Background High-resolution sonography enables assessment of intraarticular abnormalities of joints affected by rheumatoid arthritis (RA).Its use has been well described on international consensus (1).
Objectives The present study was undertaken to evaluate the association of physical examination (PE) findings with gray scale synovitis (GSS) and power Doppler signal (pD) in hands of RA patients.,
Methods Eighty-four RA patients (according to the 1987 American College of Rheumatology criteria) treated with disease-modifying antirheumatic drugs (DMARDs) were included in this prospective transversal study. PE of the hands (pain and/or edema) was performed by a rheumatologist unaware of the ultrasound findings. High resolution muskuloskeletal ultrasound (MSUS) – MyLab 60, Esaote, Genova, Italy, linear probe 6-18 MHz – was performed on the wrists, 2th and 3th metacarpophalangeal (MCP) and 2th and 3th proximal interphalangeal (PI) joints of both hands by two ultrassound-trained rheumatologists (unaware of clinical data) immmediately after PE. GSS and pD were searched and evaluated using a semi-quantitative scale (0-3). The sum of the individual joint scores for GSS and pD (score 10) was calculated and used to correlate with the clinical variables. Disease acitivity and disability were measured using Disease Activity Score in 28 joints (DAS28) and Health Assessment Questionnaire (HAQ), respectively. Mann-Whitney test and Spearman correlation coefficient (rS) were used for statistical analysis.
Results Clinical and demographic features of included patients were: mean age, 55.6±11.8 years; female gender, 79%; Caucasians, 85.7%; positive rheumatoid factor by nephelometry, 63%; median (interquartile range) disease duration 6 (2-13) years; mean ± SD DAS28, 4.55±1.62; mean ± SD HAQ score, 1.13±0.87. Interobserver agreement (measured by kappa values) for US examination varied from 0.53 to 0.86. We observed a significant association (P≤0.05) of the presence of articular edema with higher GSS and pD in all joints, except for the 3rd right PI. There was no association of pain on PE with GSS or pD in any of the evaluated joints. There was no significant correlation of GSS- and pD-score10 with DAS28 (rS=0.21, P=0.060 and rS=0.04, P=0.722, respectively), HAQ score (rS=-0.02, P=0.862 and rS=0.00, P=0.997), and tender joint count (rS=0.07, P=0.564 and rS=-0.20, P=0.078). However, there was a significant association of GSS- and pD score10 with the swollen joint count (rS=0.54, P<0.001 and rS=0.39, P<0.001).
Conclusions Our data show that only articular edema on PE is associated with proliferative (GSS) and microcirculatory (pD) findings on MSUS in RA patients. Isolated pain (without edema) does not reflect inflammatory ultrasound abnormalities in this group of patients.
Colebatch AN et al. EULAR recomendations for the use of imaging of the joints in the clinical management of rheumatoid arthritis. Ann Rheum Dis, 2013 Jun; 72(6):804-14.
Disclosure of Interest None declared