Georgina Salvador

Validity, reproducibility, and responsiveness of a twelve‐joint simplified power doppler ultrasonographic assessment of joint inflammation in rheumatoid arthritis

OBJECTIVE To investigate the validity, reproducibility, and responsiveness of a simplified power Doppler ultrasound (PDUS) assessment of joint inflammation compared with a comprehensive 44-joint PDUS assessment in patients with rheumatoid arthritis (RA) who started therapy with a biologic agent. METHODS A total of 160 patients with active RA who started a biologic agent were prospectively recruited in 18 Spanish centers. The patients underwent clinical and laboratory assessment and blinded PDUS examination at baseline and 6 months. A PDUS examination of 128 synovial sites in 44 joints was performed. US synovitis and PD signal were semiquantitatively graded from 1 to 3 in all synovial sites. US count and index for synovitis and PD signal were obtained. PDUS intraobserver and interobserver reliability were evaluated. A process of data reduction based on the frequency of involvement of synovial sites by both synovitis and PD signal was conducted. Construct and discriminant validity of a simplified PDUS assessment was investigated. RESULTS A PDUS simplified assessment including 24 synovial sites from 12 joints detected 100% of patients with synovitis and 91% of patients with PD signal. There was a highly significant correlation between the 44-joint count and index for synovitis and PD signal and the 12-joint count and index for synovitis and PD signal at baseline and 6 months (r = 0.84-0.90, P < 0.0005). The smallest detectable difference was lower than the mean change in simplified PDUS variables. CONCLUSION A 12-joint PDUS assessment of RA joint inflammation may be a valid, feasible method for multicenter monitoring of therapeutic response to biologic agents.

Differential Th1/Th2 cytokine patterns in chronic arthritis: interferon gamma is highly expressed in synovium of rheumatoid arthritis compared with seronegative spondyloarthropathies.

OBJECTIVE To investigate possible differences in Th1 and Th2 cytokine mRNA expression in the synovial tissue (ST) of patients with rheumatoid arthritis (RA) and seronegative spondyloarthropathies (SpA) with diagnostic and/or pathogenic interest. METHODS Eleven RA patients and 14 SpA patients (10 with undifferentiated spondyloarthropathy (USpA), two with ankylosing spondylitis (AS) and two with psoriatic arthritis (PsA)) were included. Th1 (interferon γ, interleukin 2) and Th2 (interleukin 4, interleukin 5 and interleukin 10) cytokine mRNA levels from arthritic knee ST were quantified by using an optimised polymerase chain reaction method with a computerised analysis system. Protein levels of proinflammatory cytokines (interleukin 1, tumour necrosis factor α and interleukin 6) in synovial fluid were quantified with a specific ELISA test. RESULTS Th1 cytokines were detected in all of RA ST samples in contrast with 58% (interferon γ) and 71% (interleukin 2) of SpA samples. Th2 cytokines were expressed in 90% of RA ST samples, but the findings in SpA were interleukin 10 in 90%, interleukin 4 in 60% and interleukin 5 in 40% of ST samples. However, when the mRNA levels of each cytokine were quantified and corrected for T cell mRNA levels, only interferon γ levels were significantly higher in RA than in SpA (p<0.003). Thus, the Th1/Th2 cytokine ratio in RA was fivefold that of SpA. Synovial fluid interleukin 1β concentrations were higher in RA than in SpA (p<0.05); there were also higher synovial fluid levels of tumour necrosis factor α in RA than in SpA, but without statistical significance. CONCLUSION This study has detected both Th1 and Th2 cytokine gene expression in ST from RA and SpA patients. Synovium interferon γ mRNA levels and SF interleukin 1β protein levels were significantly higher in RA than in SpA, so reflecting the known proinflammatory activity of interferon γ through macrophage activation. Thus, the Th1 (interferon γ)/Th2 (interleukin 4) ratio is significantly higher in RA than in SpA ST. These data confirm previous studies on ST Th1/Th2 balance in RA and extend previous work in comparing ST RA with subgroups of SpA distinct of ReA.

Diagnosis of tuberculosis infection by tuberculin skin test and a whole-blood interferon-γ release assay in patients considered for anti–tumor necrosis factor-α therapy

To assess the performance of QuantiFERON®-TB Gold in-Tube (QFT-GIT; Cellestis, Carnegie, Australia) and tuberculin skin test (TST) in patients with immune-mediated inflammatory diseases (IMID), before anti-tumor necrosis factor-α (TNF-α) therapy, and to compare the results with those from the healthy population. Three hundred fourteen subjects (214 with IMID and 100 controls) underwent simultaneous QFT-GIT and TST. QFT-GIT was positive in 21% of IMID patients and in 16% of controls (P = 0.29). Among IMID patients, 21% tested positive by QFT-GIT and 24%, by TST (P = 0.30). Positive QFT-GIT results were not affected by immunosuppressive therapy (odds ratio, 0.78; 95% confidence interval [CI], 0.36-1.68; P = 0.52). Agreement between both tests in those patients who tested positive by one of the tests was 50% (95% CI, 37.2-62.8). QFT-GIT is useful for identifying IMID patients requiring treatment of latent tuberculosis before anti-TNF therapy. However, given the poor agreement between TST and QFT-GIT, we advocate a strategy of simultaneous testing to optimize diagnostic sensitivity.

A deletion at ADAMTS9-MAGI1 locus is associated with psoriatic arthritis risk

Objective Copy number variants (CNVs) have been associated with the risk to develop multiple autoimmune diseases. Our objective was to identify CNVs associated with the risk to develop psoriatic arthritis (PsA) using a genome-wide analysis approach. Methods A total of 835 patients with PsA and 1498 healthy controls were genotyped for CNVs using the Illumina HumanHap610 BeadChip genotyping platform. Genomic CNVs were characterised using CNstream analysis software and analysed for association using the χ2 test. The most significant genomic CNV associations with PsA risk were independently tested in a validation sample of 1133 patients with PsA and 1831 healthy controls. In order to test for the specificity of the variants with PsA aetiology, we also analysed the association to a cohort of 822 patients with purely cutaneous psoriasis (PsC). Results A total of 165 common CNVs were identified in the genome-wide analysis. We found a highly significant association of an intergenic deletion between ADAMTS9 and MAGI1 genes on chromosome 3p14.1 (p=0.00014). Using the independent patient and control cohort, we validated the association between ADAMTS9-MAGI1 deletion and PsA risk (p=0.032). Using next-generation sequencing, we characterised the 26 kb associated deletion. Finally, analysing the PsC cohort we found a lower frequency of the deletion compared with the PsA cohort (p=0.0088) and a similar frequency to that of healthy controls (p>0.3). Conclusions The present genome-wide scan for CNVs associated with PsA risk has identified a new deletion associated with disease risk and which is also differential from PsC risk.

Differing specificities and isotypes of anti-citrullinated peptide/protein antibodies in palindromic rheumatism and rheumatoid arthritis

BackgroundTo analyze differences in the recognition of anti-citrullinated peptide/protein antibody (ACPA) citrullinated epitopes and isotypes in patients with palindromic rheumatism (PR) and rheumatoid arthritis (RA).MethodsACPA fine specificities (citrullinated peptides of enolase, fibrin, and vimentin) and isotypes (IgG, IgM, and IgA) were analyzed in 54 patients with longstanding PR and 54 patients with established RA.ResultsCCP2 tested positive in 66.7% of patients with PR and RA. The ACPA distribution of fine specificities and isotypes differed between PR and RA patients. PR patients had a lower frequency of fine ACPA specificities than RA patients, which was significant in the case of a peptide derived from vimentin (PR 24.1% vs. 59.3% RA; p < 0.001). The mean number of ACPA specificities was lower in PR than in RA patients, and only 25.9% of PR patients recognized ≥2 additional specificities compared with 46.3% of RA patients. Significantly less isotype usage, especially IgA, was observed in PR patients.ConclusionThe ACPA immune response differed in patients with PR and RA, with fewer fine specificities and isotype usage in patients with PR. Some patients with PR may have impaired maturation of the B-cell response against citrullinated peptides with no progression to RA.

The beliefs of rheumatoid arthritis patients in their subcutaneous biological drug: strengths and areas of concern

Patients’ beliefs about their prescribed medication are an important factor influencing intentional non-adherence. This study describes rheumatoid arthritis (RA) patients’ beliefs about their subcutaneous (SC) biological medication through the Beliefs about Medicines Questionnaire (BMQ), and potential associations. As part of the ARCO study (Study on Adherence of Rheumatoid arthritis patients to subCutaneous and Oral drugs), patients completed the BMQ specifically for their SC biological medication, encompassing a necessity and a concerns scale. The medication possession ratio (MPR) was calculated to assess adherence to the SC biological medication. The BMQ was completed by 321 patients. Between 71.0 and 89.7% of patients agreed/strongly agreed with necessity scale statements, and only 7.2% had low necessity scores. Between 20.0 and 49.8% of patients agreed/strongly agreed with four of five concern scale statements, and 72.3% agreed/strongly agreed with the concern statement regarding long-term medication effects. The percentage with high concerns was 58.9%, and was higher in patients not satisfied with, or with less fulfillment of, tolerability expectations. Non-adherence percentages were, respectively, 13.8 and 13.0% (p = 0.919) in those with high or low necessity, and 16.0 and 10.6% (p = 0.171) in those with high or low concerns. Most patients were categorized as ‘ambivalent’ (58.5%; high necessity/high concerns) or ‘accepting’ (36.1%; high necessity/low concerns) of their SC biological medication. The BMQ identified patients’ concerns with their SC biological medication. Because patients’ concerns could influence non-adherence to medication and future outcomes, physicians should address this issue in the clinic by informing patients and setting clear expectations.

Correction to: The beliefs of rheumatoid arthritis patients in their subcutaneous biological drug: strengths and areas of concern

In the original publication, the family name of the last author was incorrect. The correct name should read as Jaime Calvo-Alén.

SAT0458 Identification of genetic variation specifically associated with psoriatic arthritis using genome-wide association studies

Background PsA has a higher heritability than PsV, indicating the existence of additional PsA-specific genetic factors. To date, however, the specific genetic basis underlying PsA is poorly understood. Objectives The objective the present study was to identify new genetic variation specifically associated with PsA risk. Methods In order to characterize the genetic basis of PsA, we performed a GWAS meta-analysis at the single-marker level as well as at the pathway level (GWPA). A cohort of 835 PsA patients and 1,558 controls from the Spanish population was genotyped for >550,000 SNPs. GWAS data from a second cohort of 1,430 PsA patients and 1,417 controls from the North American population was also used. In order to confirm the specificity of the new genetic variation associated with PsA risk, we analyzed the association with purely cutaneous psoriasis (PsC, n=614) and rheumatoid arthritis (RA, n=1,191). We performed a pharmacogenetic analysis to investigate the new PsA-specific pathways as a source for drug discovery in PsA. Results GWAS meta-analysis identified a new association between B3GNT2 gene and PsA (P<5e-08). In the GWAS pathway analysis, we identified and validated a total of 14 genetic pathways associated with PsA risk. From these, the glycosaminoglycan (GAG) metabolism pathway was also found to be significantly associated with PsA risk when directly contrasted to the PsC cohort as well as the RA cohort. At the functional level, we detected a significant differential expression of GAG metabolism pathway genes in blood samples from PsA patients compared to PsC patients. The pharmacogenetic analysis identified several FDA-approved drugs likely to modify the GAG pathway. Conclusions The present study represents an important step towards the characterization of the genetic factors specific to PsA risk. Disclosure of Interest None declared

Retraso diagnóstico y terapéutico de la artritis reumatoide y su relación con dispositivos asistenciales en Catalunya. Estudio AUDIT

OBJECTIVE Diagnosis and therapy of patients with early onset rheumatoid arthritis (RA) is influenced by accessibility to specialized care devices. We attempted to analyze the impact of their availability. METHODS We analyzed time related to diagnosis delay measuring: 1) Time from first clinical symptoms to the first visit with the Rheumatologist; 2) Time from referral to the first visit of Rheumatology; 3) Time between first symptom until final diagnosis; 4) time between first symptom until the initiation of the first disease-modifying antirheumatic drug (DMARD). The presence of these 6 rheumatology devices was defined: 1) early arthritis monographic clinics, 2) RA monographic clinics, 3) Mechanisms for fast programming, 4) Algorithms for referral from primary care (PC), 5) rheumatology consultation services in PC and 6) consulting services in PC. RESULTS The mean time from onset of symptoms to diagnosis or the establishment of a DMARD in RA patients in Catalonia is very long (11 months). Patients seen in rheumatology devices such as RA monographic clinics, rheumatology consultation in PC and specially in early arthritis clinics are treated early with DMARDs. CONCLUSION the existence of monographic clinics or consulting in primary care centers is essential to improve early care of RA patients.

AB0007 Genome-Wide Association Study of Clinical Phenotypes in Psoriatic Arthritis

Background Genome-wide association studies (GWAS) in Psoriatic Arthritis (PsA)patients and controls have allowed the identification of multiple variants associated with disease risk. To date, however, no GWAS for PsA phenotypes has been reported. Objectives The main objective of this study was to identify new genetic variation associated with clinical phenotypes in PsA. Methods A total of n=835 patients diagnosed with PsA using CASPAR criteria were recruited in the discovery stage and genotyped for >600,000 single nucleotide polymorphisms. GWAS were performed for clinical and biological phenotypes associated with joint and skin disease. After allelic association analysis, those SNPs with highest level of significance were analyzed in an independent cohort of n=414 PsA patients. Results In the GWAS stage, several genomic regions showing high evidence of association with different PsA phenotypes (P<5e-6) were identified, including axial disease, peripheral disease, bone proliferation, degree of radiological sacroileitis and the presence of syndesmophytes. Also, GWAS on cutaneous phenotypes identified two regions associated with nail disease and skin disease severity. Using the replication cohort, the association between one locus and peripheral pattern, and two loci with axial pattern were validated. Conclusions Usign a GWAS approach, new loci associated with axial and peripheral disease in PsA have been identified. Disclosure of Interest None declared