Background Remission is the current aim of treatment in rheumatoid arthritis (RA). Remission is ideally the absence of detectable disease and absence of structural and functional worsening over the time. Infra-clinical synovitis, detected by ultrasound, may persist in patients with remission leading to further structural damage.
Objectives The aim of this study was to assess the frequency of relapse after clinical remission and the value of US to predict this relapse.
Methods A prospective study of 30 patients followed-up for RA in remission was conducted. The remission was defined by a Disease Activity Score 28 joints (DAS28) ≤2,6 for at least 3 months under the same therapy. A B-mode and Power Doppler (PD) US examination was assessed by an experienced rheumatologist blinded to clinical data for 22 joints (wrists, 10 metacarpo-phalangeals, 10 proximal interphalangeals joints). A semi-quantitative scale running from 0 to 3 depending on US activity was attributed for each joint for PD. Patients were clinically controlled 3 to 6 months after performing the US. The variability of DAS28 was noted, it was considered significant if the p value <0,05.
Results The mean age of the thirty patients was 48 years-old (25 females, 5 males). All of them were in remission according to DAS28 with an average of 2,03 [1,13-2,6]. US examination showed synovial hypertrophy in B-mode in 80% of patients and PD signals in 56,7% of patients. The follow-up control was performed on average after 4 months for 27 patients. The variation of DAS28 from baseline was significant (p<0,005). In fact the DAS28 increased of 0,75 [0,10-3,1] for 20 patients, among them 14 were no longer in remission. The DAS28 remained stable for 2 patients and decreased for 5 others. For patients who have reactivation of RA, the mean US PD scale was 4,4, while it was 1,1 for patients who remained in remission. However, the difference wasn't significant (p=0,12).
Conclusions For patients in remission, persistent active synovitis in US is a risk factor for futur reactivation of the disease. PD monitoring in daily practice might lead to reduce disease relapses and structural damages.
Disclosure of Interest : None declared