Objective: To validate and refine two sets of candidate criteria for the classification/diagnosis of axial spondyloarthritis (SpA). Methods: All Assessment of SpondyloArthritis international Society (ASAS) members were invited to include consecutively new patients with chronic (>3 months) back pain of unknown origin that began before 45 years of age. The candidate criteria were first tested in the entire cohort of 649 patients from 25 centres, and then refined in a random selection of 40% of cases and thereafter validated in the remaining 60%. Results: Upon diagnostic work-up, axial SpA was diagnosed in 60.2% of the cohort. Of these, 70% did not fulfil modified New York criteria and, therefore, were classified as having ''non-radiographic'' axial SpA. Refinement of the candidate criteria resulted in new ASAS classification criteria that are defined as: the presence of sacroiliitis by radiography or by magnetic resonance imaging (MRI) plus at least one SpA feature (''imaging arm'') or the presence of HLA-B27 plus at least two SpA features (''clinical arm''). The sensitivity and specificity of the entire set of the new criteria were 82.9% and 84.4%, and for the imaging arm alone 66.2% and 97.3%, respectively. The specificity of the new criteria was much better than that of the European Spondylarthropathy Study Group criteria modified for MRI (sensitivity 85.1%, specificity 65.1%) and slightly better than that of the modified Amor criteria (sensitivity 82.9, specificity 77.5%). Conclusion:The new ASAS classification criteria for axial SpA can reliably classify patients for clinical studies and may help rheumatologists in clinical practice in diagnosing axial SpA in those with chronic back pain. Trial registration number: NCT00328068.

Objective To evaluate new classifi cation criteria for peripheral spondyloarthritis (SpA) in patients with SpA with peripheral manifestations only. Methods In this Assessment of SpondyloArthritis international Society (ASAS) study, two prespecifi ed sets of criteria were compared against the European Spondylarthropathy Study Group (ESSG) and Amor criteria in newly referred consecutive patients with undiagnosed peripheral arthritis, and/or enthesitis, and/ or dactylitis that usually began before 45 years of age. The clinical diagnosis (SpA vs no SpA) made by the ASAS rheumatologist served as reference standard. Results In all, 24 ASAS centres included 266 patients, with a fi nal diagnosis of SpA being made in 66.2%. After adjustments a fi nal set of criteria showed the best balance between sensitivity (77.8%) and specifi city (82.9%): arthritis and/or enthesitis and/or dactylitis plus (A) one or more of the following parameters: psoriasis, infl ammatory bowel disease, preceding infection, human leucocyte antigen B27, uveitis, sacroiliitis on imaging, or (B) two or more other parameters: arthritis, enthesitis, dactylitis, infl ammatory back pain in the past, family history of SpA. The new criteria performed better than modifi ed versions of the ESSG (sensitivity 62.5%, specifi city 81.1%) and the Amor criteria (sensitivity 39.8%, specifi city 97.8%), particularly regarding sensitivity. In the entire ASAS population of 975 patients the combined use of ASAS criteria for axial SpA and ASAS criteria for peripheral SpA also had a better balance (sensitivity 79.5%, specifi city 83.3%) than the modifi ed ESSG (sensitivity 79.1%, specifi city 68.8%) and Amor criteria (sensitivity 67.5%, specifi city 86.7%), respectively. Conclusions The new ASAS classifi cation criteria for peripheral SpA performed well in patients presenting with peripheral arthritis, enthesitis and/or dactylitis.

No abstract

Takayasu arteritis is a rare inflammatory disease of large arteries. The etiology of Takayasu arteritis remains poorly understood, but genetic contribution to the disease pathogenesis is supported by the genetic association with HLA-B*52. We genotyped ~200,000 genetic variants in two ethnically divergent Takayasu arteritis cohorts from Turkey and North America by using a custom-designed genotyping platform (Immunochip). Additional genetic variants and the classical HLA alleles were imputed and analyzed. We identified and confirmed two independent susceptibility loci within the HLA region (r(2) < 0.2): HLA-B/MICA (rs12524487, OR = 3.29, p = 5.57 × 10(-16)) and HLA-DQB1/HLA-DRB1 (rs113452171, OR = 2.34, p = 3.74 × 10(-9); and rs189754752, OR = 2.47, p = 4.22 × 10(-9)). In addition, we identified and confirmed a genetic association between Takayasu arteritis and the FCGR2A/FCGR3A locus on chromosome 1 (rs10919543, OR = 1.81, p = 5.89 × 10(-12)). The risk allele in this locus results in increased mRNA expression of FCGR2A. We also established the genetic association between IL12B and Takayasu arteritis (rs56167332, OR = 1.54, p = 2.18 × 10(-8)).

The aim of this study was to develop a Turkish version of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and assess its reliability, validity, and sensitivity to change. The Turkish version was obtained after a translation and back-translation process. Seventy-one patients with ankylosing spondylitis were assessed with it. To assess its validity, patients were also evaluated with the Turkish version of the Bath Ankylosing Spondylitis Functional Index (BASFI), the Bath Ankylosing Spondylitis Metrology Index (BASMI), the Bath Ankylosing Spondylitis Patient Global Score (BAS-G), and physicians' assessments of disease activity. Over 24 h, the Turkish BASDAI did not show significant differences between the two assessments (P>0.05). Correlations were found between BASDAI and all of the evaluation parameters except BASMI (P<0.01). Both BASDAI and BASMI showed significant improvements after 8-week home exercise programmes. The results of this study show that the Turkish version of the BASDAI is reliable, valid, and sensitive to change.