid intima-media thickness in the atherosclerosis prevention in pediatric lupus erythematosus cohort.

OBJECTIVE: To evaluate risk factors for subclinical atherosclerosis in a population of patients with pediatric systemic lupus erythematosus (SLE). METHODS: In a prospective multicenter study, a cohort of 221 patients underwent baseline measurements of carotid intima-media thickness (CIMT) as part of the Atherosclerosis Prevention in Pediatric Lupus Erythematosus (APPLE) trial. SLE disease measures, medications, and traditional risk factors for atherosclerosis were assessed. A standardized protocol was used to assess the thickness of the bilateral common carotid arteries and the mean maximal IMT of 12 segments. Univariable analysis identified potential associations with CIMT, which were examined in multivariable linear regression modeling. RESULTS: Based on the mean-mean common or the mean-max CIMT as the dependent variable, univariable analysis showed significant associations of the following variables with increased CIMT: increasing age, longer SLE duration, minority status, higher body mass index (BMI), male sex, increased creatinine clearance, higher lipoprotein(a) level, proteinuria, azathioprine treatment, and prednisone dose. In multivariable modeling, both azathioprine use (P=0.005 for the mean-mean model and P=0.102 for the mean-max model) and male sex (P<0.001) were associated with increases in the mean-max CIMT. A moderate dosage of prednisone (0.15-0.4 mg/kg/day) was associated with decreases in the mean-max CIMT (P=0.024), while high-dose and low-dose prednisone were associated with increases in the mean-mean common CIMT (P=0.021) and the mean-max CIMT (P=0.064), respectively. BMI (P<0.001) and creatinine clearance (P=0.031) remained associated with increased mean-mean common CIMT, while increasing age (P<0.001) and increasing lipoprotein(a) level (P=0.005) were associated with increased mean-max CIMT. CONCLUSION: Traditional as well as nontraditional risk factors were associated with increased CIMT in this cohort of patients in the APPLE trial. Azathioprine treatment was associated with increased CIMT. The relationship between CIMT and prednisone dose may not be linear.

Classification, presentation, and initial treatment of Wegener's granulomatosis in childhood.

OBJECTIVE: To compare the criteria for Wegener's granulomatosis (WG) of the American College of Rheumatology (ACR) with those of the European League Against Rheumatism/Pediatric Rheumatology European Society (EULAR/PRES) in a cohort of children with WG and other antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs), and to describe the interval to diagnosis, presenting features, and initial treatment for WG. METHODS: Eligible patients had been diagnosed by site rheumatologists (termed the "MD diagnosis") since 2004. This diagnosis was used as a reference standard for sensitivity and specificity testing of the 2 WG classification criteria. Descriptive analyses were confined to ACR-classified WG patients. RESULTS: MD diagnoses of 117 patients (82 of whom were female) were WG (n = 76), microscopic polyangiitis (n = 17), ANCA-positive pauci-immune glomerulonephritis (n = 5), Churg-Strauss syndrome (n = 2), and unclassified vasculitis (n = 17). The sensitivities of the ACR and EULAR/PRES classification criteria for WG among the spectrum of AAVs were 68.4% and 73.6%, respectively, and the specificities were 68.3% and 73.2%, respectively. Two more children were identified as having WG by the EULAR/PRES criteria than by the ACR criteria. For the 65 ACR-classified WG patients, the median age at diagnosis was 14.2 years (range 4-17 years), and the median interval from symptom onset to diagnosis was 2.7 months (range 0-49 months). The most frequent presenting features by organ system were constitutional (89.2%), pulmonary (80.0%), ear, nose, and throat (80.0%), and renal (75.4%). Fifty-four patients (83.1%) commenced treatment with the combination of corticosteroids and cyclophosphamide, with widely varying regimens; the remainder received methotrexate alone (n = 1), corticosteroids alone (n = 4), or a combination (n = 6). CONCLUSION: The EULAR/PRES criteria minimally improved diagnostic sensitivity and specificity for WG among a narrow spectrum of children with AAVs. Diagnostic delays may result from poor characterization of childhood WG. Initial therapy varied considerably among participating centers.

Systemic sclerosis in childhood: clinical and immunologic features of 153 patients in an international database.

OBJECTIVE: To determine the clinical and immunologic features of systemic sclerosis (SSc) in a large group of children and describe the clinical evolution of the disease and compare it with the adult form. METHODS: Data on 153 patients with juvenile SSc collected from 55 pediatric rheumatology centers in Europe, Asia, and South and North America were analyzed. Demographic, clinical, and immunologic characteristics of children with juvenile SSc at the onset, at diagnosis, and during the disease course were evaluated. RESULTS: Raynaud's phenomenon was the most frequent symptom, followed by skin induration in approximately 75% of patients. Musculoskeletal symptoms were present in one-third of patients, and the most frequently involved internal organs were respiratory and gastrointestinal, while involvement of renal, cerebral, and cardiovascular systems was extremely rare. Antinuclear antibodies were present in the sera of 81% of patients. Anti-topoisomerase I (Scl-70) and anticentromere antibodies were found to be positive in 34% and 7.1% of patients, respectively. Involvement of the respiratory, gastrointestinal, and cardiovascular systems was more frequent and occurred earlier in patients who died than in those who survived. Compared with the adult form, juvenile SSc appears to be less severe, with the involvement of fewer internal organs, particularly at the time of diagnosis, and has a less characterized immunologic profile. CONCLUSION: This study provides information on the largest collection of patients with juvenile SSc ever reported. Juvenile SSc appears to be less severe than in adults because children have less internal organ involvement, a less specific autoantibody profile, and a better long-term outcome.