Objectives To identify and characterize subclinical synovitis in patients with rheumatoid arthritis (RA) in clinical remission using Power Doppler Ultrasound and immunohistology
Methods Prospective study with a 12- month follow-up. We will select patients with RA who are in clinical remission (defined as DAS28 <2.6) as evaluated by two rheumatologists. Clinical, epidemiological, demographic and serological data will be analyzed. Patients will undergo ultrasonography of both knees and hands (wrists, metacarpophalangeal [MCP], proximal interphalangeal [PIP], flexor and extensor tendons of the hand). Sonography findings were quantified as follows: synovial hypertrophy (grades 0-3) and power Doppler signal (grades 0-3). A portable ultrasound scanner (Esaote MyLab25) with a linear probe of 12 MHz was employed.
Patients with active synovitis (synovial hypertrophy plus power doppler signal) will undergo synovial biopsy by arthroscopy or ultrasound-guided, depending on the size of the target joint. The correlation of Power Doppler signal, vascular patterns, the cellular infiltrate and cytokine expression in synovial tissue with the development of bone erosions assessed by MRI at 12 months will be performed, in order to identify prognostic markers.
The ultimate goal is to recruit a total of 100 patients and 60 synovial biopsies. We here present the ultrasound results in the patients recruited so far.
Results 42 patients have been recruited so far (35 women and 7 men with a mean age of 54 + -12.2 years and a mean disease duration of 117.3 + -88.3 months). Sixty-seven per cent and 76.2% of patients were positive for RF and ACPA, respectively. All patients were treated with DMARD and 42.9% were also in biological treatment. 88.1% of patients had synovial hypertrophy and 66.7% had Power Doppler signal. The most affected joint (with power Doppler signal) was the wrist (33.3%), followed by the 2nd MCP (9.6%). Patients with active synovitis had DAS28 (mean 2.26 versus 1.93, P = 0.016) and weight (mean 68.5 kg versus 59.3 kg, P = 0.018) significantly higher than patients without Power Doppler signal. No significant differences between patients treated with DMARDs and biologic therapy were found.
Conclusions These preliminary results show that two-thirds of patients with RA in clinical remission exhibit power Doppler signal. The DAS28 was significantly higher in patients with active synovitis. No differences were found regarding baseline treatment.
Disclosure of Interest None Declared