Overweight and obesity affect clinical assessment of synovitis in rheumatoid arthritis: comparison of ultrasonography and clinical exam.

OBJECTIVES: Body mass index (BMI) might affect rheumatoid arthritis (RA) outcomes. Clinical assessment of swollen joint count (SJC) might also be affected by obesity in terms of obesity-related excess adipose tissue. In this study, we compared ultrasonography (US) and clinical examination in assessing the effect of BMI on RA disease activity assessment. METHODS: This was a single-centre study including RA (ACR/EULAR criteria) patients. US assessment was performed by one trained rheumatologist blinded to clinical data. US synovitis was defined as grey-scale score ≥2 and/or power Doppler score ≥1. The primary outcome measure was difference in SJC (ΔSJC) between clinical and US assessment (US-clinical examination). The secondary outcome was to evaluate the difference between clinical and US assessment of the Disease Activity Score in 28 joints (ΔDAS28) in the 3 BMI subgroups according to the WHO classification. RESULTS: We included 76 RA patients (mean age 53.8 ± 11.8 years; 67% female). Overall, 28 (36.8%), 33 (43.4%) and 15 (19.7%) were normal weight, overweight and obese, respectively. Baseline characteristics did not differ between the 3 BMI subgroups. US-determined SJC was significantly higher than clinical-determined SJC for overweight and obese RA patients: p=0.001 and p=0.049, respectively. The DAS28 was higher with US than clinical examination within the overweight group only (p=0.002). One-way analysis of variance (ANOVA) revealed a significant difference between ΔDAS28 among the 3 BMI subgroups (p=0.046). CONCLUSIONS: In high BMI RA patients both SJC and DAS28 seem to be undervalued by clinical assessment when compared to US.

Shared genetic predisposition in rheumatoid arthritis-interstitial lung disease and familial pulmonary fibrosis.

Despite its high prevalence and mortality, little is known about the pathogenesis of rheumatoid arthritis-associated interstitial lung disease (RA-ILD). Given that familial pulmonary fibrosis (FPF) and RA-ILD frequently share the usual pattern of interstitial pneumonia and common environmental risk factors, we hypothesised that the two diseases might share additional risk factors, including FPF-linked genes. Our aim was to identify coding mutations of FPF-risk genes associated with RA-ILD.We used whole exome sequencing (WES), followed by restricted analysis of a discrete number of FPF-linked genes and performed a burden test to assess the excess number of mutations in RA-ILD patients compared to controls.Among the 101 RA-ILD patients included, 12 (11.9%) had 13 WES-identified heterozygous mutations in the TERT, RTEL1, PARN or SFTPC coding regions. The burden test, based on 81 RA-ILD patients and 1010 controls of European ancestry, revealed an excess of TERT, RTEL1, PARN or SFTPC mutations in RA-ILD patients (OR 3.17, 95% CI 1.53-6.12; p=9.45×10-4). Telomeres were shorter in RA-ILD patients with a TERT, RTEL1 or PARN mutation than in controls (p=2.87×10-2).Our results support the contribution of FPF-linked genes to RA-ILD susceptibility.

Electrocardiographic changes during exercise in acute hypoxia and susceptibility to severe high-altitude illnesses.

BACKGROUND: The goals of this study were to compare ECG at moderate exercise in normoxia and hypoxia at the same heart rate, to provide evidence of independent predictors of hypoxia-induced ECG changes, and to evaluate ECG risk factors of severe high-altitude illness. METHODS AND RESULTS: A total of 456 subjects performed a 20-minute hypoxia exercise test with continuous recording of ECG and physiological measurements before a sojourn above 4000 m. Hypoxia did not induce any conduction disorder, arrhythmias, or change in QRS axis. The amplitude of the P wave in V1 was lower in hypoxia than in normoxia. The amplitudes of the R, S, and T waves and the Sokolow index decreased in hypoxia. Under hypoxia, the amplitude of the ST segment decreased in II and V6 and increased in V1, the ST slope rose in V5 and V6, and the J point was lower in II, V5, and V6. Multivariate regression of hypoxic/normoxic ratios of electrophysiological parameters and clinical characteristics showed a correlation between the decrease in Sokolow index and T-wave amplitude in V5 with desaturation at exercise. Trained status and low body mass index were associated with a smaller decrease in T-wave amplitude in V5 and V6. Comparison of ECG between subjects suffering or not suffering from severe high-altitude illness failed to show any difference. CONCLUSIONS: During a hypoxia exercise test, a dose-dependent hypoxia-induced decrease in the amplitude of the P/QRS/T waves was observed. No standard ECG characteristic predicted the risk of developing severe high-altitude illness. Further studies are required to clarify the cause of these electric changes and their potential predictive role in cardiac events.

Identification of secreted phosphoprotein 1 gene as a new rheumatoid arthritis susceptibility gene.

OBJECTIVE: To evaluate the contribution of the SPP1 rs11439060 and rs9138 polymorphisms, previously reported as autoimmune risk variants, in the rheumatoid arthritis (RA) genetic background according to anti-citrullinated protein antibodies (ACPAs) status of RA individuals. METHODS: We analysed a total of 11,715 RA cases and 26,493 controls from nine independent cohorts; all individuals were genotyped or had imputed genotypes for SPP1 rs11439060 and rs9138. The effect of the SPP1 rs11439060 and rs9138 risk-allele combination on osteopontin (OPN) expression in macrophages and OPN serum levels was investigated. RESULTS: We provide evidence for a distinct contribution of SPP1 to RA susceptibility according to ACPA status: the combination of ≥3 SPP1 rs11439060 and rs9138 common alleles was associated mainly with ACPA negativity (p=1.29×10(-5), ORACPA-negative 1.257 (1.135 to 1.394)) and less with ACPA positivity (p=0.0148, ORACPA-positive 1.072 (1.014 to 1.134)). The ORs between these subgroups (ie, ACPA-positive and ACPA-negative) significantly differed (p=7.33×10(-3)). Expression quantitative trait locus analysis revealed an association of the SPP1 risk-allele combination with decreased SPP1 expression in peripheral macrophages from 599 individuals. To corroborate these findings, we found an association of the SPP1 risk-allele combination and low serum level of secreted OPN (p=0.0157), as well as serum level of secreted OPN correlated positively with ACPA production (p=0.005; r=0.483). CONCLUSIONS: We demonstrate a significant contribution of the combination of SPP1 rs11439060 and rs9138 frequent alleles to risk of RA, the magnitude of the association being greater in patients negative for ACPAs.

Associations between a scleroderma-specific gastrointestinal instrument and objective tests of upper gastrointestinal involvements in systemic sclerosis.

OBJECTIVES: UCLA-SCTC-GIT 2.0 is an instrument designed to evaluate gastrointestinal (GI) symptoms in systemic sclerosis (SSc). The objective of our study was to assess the associations between the upper GI (UGI) symptom scales (reflux and distention/bloating [D/B] scales) versus objective/laboratory studies. METHODS: Fifty-five patients with SSc were enrolled at 2 centres. Each patient completed the GIT 2.0 and had objective and laboratory tests. Correlations were assessed using the Spearman's test. We also assessed the average scores in patients with positive vs. negative tests and compared them using the t-test and Wilcoxon test. RESULTS: The mean (SD) age was 53.6 (11.8), 90% were women and 49% had limited SSc. The mean reflux and D/B scores were 0.82 and 1.25, respectively (moderate severity). The reflux scale had moderate correlations with upper GI objective evaluations (correlation coefficient ≥0.40) and was able to differentiate between patients with endoscopy proven esophagitis and manometric abnormalities (p=0.01 for both). D/B scores were numerically higher in patients with abnormal objective tests. The GIT 2.0 reflux and D/B scales had a high sensitivity ranging from 80% to 94% but very low specificity (range; 0-20%) based on objective gold standard GI measures. CONCLUSIONS: The GIT 2.0 reflux and D/B scales have a high sensitivity (range 80-94%) for UGI involvement. The GIT 2.0 instrument complements the objective tests for assessment of the UGI.

C8orf13-BLK is a genetic risk locus for systemic sclerosis and has additive effects with BANK1: results from a large french cohort and meta-analysis.

OBJECTIVE: Accumulating evidence suggests that B cells are involved in systemic sclerosis (SSc). BANK1 has been reproducibly reported to be associated with diffuse cutaneous SSc (dcSSc). BLK encodes another B cell signal transducer, and a functional variant at the C8orf13-BLK locus has been found to be associated with SSc in Caucasians. However, no independent replication has been reported, and there are discrepancies in the genotype-phenotype correlation between these studies in Caucasians and another study performed in the Japanese population. Therefore, in a large cohort of French Caucasians and using a meta-analysis of the available data, this study was undertaken to determine whether the C8orf13-BLK locus is associated with SSc, and to assess the possibility of interaction between BLK and BANK1 in SSc. METHODS: The C8orf13-BLK rs13277113 genotype was determined in 1,031 patients with SSc and 1,014 control subjects for whom BANK1 genotypes were available. Meta-analysis of the 3 available data sets (6,078 individuals) was also performed. RESULTS: Minor allele frequencies for rs13277113 revealed an association restricted to the dcSSc subtype (P = 0.012, odds ratio [OR] 1.29) in the French sample. Meta-analysis of the combined Caucasian populations showed an association of this genotype with both SSc (P = 0.0013, OR 1.16, 95% confidence interval [95% CI] 1.06-1.26) and dcSSc (P = 0.0012, OR 1.23, 95% CI 1.08-1.39). Inclusion of the Japanese population confirmed the overall association with the disease, with the strongest association observed with dcSSc (P = 3.27 × 10⁻5, OR 1.27). Secondary analysis in the French sample revealed additive effects between C8orf13-BLK and BANK1, mainly in the dcSSc subset. CONCLUSION: These results confirm C8orf13-BLK as an SSc risk locus. The strongest effects, and particularly additive effects, were observed in the interaction between C8orf13-BLK and BANK1 in the dcSSc subset.

Development and validation of French version of the UCLA Scleroderma Clinical Trial Consortium Gastrointestinal Tract Instrument.

OBJECTIVES: The UCLA Scleroderma Clinical Trial Consortium Gastrointestinal Tract Instrument (UCLA-SCTCGIT) 2.0 was developed to assess systemic sclerosis (SSc) associated gastrointestinal tract (GIT) symptoms severity and its impact on patients' well-being. Our objective was to translate the UCLA-GIT 2.0 from English to French and to evaluate the reliability and validity of the French version. METHODS: UCLA-GIT 2.0 was adapted into French using a formal forward-backward translation method and administered to 76 French speaking patients with SSc. The patients also completed the SF-36. We evaluated the internal consistency reliability and construct validity by exploring associations between the UCLA SCTC GIT 2.0 and SF-36 scales. Patients were also classified into two groups based on unintended weight loss within the past 6 months (≥5% vs. <5% of total body weight). RESULTS: Participants were mostly white (90%), female (81%) and had limited SSc (50%). Mean score of the UCLA-GIT 2.0 scales were: 0.35 for faecal soilage, 0.44 for diarrhoea, 0.45 for emotional well-being, 0.48 for both constipation and social functioning, 0.52 for reflux, and 0.95 for distension/bloating. The instrument had acceptable reliability (defined as Cronbach alpha≥0.69) except for the diarrhoea scale (alpha=0.56). The majority of hypothesized correlations were of moderate magnitude (coefficient≥0.30) and were in the appropriate direction. Patients with ≥5% unintended weight loss had worse UCLA-GIT scores in all scales (p<0.05 for distention/bloating scale). CONCLUSIONS: The French version of the UCLA-GIT 2.0 has acceptable psychometric properties and can be used in French speaking SSc patients.

Association study of 3 rheumatoid arthritis risk loci in systemic sclerosis in European Caucasian population.

INTRODUCTION: Accumulating evidences show that shared autoimmunity is critical for the pathogenesis of many inflammatory rheumatic conditions. Specific phenotype could arise from specific genes, and/or combination of genetic factors and environment. Systemic sclerosis (SSc) belongs to connective tissue disorders and recent data have highlighted strong associations with some autoimmunity genes shared with other autoimmune diseases. OBJECTIVES: To determine whether novel risk loci associated with rheumatoid arthritis (RA) may confer susceptibility to SSc. Single nucleotide polymorphism from CCL21, CD244 and CDK6 were tested for association. METHODS: SNPs harbouring association with RA, CCL21-rs2812378, CDK6-rs42041 and CD244-rs6682654 were genotyped in a cohort of 1031 SSc patients and 1014 controls. All individuals were of European Caucasian origin. RESULTS: The three polymorphisms were in Hardy-Weinberg equilibrium in the control population and allelic frequencies were similar to those expected in European populations. Allelic and genotypic frequencies for these three polymorphisms were found to be similar in SSc patients and controls. Moreover, sub-phenotype analyses in particular for subgroups having diffuse subcutaneous subtype, specific auto-antibodies or fibrosing alveolitis did not detect any difference between SSc patients and controls. CONCLUSIONS: These results obtained through a large cohort of European Caucasian SSc patients do not support the implication of CCL21, CD244 and CDK6 genes in the pathogenesis of SSc although these genes were recently identified as RA susceptibility genes.

Enthesopathy in rheumatoid arthritis and spondyloarthritis: An ultrasound study.

OBJECTIVE: We aimed to compare the prevalence of enthesopathy seen on ultrasonography (US) in spondyloarthritis (SpA) and rheumatoid arthritis (RA) and compared it to healthy controls. METHODS: All included patients with RA (2010 ACR/EULAR criteria) and SpA (ASAS criteria) and healthy controls underwent clinical and US evaluation of enthesis at seven sites (quadriceps, proximal and distal patellar, Achilles and triceps tendons, plantar aponeurosis and lateral epicondyle enthesis). The Glasgow Ultrasound Enthesitis Scoring System (GUESS) and the Madrid Sonographic Enthesitis Index (MASEI) scores were determined by two sonographers blinded to clinical data. RESULTS: We included 30 patients with RA (mean age: 55.7±14.8 years, mean disease duration 10.5±7.9years); 41 with SpA (mean age: 45.3±15.4 years, mean disease duration 9.2±8.7years) and 26 healthy controls (HC) (mean age: 50.4±17.3years). Patients with SpA and RA had similar prevalence of painful enthesis of examined sites (17% vs. 14%, non-significant [ns]), but more than among in healthy controls (3%, P<0.05 for RA and SpA comparison). Comparison between SpA and RA patients revealed that at least one US enthesis abnormality was found with similar frequency (46% and 48% sites [ns]) but both rheumatic diseases had higher frequency of US enthesis abnormality than HC (31%, P<0.05 for RA and SpA comparison). The mean MASEI score was 8.5±7.3 for RA patients, 7.8±6.5 for SpA patients (ns) and 3.4±2.8 for healthy controls (P<0.05 for RA and SpA comparison). Overall, 6 RA (20%) and 4 SpA (10%) patients had a MASEI score≥18 (ns). None of the healthy controls had a MASEI score≥18 (P<0.05 for RA and SpA comparison). The mean GUESS score was 5.8±3.1 and 6.3±3.9 for RA and SpA patients (ns), and 4.0±3.1 for healthy controls (P<0.01 vs. SpA and <0.05 vs. RA). CONCLUSIONS: RA and SpA patients did not differ in entheseal abnormalities seen on US. Such US features may have low specificity in inflammatory conditions affecting joints and enthesis such as SpA and RA.

Arthritis secondary to meningococcal disease: A case series of 7 patients.

Arthritis secondary to invasive meningococcemia is rare and has been described as a direct result of bacteremia or as immunoallergic-type arthritis, related to the immune complex. Only a few case series have been reported.This multicenter study aimed to describe the clinical characteristics and therapeutic outcomes of arthritis secondary to meningococcal infection.We performed a 5-year retrospective study. We included all patients with inflammatory joint symptoms and proven meningococcal disease defined by the identification of Neisseria meningitidis in blood, cerebrospinal fluid, or synovial fluid. Septic arthritis was defined by the identification of N meningitidis in joint fluid. Immune-mediated arthritis was considered to be arthritis occurring after at least 1 day of invasive meningococcal disease without positive joint fluid culture.A total of 7 patients (5 males) with joint symptoms and meningococcal disease were identified. The clinical presentation was mainly oligoarticular and the knee was the most frequent joint site. Five patients had septic arthritis and 4 had immune-mediated arthritis; 2 had septic arthritis followed by immune-mediated arthritis. Immune-mediated arthritis occurred 3 to 7 days after meningococcal meningitis, and treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) led to improvement without complications.Physicians must be vigilant to the different clinical presentations in patients with arthritis associated with invasive meningococcal disease. If immune-mediated arthritis is suspected, NSAIDs are usually efficient.

Positron emission tomography and computed tomography angiography for the diagnosis of giant cell arteritis: A real-life prospective study.

The use of 18F-fluoro-deoxyglucose positron emission tomography scan (FDG-PET) and computed tomography angiography (CTA) to improve accuracy of diagnosis of giant cell arteritis (GCA) is a very important clinical need. We aimed to compare the diagnostic performance of FDG-PET and CTA in patients with GCA.FDG-PET and CTA were acquired in all consecutive patients suspected for GCA. Results of FDG-PET and CTA were compared with the final diagnosis based on clinical judgment, temporal artery biopsy (TAB) findings, and ACR criteria. Sensitivity, specificity, and positive and negative predictive values (PPV, NPV) were calculated for each method.Twenty-four patients suspected for GCA were included. Fifteen (62.5%) were ultimately diagnosed as having GCA. Among them, all fulfilled ACR criteria and 6 had biopsy-proven GCA. Strong FDG uptake in large vessels was found in 10 patients who all had GCA. Mean maximal standard uptake values (SUVmax) per patient measured at all the arterial territories were of 3.7 (range: 2.8-4.7). FDG uptake was negative in 14 patients including 9 and 5 patients without and with GCA, respectively. Mural thickening suggestive of aortitis or branch vessel arteritis was observed on CTA in 11 patients with and 2 patients without GCA. No mural thickening was observed in 11 patients including 7 patients without and 4 patients with GCA. Overall, sensitivity was 66.7% and 73.3%, specificity was 100% and 84.6%, NPV was 64.3% and 64.6%, and PPV was 100% and 84.6% of FDG-PET and CTA, respectively.Both FDG-PET and CTA have a strong diagnostic yield for the diagnosis of GCA. FDG-PET appeared to have a higher PPV as compared to CTA and may be the preferred noninvasive technique to explore patients with suspected GCA.

Epistatic interaction between BANK1 and BLK in rheumatoid arthritis: results from a large trans-ethnic meta-analysis.

BACKGROUND: BANK1 and BLK belong to the pleiotropic autoimmune genes; recently, epistasis between BANK1 and BLK was detected in systemic lupus erythematosus. Although BLK has been reproducibly identified as a risk factor in rheumatoid arthritis (RA), reports are conflicting about the contribution of BANK1 to RA susceptibility. To ascertain the real impact of BANK1 on RA genetic susceptibility, we performed a large meta-analysis including our original data and tested for an epistatic interaction between BANK1 and BLK in RA susceptibility. PATIENTS AND METHODS: We investigated data for 1,915 RA patients and 1,915 ethnically matched healthy controls genotyped for BANK1 rs10516487 and rs3733197 and BLK rs13277113. The association of each SNP and RA was tested by logistic regression. Multivariate analysis was then used with an interaction term to test for an epistatic interaction between the SNPs in the 2 genes. RESULTS: None of the SNPs tested individually was significantly associated with RA in the genotyped samples. However, we detected an epistatic interaction between BANK1 rs3733197 and BLK rs13277113 (P(interaction)  = 0.037). In individuals carrying the BLK rs13277113 GG genotype, presence of the BANK1 rs3733197 G allele increased the risk of RA (odds ratio 1.21 [95% confidence interval 1.04-1.41], P = 0.015. Combining our results with those of all other studies in a large trans-ethnic meta-analysis revealed an association of the BANK1 rs3733197 G allele and RA (1.11 [1.02-1.21], P = 0.012). CONCLUSION: This study confirms BANK1 as an RA susceptibility gene and for the first time provides evidence for epistasis between BANK1 and BLK in RA. Our results illustrate the concept of pleiotropic epistatic interaction, suggesting that BANK1 and BLK might play a role in RA pathogenesis.

Independent replication and meta analysis of association studies establish TNFSF4 as a susceptibility gene preferentially associated with the subset of anticentromere-positive patients with systemic sclerosis.

OBJECTIVE: Independent replication with large cohorts and metaanalysis of genetic associations are necessary to validate genetic susceptibility factors. The known tumor necrosis factor (ligand) superfamily, member 4 gene (TNFSF4) systemic lupus erythematosus (SLE) risk locus has been found to be associated with systemic sclerosis (SSc) in 2 studies, but with discrepancies between them for genotype-phenotype correlation. Our objective was to validate TNFSF4 association with SSc and determine the subset with the higher risk. METHODS: Known SLE and SSc TNFSF4 susceptibility variants (rs2205960, rs1234317, rs12039904, rs10912580, and rs844648) were genotyped in 1031 patients with SSc and 1014 controls of French white ancestry. Genotype-phenotype association analysis and meta analysis of available data were performed, providing a population study of 4989 patients with SSc and 4661 controls, all of European white ancestry. RESULTS: Allelic and genotypic associations were observed for the 5 single-nucleotide polymorphisms (SNP) with the subset of patients with SSc who are positive for anticentromere antibodies (ACA) and only a trend for association with SSc and limited cutaneous SSc. Rs2205960 exhibited the strongest allelic association in ACA+ patients with SSc [p = 0.0015; OR 1.37 (1.12-1.66)], with significant intra-cohort association when compared to patients with SSc positive for ACA. Metaanalysis confirmed overall association with SSc but also raised preferential association with the ACA+ subset and strongest effect with rs2205960 [T allele p = 0.00013; OR 1.33 (1.15-1.54) and TT genotype p = 0.00046; OR 2.02 (1.36-2.98)]. CONCLUSION: We confirm TNFSF4 as an SSc susceptibility gene and rs2205960 as a putative causal variant with preferential association in the ACA+ SSc subphenotype.

Association study of ITGAM, ITGAX, and CD58 autoimmune risk loci in systemic sclerosis: results from 2 large European Caucasian cohorts.

OBJECTIVE: Accumulating evidence shows that shared autoimmunity is critical for the pathogenesis of many autoimmune diseases. Systemic sclerosis (SSc) belongs to the connective tissue disorders, and recent data have highlighted strong associations with autoimmunity genes shared with other autoimmune diseases. To determine whether novel risk loci associated with systemic lupus erythematosus or multiple sclerosis may confer susceptibility to SSc, we tested single-nucleotide polymorphisms (SNP) from ITGAM, ITGAX, and CD58 for associations. METHODS: SNP harboring associations with autoimmune diseases, ITGAM rs9937837, ITGAX rs11574637, and CD58 rs12044852, were genotyped in 2 independent cohorts of European Caucasian ancestry: 1031 SSc patients and 1014 controls from France and 1038 SSc patients and 691 controls from the USA, providing a combined study population of 3774 individuals. ITGAM rs1143679 was additionally genotyped in the French cohort. RESULTS: The 4 polymorphisms were in Hardy-Weinberg equilibrium in the 2 control populations, and allelic frequencies were similar to those expected in European Caucasian populations. Allelic and genotypic frequencies for these 3 SNP were found to be statistically similar in SSc patients and controls. Subphenotype analyses for subgroups having diffuse cutaneous subtype disease, specific autoantibodies, or fibrosing alveolitis did not reveal any difference between SSc patients and controls. CONCLUSION: These results obtained through 2 large cohorts of SSc patients of European Caucasian ancestry do not support the implication of ITGAM, ITGAX, and CD58 genes in the genetic susceptibility of SSc, although they were recently identified as autoimmune disease risk genes.