Ultrasound is more reliable than inflammatory parameters to evaluate disease activity in patients with RA receiving tocilizumab therapy

The target of treatment for rheumatoid arthritis (RA) is to keep low disease activity or remission. Tocilizumab can fully inhibit interleukin-6 and C reactive protein (CRP) production. The goal of the study is to search whether tocilizumab treatment compared with adalimumab treatment had the similar effect on sonography and inflammatory parameters in patients with RA. We compared ultrasound scores and inflammatory parameters between patients with RA receiving tocilizumab therapy and those receiving adalimumab therapy. Power Doppler (PD) ultrasound and grayscale synovial hypertrophy on bilateral radiocarpal joints were performed. Inflammatory mediators and ultrasound scores were compared by independent t-test between the adalimumab and tocilizumab groups. 65 patients with RA (32 tocilizumab and 33 adalimumab) were included. Between the two groups, there were no significant differences in age, gender, rheumatoid factors and anticyclic citrullinated peptide antibody. Following biological therapy, the ultrasound score was 2.33 in the tocilizumab group and 2.08 in the adalimumab group (p=0.570), while the erythrocyte sedimentation rate, CRP and Disease Activity Score in 28 joints (DAS28) were lower in the tocilizumab group. So ultrasound scores between the two groups were not significantly different, but the laboratory parameters and DAS28 were lower in the tocilizumab group than in the adalimumab group. Hence, to assess disease activity cannot be based only on clinical evaluations, so we suggest PD ultrasound to be used for all patients on tocilizumab therapy and reflect the true disease activity in these patients.