Polyarticular JIA (polyarticular + jia)

Distribution by Scientific Domains


Selected Abstracts


Juvenile idiopathic arthritis profile in Turkish children

PEDIATRICS INTERNATIONAL, Issue 2 2008
Mustafa Yilmaz
Abstract Background: Juvenile idiopathic arthritis (JIA) is a heterogeneous group of disorders. Publications from different countries point to differences in the disease manifestation of JIA among different populations. The aim of the present paper was to evaluate the clinical and laboratory features of JIA in Turkish children. Methods: A total of 196 JIA patients who fulfilled International League of Associations for Rheumatology (ILAR) diagnostic criteria were included in this retrospective study. The data collected were age, gender, age at disease onset and at diagnosis, and follow-up duration. Antinuclear antibody (ANA), rheumatoid factor (RF), and human leukocyte antigen B-27 were evaluated for each patient. Results: There were 102 boys and 94 girls with a mean duration of disease of 4.1 years. The mean age at the first visit was 8.8 years, and the mean age at onset of disease was 6.8 years (range, 8 months,15 years). Polyarticular JIA was the most frequent onset type (37.2%). Other subtypes included oligoarthritis (34.2%), systemic arthritis (15.3%), psoriatic arthritis (1%), enthesitis-related arthritis (9.7%), and other arthritis (2.2%). ANA was positive in 28 patients (14.2%). Chronic uveitis occurred in two patients with oligoarthritis; and two patients with enthesitis-related arthritis had acute uveitis. Three patients (1.4%) developed amyloidosis. Conclusion: Compared to reports from Western countries, remarkably different features of JIA were found in Turkish children, which included higher frequency of polyarticular JIA, higher prevalence among boys, lower rate of ANA positivity and uveitis. Further studies are required to understand how genetic and environmental differences affect JIA expression. [source]


Juvenile idiopathic arthritis and HLA Class I and Class II interactions and age-at-onset effects

ARTHRITIS & RHEUMATISM, Issue 6 2010
Jill A. Hollenbach
Objective The aim of this study was to quantitate risk and to examine heterogeneity for HLA at high resolution in patients with the most common subtypes of juvenile idiopathic arthritis (JIA), IgM rheumatoid factor,negative polyarticular JIA and oligoarticular JIA. Use of 4-digit comprehensive HLA typing enabled great precision, and a large cohort allowed for consideration of both age at disease onset and disease subtype. Methods Polymerase chain reaction,based high-resolution HLA typing for class I and class II loci was accomplished for 820 patients with JIA and 273 control subjects. Specific HLA epitopes, potential interactions of alleles at specific loci and between loci (accounting for linkage disequilibrium and haplotypic associations), and an assessment of the current International League of Associations for Rheumatology classification criteria were considered. Results An HLA,DRB1/DQB1 effect was shown to be exclusively attributable to DRB1 and was similar between patients with oligoarticular JIA and a younger subgroup of patients with polyarticular JIA. Furthermore, patients with polyarticular JIA showed age-specific related effects, with disease susceptibility in the group older than age 6 years limited to an effect of the HLA,DRB1*08 haplotype, which is markedly different from the additional susceptibility haplotypes, HLA,DRB1*1103/1104, found in the group with oligoarticular JIA and the group of younger patients with polyarticular JIA. Also in contrast to findings for oligoarticular JIA, patients with polyarticular arthritis had no evidence of an HLA class I effect. Markers associated with a reduced risk of disease included DRB1*1501, DRB1*0401, and DRB1*0701. DRB1*1501 was shown to reduce risk across the whole cohort, whereas DRB1*0401 and DRB1*0701 were protective for selected JIA subtypes. Surprisingly, the disease predisposition mediated by DPB1*0201 in individuals without any disease-predisposing DRB1 alleles was great enough to overcome even the very strong protective effect observed for DRB1*1501. Conclusion Inherited HLA factors in JIA show similarities overall as well as differences between JIA subtypes. [source]


Synovial fluid proteins differentiate between the subtypes of juvenile idiopathic arthritis

ARTHRITIS & RHEUMATISM, Issue 6 2010
Margalit E. Rosenkranz
Objective Juvenile idiopathic arthritis (JIA) is a heterogeneous group of inflammatory diseases, and no clinically useful prognostic markers to predict disease outcome in children with JIA are currently available. Synovial fluid likely reflects the proteins present in the inflamed synovium. The purpose of this study was to delineate the synovial fluid proteome and determine whether protein expression differs in the different subtypes of JIA. Methods Synovial fluid samples obtained from children with oligoarticular JIA, polyarticular JIA, or systemic JIA were compared. Two-dimensional gel electrophoresis for protein separation and matrix-assisted laser desorption ionization,time-of-flight mass spectrometry and quadripole time-of-flight mass spectrometry for protein identification were used for this study. Synovial fluid cells were analyzed by polymerase chain reaction (PCR) for the presence of haptoglobin messenger RNA (mRNA). Results The synovial fluid proteome of the samples was delineated. The majority of proteins showed overexpression in JIA synovial fluid as compared with noninflammatory control samples. There were 24 statistically significantly differentially expressed spots (>2-fold change; P < 0.05) between the subtypes of JIA. PCR analysis revealed haptoglobin mRNA, suggesting that haptoglobin is locally produced in an inflamed joint in JIA. Conclusion Despite the similar histologic appearance of inflamed joints in patients with different subtypes of JIA, there are differences in protein expression according to the subtype of JIA. Haptoglobin is differentially expressed between the subtypes of JIA and is locally produced in an inflamed joint in JIA. Haptoglobin and other differentially expressed proteins may be potential biomarkers in JIA. [source]


Defective phosphorylation of interleukin-18 receptor , causes impaired natural killer cell function in systemic-onset juvenile idiopathic arthritis

ARTHRITIS & RHEUMATISM, Issue 9 2009
Wilco de Jager
Objective Systemic-onset juvenile idiopathic arthritis (JIA) is an autoimmune disease characterized by arthritis and systemic features. Its pathogenesis is still largely unknown. It is characterized immunologically by natural killer (NK) cell dysfunction and cytokine signatures that predominantly feature interleukin-1 (IL-1), IL-6, and IL-18. Since IL-18 can drive NK cell function, we examined how the high plasma levels of this cytokine are related to the documented NK cell failure in these patients. Methods The phenotype and function of NK cells from 10 healthy control subjects, 15 patients with polyarticular JIA, and 15 patients with systemic-onset JIA were characterized by staining and functional assays in vitro. IL-18 ligand binding was visualized by fluorescence microscopy. Phosphorylation of several MAP kinases and the IL-18 receptor , (IL-18R,) were visualized by Western blotting. Results IL-18 from the plasma of systemic-onset JIA patients stimulated the activation of NK cells from healthy controls and bound its cognate receptor. However, NK cells from systemic-onset JIA patients failed to up-regulate cell-mediated killing molecules, such as perforin and interferon-,, after IL-18 stimulation. Furthermore, treatment with IL-18 did not induce the phosphorylation of receptor-activated MAP kinases in NK cells. Alternate activation of NK cells by IL-12 induced NK cell cytotoxicity. We observed no additive effect of IL-18 in combination with IL-12 in systemic-onset JIA patients. Immunoprecipitation of IL-18R, showed that NK cells from systemic-onset JIA could not phosphorylate this receptor after IL-18 stimulation. Conclusion The mechanism of the impaired NK cell function in systemic-onset JIA involves a defect in IL-18R, phosphorylation. This observation has major implications for the understanding and, ultimately, the treatment of systemic-onset JIA. [source]


Gene expression signatures in polyarticular juvenile idiopathic arthritis demonstrate disease heterogeneity and offer a molecular classification of disease subsets

ARTHRITIS & RHEUMATISM, Issue 7 2009
Thomas A. Griffin
Objective To determine whether peripheral blood mononuclear cells (PBMCs) from children with recent-onset polyarticular juvenile idiopathic arthritis (JIA) exhibit biologically or clinically informative gene expression signatures. Methods Peripheral blood samples were obtained from 59 healthy children and 61 children with polyarticular JIA prior to treatment with second-line medications, such as methotrexate or biologic agents. RNA was extracted from isolated mononuclear cells, fluorescence labeled, and hybridized to commercial gene expression microarrays (Affymetrix HG-U133 Plus 2.0). Data were analyzed using analysis of variance at a 5% false discovery rate threshold after robust multichip analysis preprocessing and distance-weighted discrimination normalization. Results Initial analysis revealed 873 probe sets for genes that were differentially expressed between polyarticular JIA patients and healthy controls. Hierarchical clustering of these probe sets distinguished 3 subgroups within the polyarticular JIA group. Prototypical patients within each subgroup were identified and used to define subgroup-specific gene expression signatures. One of these signatures was associated with monocyte markers, another with transforming growth factor ,,inducible genes, and a third with immediate early genes. Correlation of gene expression signatures with clinical and biologic features of JIA subgroups suggested relevance to aspects of disease activity and supported the division of polyarticular JIA into distinct subsets. Conclusion Gene expression signatures in PBMCs from patients with recent-onset polyarticular JIA reflect discrete disease processes and offer a molecular classification of disease. [source]


Variants in TNFAIP3, STAT4, and C12orf30 loci associated with multiple autoimmune diseases are also associated with juvenile idiopathic arthritis

ARTHRITIS & RHEUMATISM, Issue 7 2009
Sampath Prahalad
Objective Subtypes of juvenile idiopathic arthritis (JIA) share phenotypic features with other autoimmune disorders. We investigated several genetic variants associated with rheumatoid arthritis (RA) and other autoimmune disorders for association with JIA to test the hypothesis that clinically distinct phenotypes share common genetic susceptibility factors. Methods Cases were 445 children with JIA, and controls were 643 healthy adults. Using the TaqMan assay, subjects were genotyped for 8 single-nucleotide polymorphisms in 7 loci including rs10499194 and rs6920220 in the TNFAIP3 locus, rs6679677 in the RSBN1 locus, rs17696736 in the C12orf30 locus, rs3761847 in the TRAF1/C5 locus, rs2104286 in the IL2RA locus, rs7574865 in the STAT4 locus, and rs2542151 in the PTPN2 locus. Alleles and genotypes were analyzed for association with JIA and JIA subtypes. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. Results The strongest associations with JIA risk or protection were observed for TNFAIP3 variants rs10499194 (OR 0.74 [95% CI 0.61,0.91], P < 0.004) and rs6920220 (OR 1.30 [95% CI 1.05,1.61], P = 0.015). We also observed associations between JIA and both STAT4 (OR 1.24 [95% CI 1.02,1.51], P = 0.029) and C12orf30 (OR 1.20 [95% CI 1.01,1.43], P = 0.041) variants. The PTPN2 variant rs2542151 deviated from Hardy-Weinberg equilibrium and was excluded from analyses. Variants in IL2RA, TRAF1/C5, and RSBN1 were not associated with JIA. After stratification by JIA subtype, the TNFAIP3 and C12orf30 variants were associated with oligoarticular JIA, while the STAT4 variant was associated primarily with polyarticular JIA. Conclusion We have demonstrated associations between JIA and variants in the TNFAIP3, STAT4, and C12orf30 regions that have previously shown associations with other autoimmune diseases, including RA and systemic lupus erythematosus. Our results suggest that clinically distinct autoimmune phenotypes share common genetic susceptibility factors. [source]


Gene expression profiling in neutrophils from children with polyarticular juvenile idiopathic arthritis

ARTHRITIS & RHEUMATISM, Issue 5 2009
James N. Jarvis
Objective We have previously reported a defect in neutrophil activation in children with polyarticular juvenile idiopathic arthritis (JIA). The current study was undertaken to determine whether gene expression abnormalities persist in JIA in remission and to use systems biology analysis to elucidate pathologic pathways in polyarticular JIA. Methods We performed gene expression profiling on neutrophils from children with polyarticular JIA. Children were grouped according to disease status. We studied 14 children with active disease who were taking medication, 8 children with clinical remission of disease who were taking medication (CRM status), and 6 children with clinical remission of disease who were not taking medication (CR status). We also studied 13 healthy children whose age ranges overlapped those of the patients. Results Neutrophil abnormalities persisted in children with polyarticular JIA even after disease remission was achieved. Children with active disease and those with CRM status showed no differences in expression of specific genes, although they could be separated on cluster analysis. A comparison of children with CR status and healthy control children revealed networks of pro- and antiinflammatory genes that suggested that remission is a state of homeostasis and balance rather than a return to normal immune function. Furthermore, gene overexpression in patients with CR status supports the hypothesis that neutrophils play a role in regulating adaptive immunity in this disease. Conclusion Neutrophil gene profiling in polyarticular JIA suggests important roles for neutrophils in disease pathogenesis. These findings suggest the presence of complex interactions between innate and adaptive immunity, that are not easily modeled in conventional, linear, reductionist systems. [source]


Radiologic features in juvenile idiopathic arthritis: A first step in the development of a standardized assessment method

ARTHRITIS & RHEUMATISM, Issue 2 2003
Marion A. J. Van Rossum
Objective To describe radiologic features of patients with juvenile idiopathic arthritis (JIA) in a standardized manner, to test the reliability and feasibility of this description, and to correlate these features with clinical signs as a first step in the development of a standardized assessment method. Methods The placebo-controlled study of sulfasalazine in patients with oligoarticular, extended oligoarticular, and polyarticular JIA performed by the Dutch Juvenile Idiopathic Arthritis Study Group yielded the data for this study. All trial entry radiographs (clinically involved joints and contralateral joints) were scored (in consensus by a skeletal radiologist and pediatric rheumatologist) for the presence of swelling, osteopenia, joint space narrowing, growth abnormalities, subchondral bone cysts, erosions, and malalignment. Results Data on 67 of 69 patients were analyzed. The mean age was 9.1 years (range 2.5,17.6 years), and the median disease duration was 24 months (range 5,176 months). Thirteen percent of the patients were IgM rheumatoid factor (IgM-RF) positive, and 16% were HLA,B27 positive. All 68 clinically evaluated joints were included in the maximum of 19 radiographed joints (or joint groups) per patient. The mean number of radiographed joints per patient was 7 (range 2,15); knees, hands, ankles, and feet were most frequently affected. Fifty-eight patients (87%) had radiologic abnormalities in at least one joint (soft-tissue swelling in 63% of patients, growth disturbances in 48%, joint space narrowing in 28%, and erosions in 15%). In total, half of the radiographs of the clinically involved joints showed radiologic abnormalities, including two-thirds of the radiographs of the clinically affected hands and knees. Univariate analysis revealed a good correlation between the overall articular (clinical) severity and the presence of radiologic abnormalities (odds ratio [OR] 1.38, P < 0.0001). Multivariate analysis showed increased ORs for the presence of radiologic abnormalities and IgM-RF positivity (OR 4.6, P = 0.005) or HLA,B27 positivity (OR 3.0, P = 0.004). In general, reproducibility of the radiologic scoring method was good (mean kappa coefficient of 0.74 [range 0.40,0.86]), although there were scoring discrepancies for swelling, osteopenia, and growth disturbances. The scoring took 10,20 minutes per patient. Conclusion Our model of describing and scoring radiologic abnormalities of radiographed joints in JIA was feasible, mostly reproducible, correlated well with the overall articular severity score, and added substantial new information not available on clinical examination. [source]