Gérard Chalès

Evaluation of several ultrasonography scoring systems for synovitis and comparison to clinical examination: results from a prospective multicentre study of rheumatoid arthritis

Objectives To evaluate different global ultrasonographic (US) synovitis scoring systems as potential outcome measures of rheumatoid arthritis (RA) according to the Outcome Measures in Rheumatoid Arthritis Clinical Trials (OMERACT) filter. Methods To study selected global scoring systems, for the clinical, B mode and power Doppler techniques, the following joints were evaluated: 28 joints (28-joint Disease Activity Score (DAS28)), 20 joints (metacarpophalangeals (MCPs) + metatarsophalangeals (MTPs)) and 38 joints (28 joints + MTPs) using either a binary (yes/no) or a 0–3 grade. The study was a prospective, 4-month duration follow-up of 76 patients with RA requiring anti-tumour necrosis factor (TNF) therapy (complete follow-up data: 66 patients). Intraobserver reliability was evaluated using the intraclass correlation coefficient (ICC), construct validity was evaluated using the Cronbach α test and external validity was evaluated using level of correlation between scoring system and C reactive protein (CRP). Sensitivity to change was evaluated using the standardised response mean. Discriminating capacity was evaluated using the standardised mean differences in patients considered by the doctor as significantly improved or not at the end of the study. Results Different clinimetric properties of various US scoring systems were at least as good as the clinical scores with, for example, intraobserver reliability ranging from 0.61 to 0.97 versus from 0.53 to 0.82, construct validity ranging from 0.76 to 0.89 versus from 0.76 to 0.88, correlation with CRP ranging from 0.28 to 0.34 versus from 0.28 to 0.35 and sensitivity to change ranging from 0.60 to 1.21 versus from 0.96 to 1.36 for US versus clinical scoring systems, respectively. Conclusion This study suggests that US evaluation of synovitis is an outcome measure at least as relevant as physical examination. Further studies are required in order to achieve optimal US scoring systems for monitoring patients with RA in clinical trials and in clinical practice.

The ability of synovitis to predict structural damage in rheumatoid arthritis: a comparative study between clinical examination and ultrasound

Objectives To evaluate synovitis (clinical vs ultrasound (US)) to predict structural progression in rheumatoid arthritis (RA). Methods Patients with RA. Study design Prospective, 2-year follow-up. Data collected Synovitis (32 joints (2 wrists, 10 metacarpophalangeal, 10 proximal interphalangeal, 10 metatarsophalangeal)) at baseline and after 4 months of therapy by clinical, US grey scale (GS-US) and power doppler (PD-US); x-rays at baseline and at year 2. Analysis Measures of association (OR) were tested between structural deterioration and the presence of baseline synovitis, or its persistence, after 4 months of therapy using generalised estimating equation analysis. Results Structural deterioration was observed in 9% of the 1888 evaluated joints in 59 patients. Baseline synovitis increased the risk of structural progression: OR=2.01 (1.36–2.98) p<0.001 versus 1.61 (1.06–2.45) p=0.026 versus 1.75 (1.18–2.58) p=0.005 for the clinical versus US-GS versus US-PD evaluation, respectively. In the joints with normal baseline examination (clinical or US), an increased probability for structural progression in the presence of synovitis for the other modality was also observed (OR=2.16 (1.16–4.02) p=0.015 and 3.50 (1.77–6.95) p<0.001 for US-GS and US-PD and 2.79 (1.35–5.76) p=0.002) for clinical examination. Persistent (vs disappearance) synovitis after 4 months of therapy was also predictive of subsequent structural progression. Conclusions This study confirms the validity of synovitis for predicting subsequent structural deterioration irrespective of the modality of examination of joints, but also suggests that both clinical and ultrasonographic examinations may be relevant to optimally evaluate the risk of subsequent structural deterioration.

Fractal dimension of trabecular bone: comparison of three histomorphometric computed techniques for measuring the architectural two‐dimensional complexity

Trabecular bone has been reported as having two‐dimensional (2‐D) fractal characteristics at the histological level, a finding correlated with biomechanical properties. However, several fractal dimensions (D) are known and computational ways to obtain them vary considerably. This study compared three algorithms on the same series of bone biopsies, to obtain the Kolmogorov, Minkowski–Bouligand, and mass‐radius fractal dimensions. The relationships with histomorphometric descriptors of the 2‐D trabecular architecture were investigated. Bone biopsies were obtained from 148 osteoporotic male patients. Bone volume (BV/TV), trabecular characteristics (Tb.N, Tb.Sp, Tb.Th), strut analysis, star volumes (marrow spaces and trabeculae), inter‐connectivity index, and Euler–Poincaré number were computed. The box‐counting method was used to obtain the Kolmogorov dimension (Dk), the dilatation method for the Minkowski–Bouligand dimension (DMB), and the sandbox for the mass‐radius dimension (DMR) and lacunarity (L). Logarithmic relationships were observed between BV/TV and the fractal dimensions. The best correlation was obtained with DMR and the lowest with DMB. Lacunarity was correlated with descriptors of the marrow cavities (ICI, star volume, Tb.Sp). Linear relationships were observed among the three fractal techniques which appeared highly correlated. A cluster analysis of all histomorphometric parameters provided a tree with three groups of descriptors: for trabeculae (Tb.Th, strut); for marrow cavities (Euler, ICI, Tb.Sp, star volume, L); and for the complexity of the network (Tb.N and the three Ds). A sole fractal dimension cannot be used instead of the classic 2‐D descriptors of architecture; D rather reflects the complexity of branching trabeculae. Computation time is also an important determinant when choosing one of these methods. Copyright

Reproducibility of joint swelling assessments in long-lasting rheumatoid arthritis: Influence on disease activity score-28 values (SEA-repro study part I)

Objectives. To evaluate the reproducibility of clinical synovitis assessments in rheumatoid arthritis and the effect of variability on the Disease Activity Score-28 (DAS28). Methods. Seven healthcare professionals from different cities examined the same patients with active non-early rheumatoid arthritis (RA; duration > 4 yrs), for whom a treatment change was being considered. There was no training session and the examination was to be performed as quickly as possible. The healthcare professionals assessed the 28 joints of the DAS28 in 7 patients (196 joints), then reexamined the same 28 joints in 4 of these 7 patients (112 joints), who had been rendered unrecognizable. Then 7 sonographers examined each of the 7 patients twice, using B-mode and power Doppler ultrasound (PD). The reference standards were presence of synovitis according to at least 50% of clinical examiners and 50% of sonographers. Agreement was assessed by Cohen’s kappa statistic. Results. Intraobserver reliability ranged from 0.31 (least experienced research technician) to 0.77 (most experienced physician). Interobserver reliability ranged from 0.18 to 0.62. The largest difference between the lowest and the highest swollen joint counts in the same patient was 15, and the greatest variation in the DAS28 score was 0.92. Agreement between clinical and sonographic reference standards was 0.46, 0.37, and 0.36 for B-mode, PD, and both, respectively. Conclusion. Clinical inter- and intraobserver reliability is highly dependent on the examiner. Consequences on the DAS28 score can be substantial. Agreement with sonography is poor when both B-mode and PD are used but seems better, although low, when B-mode is used alone.

Bone status in a mouse model of genetic hemochromatosis

SummaryGenetic hemochromatosis is a cause of osteoporosis; mechanisms leading to iron-related bone loss are not fully characterized. We assessed the bone phenotype of HFE−/− male mice, a mouse model of hemochromatosis. They had a phenotype of osteoporosis with low bone mass and alteration of the bone microarchitecture.IntroductionGenetic hemochromatosis is a cause of osteoporosis. However, the mechanisms leading to iron-related bone loss are not fully characterized. Recent human data have not supported the hypothesis of hypogonadism involvement. The direct role of iron on bone metabolism has been suggested.MethodsOur aim was to assess the bone phenotype of HFE−/− male mice, a mouse model of human hemochromatosis, by using microcomputed tomography and histomorphometry. HFE−/− animals were sacrificed at 6 and 12 months and compared to controls.ResultsThere was a significant increase in hepatic iron concentration and bone iron content in HFE−/− mice. No detectable Perls’ staining was found in the controls’ trabeculae. Trabecular bone volume (BV/TV) was significantly lower in HFE−/− mice at 6 and 12 months compared to the corresponding wild-type mice: 9.88 ± 0.82% vs 12.82 ± 0.61% (p = 0.009) and 7.18 ± 0.68% vs 10.4 ± 0.86% (p = 0.015), respectively. In addition, there was an impairment of the bone microarchitecture in HFE−/− mice. Finally, we found a significant increase in the osteoclast number in HFE−/− mice: 382.5 ± 36.75 vs 273.4 ± 20.95 ¢/mm2 (p = 0.004) at 6 months and 363.6 ± 22.35 vs 230.8 ± 18.7 ¢/mm2 (p = 0.001) at 12 months in HFE−/− mice vs controls.ConclusionOur data show that HFE−/− male mice develop a phenotype of osteoporosis with low bone mass and alteration of the microarchitecture. They suggest that there is a relationship between bone iron overload and the increase of the osteoclast number in these mice. These findings are in accordance with clinical observations in humans exhibiting genetic hemochromatosis and support a role of excess iron in relation to genetic hemochromatosis in the development of osteoporosis in humans.

Reproducibility of Joint Swelling Assessment by Sonography in Patients with Long-lasting Rheumatoid Arthritis (SEA-Repro Study Part II)

Objective. To evaluate the intraobserver and interobserver reproducibility of B-mode and power Doppler (PD) sonography in patients with active long-standing rheumatoid arthritis (RA) comparatively with clinical data. Methods. In each of 7 patients being considered for a change in their RA treatment regimen, 7 healthcare professionals examined the 28 joints used in the Disease Activity Score 28-joint count (DAS28). Then 7 sonographers examined each of the 7 patients twice, using previously published B-mode and PD grading systems. The clinical reference standard was presence of synovitis according to at least 4/7 examiners. The sonographic reference standard was at least grade 1 (ALG1) or 2 (ALG2) synovitis according to at least 4/7 sonographers. Interobserver reproducibility of sonography was assessed versus the sonographer having the best intraobserver reproducibility. Agreement was measured by Cohen’s kappa statistic. Results. Intraobserver and interobserver reproducibility of B-mode and PD used separately was fair to good. Agreement between clinicians and sonographers at all sites using B-mode, PD, and both was 0.46, 0.37, and 0.36, respectively, for grade 1 synovitis; and 0.58, 0.19, and 0.19 for grade 2 synovitis. The number of joints with synovitis was smaller by physical examination (36.7%) than by B-mode with ALG1 (58.6%; p < 0.001). The number of joints with synovitis was higher by physical examination than by PD with both ALG1 (17.8%; p < 0.0001) and ALG2 (6.6%; p < 0.0001). Conclusion. PD findings explain most of the difference between clinical and sonographic joint assessments for synovitis in patients with long-standing RA.

Prevalence of gout in the adult population of France

To estimate adult gout prevalence in France.

Risk of cutaneous adverse events with febuxostat treatment in patients with skin reaction to allopurinol. A retrospective, hospital-based study of 101 patients with consecutive allopurinol and febuxostat treatment

OBJECTIVE To investigate the cutaneous tolerance of febuxostat in gouty patients with skin intolerance to allopurinol. METHODS We identified all gouty patients who had sequentially received allopurinol and febuxostat in the rheumatology departments of 4 university hospitals in France and collected data from hospital files using a predefined protocol. Patients who had not visited the prescribing physician during at least 2 months after febuxostat prescription were excluded. The odds ratio (OR) for skin reaction to febuxostat in patients with a cutaneous reaction to allopurinol versus no reaction was calculated. For estimating the 95% confidence interval (95% CI), we used the usual Wald method and a bootstrap method. RESULTS In total, 113 gouty patients had sequentially received allopurinol and febuxostat; 12 did not visit the prescribing physician after febuxostat prescription and were excluded. Among 101 patients (86 males, mean age 61±13.9 years), 2/22 (9.1%) with a history of cutaneous reactions to allopurinol showed skin reactions to febuxostat. Two of 79 patients (2.5%) without a skin reaction to allopurinol showed skin intolerance to febuxostat. The ORs were not statistically significant with the usual Wald method (3.85 [95% CI 0.51-29.04]) or bootstrap method (3.86 [95% CI 0.80-18.74]). CONCLUSION The risk of skin reaction with febuxostat seems moderately increased in patients with a history of cutaneous adverse events with allopurinol. This moderate increase does not support the cross-reactivity of the two drugs.

Identification of patients with gout: elaboration of a questionnaire for epidemiological studies

Objectives In France, the prevalence of gout is currently unknown. We aimed to design a questionnaire to detect gout that would be suitable for use in a telephone survey by non-physicians and assessed its performance. Methods We designed a 62-item questionnaire covering comorbidities, clinical features and treatment of gout. In a case–control study, we enrolled patients with a history of arthritis who had undergone arthrocentesis for synovial fluid analysis and crystal detection. Cases were patients with crystal-proven gout and controls were patients who had arthritis and effusion with no monosodium urate crystals in synovial fluid. The questionnaire was administered by phone to cases and controls by non-physicians who were unaware of the patient diagnosis. Logistic regression analysis and classification and regression trees were used to select items discriminating cases and controls. Results We interviewed 246 patients (102 cases and 142 controls). Two logistic regression models (sensitivity 88.0% and 87.5%; specificity 93.0% and 89.8%, respectively) and one classification and regression tree model (sensitivity 81.4%, specificity 93.7%) revealed 11 informative items that allowed for classifying 90.0%, 88.8% and 88.5% of patients, respectively. Conclusions We developed a questionnaire to detect gout containing 11 items that is fast and suitable for use in a telephone survey by non-physicians. The questionnaire demonstrated good properties for discriminating patients with and without gout. It will be administered in a large sample of the general population to estimate the prevalence of gout in France.

Improving agreement in assessment of synovitis in rheumatoid arthritis.

OBJECTIVE Synovitis assessment through evaluation of swollen joints is integral in steering treatment decisions in rheumatoid arthritis (RA). However, there is high inter-observer variation. The objective was to assess if a short collegiate consensus would improve swollen joint agreement between rheumatologists and whether this was affected by experience. METHODS Eighteen rheumatologists from French university rheumatology units participated in three 30 minutes rounds over a half day meeting evaluating joint counts of RA patients in small groups, followed by short consensus discussions. Agreement was evaluated at the end of each round as follows: (i) global agreement of swollen joints (ii) swollen joint agreement according to level of experience of the rheumatologist (iii) swollen joint count and (iv) agreement of disease activity state according to the Disease Activity Score (DAS28). Agreement was calculated using percentage agreement and kappa. RESULTS Global agreement of swollen joints failed to improve (kappa 0.50 to 0.52) at the joint level. Agreement between seniors did not improve but agreement between newly qualified rheumatologists and their senior peer, which was initially poor (kappa 0.28), improved significantly (to 0.54) at the end of the consensus exercises. Concordance of DAS28 activity states improved from 71% to 87%. CONCLUSION Consensus exercises for swollen joint assessment is worthwhile and may potentially improve agreement between clinicians in clinical synovitis and disease activity state, benefit was mostly observed in newly qualified rheumatologists.