AB0283 Predictors of rheumatoid arthritis (RA): Quantitative and semi-quantitative sonographic measurements of peripheral joints
Authors: F.S. Machado, R.N.V. Furtado, R.D. Takahashi, A.L.P. Buosi, J. Natour
Journal: Annals of the Rheumatic Diseases (2013)

<h3>Background</h3> Sonographic quantitative and semi-quantitative measurements in peripheral joints of normal subjects are yet to be defined, as are sonographic predictors of RA. <h3>Objectives</h3> To estimate quantitative and semi-quantitative ultrasound measurements predictors of RA in small, medium and large joints. <h3>Methods</h3> A cross-sectional study was carried out involving 78 healthy volunteers (HV) and 60 patients with RA (ACR), matched for age group and gender. A “blind” radiologist used a My Lab 60 XVision machine (Esaote, Biomedica - Genova, Italy) with a linear trnasducer (6-18MHz) to evaluate 6.348 joint recesses. Quantitative measurements of synovial recess (QSR) (mm) and semi-quantitative measurements of synovial hyperplasia (SSH), Power Doppler (SPD) and bone erosion (SBE) (scores 0-3) were performed. To determine the chance to detect RA, ROC curve analysis for QSR measurements were performed (specificity 98.7%) and, for the semi-quantitative measures, an univariate logistic regression (expressed in odds ratio - OR) was carried out. <i>P</i> value &lt;0.05 was set as significant. <h3>Results</h3> The mean age (± SD) was 46.48 (9.14) and 43.89 (9.09), respectively for the HV and RA groups. The sample was homogeneous for gender, age group and skin color. <i>RA group:</i> mean disease duration was 7.89 years (± 6.76) and DAS-28 4.20 (± 1.71). Statistical difference was observed between groups for QSR (p&lt;0.013) for most of the joint recesses. <i>Mean (±SD) (mm) of QSR</i>, respectively for HV and RA groups (HV/RA), were: radiocarpal: 2.07 (0.56)/3.24 (1.24); distal radioulnar: 1.45 (0.37)/2.28 (1.11); ulnocarpal: 1.37 (0.59)/2.74 (1.76); dorsal 2nd metacarpophalangeal (MCP): 1.06 (0.53)/1.51 (0.96); palmar 2nd MCP: 0.88 (0.60)/1.40 (1.01); dorsal 3rd MCP: 0.81 (0.62)/1.24 (0.99); dorsal 2nd proximal interphalangeal (PIP): 0.46 (0.25)/0.76 (0.64); dorsal 3rd PIP: 0.44 (0.32)/0.83 (0.56); palmar 3rd PIP: 0.83 (0.27)/1.11 (0.55); coronoid fossa: 0.97 (1.06)/2.18 (2.27); olecranean fossa: 1.51 (1.17)/2.79 (2.65); posterior GH recess: 2.43 (0.45)/3.03 (1.29); knee: 2.21 (1.65)/3.95 (2.96); talocrural: 2.38 (1.13)/3.34 (1.99); talonavicular: 2.67 (1.10)/3.56 (1.50); subtalar: 2.15 (1.13)/3.07 (1.71); dorsal 5th MTP: 0.72 (0.70)/1.47 (1.11). Cutoff values of QSR specific of RA (AUC&gt;0,700) were: radiocarpal 3.78mm; ulnocarpal 3.07mm; distal radioulnar 2.21mm; dorsal 3rd PIP 1.19mm; knee 6.7mm and dorsal 5th MTP 2.33mm. For semi-quantitative measurements, progression from score 0 to 3, at the joint recesses with greater chance to detect RA were: <i>SSH:</i> ulnocarpal (OR=100, p=0.000); radiocarpal (OR=70, p=0.000); distal radioulnar (OR=43, p=0.000) and knee (OR=28, p&lt;0.000); <i>SPD:</i> radiocarpal (OR=66, p=0.000); <i>SBE:</i> radiocarpal (OR=324, p=0.000); lateral 5th MTP (OR=100, p=0.000); 2nd MCP (dorsal and radial) (OR=92, p=0.000) and ulnocarpal (OR=48, p=0.000). Inter-observer reliability (r) for quantitative and semi-quantitative measures ranged from 0.563 to 0.872 and 0.341 to 0.823, respectively. <h3>Conclusions</h3> Values of QSR were higher in RA patients compared with HV for most studied joint recesses. Also, quantitative measures specific of RA were found in almost all recesses. Semi-quantitative measurements analysis showed that the worst scores found at radiocarpal, ulnocarpal and lateral 5th MTP recesses increases the chance to detect RA. <h3>References</h3> K Ellegaard, 2007. M Szkudlarek, 2003. DG Disler, 2000. <h3>Disclosure of Interest</h3> None Declared