Magnetic resonance imaging in rheumatoid arthritis: summary of OMERACT activities, current status, and plans

Complementing the 3 papers that precede it, this paper explains the rationale for the activities of an OMERACT working party on magnetic resonance imaging (MRI) evaluation of rheumatoid arthritis (RA), sets out provisional recommendations for the acquisition and scoring of MRI of the hand and wrist in RA, and delineates some of the many residual problems that need to be addressed.     

Biomarkers of inflammation in patients with unclassified polyarthritis and early rheumatoid arthritis. Relationship to disease activity and radiographic outcome

OBJECTIVE: To determine plasma interleukin 6 (pIL-6), plasma vascular endothelial growth factor (pVEGF), and serum (s) YKL-40 in patients with early rheumatoid arthritis (RA) and unclassified polyarthritis (PA), and investigate their relationship with radiographic outcome. METHODS: pIL-6 and pVEGF were determined by ELISA and sYKL-40 by an in-house radioimmunoassay in 51 patients with early RA and 21 with PA. Patients were followed with clinical and biochemical measurement every month for 2 years. Conventional radiographs of hands, wrists, and forefeet were scored according to the Larsen method, and magnetic resonance imaging of 2nd to 5th metacarpophalangeal joints of the dominant hand were evaluated for presence or absence of bone erosions. RESULTS: Baseline pIL-6, pVEGF, sYKL-40, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were elevated in RA patients compared to healthy persons (p < 0.001), but were not in patients with PA. Patients with early RA had higher pIL-6 (p = 0.007), pVEGF (p = 0.02), and sYKL-40 (p = 0.024) compared to PA patients. pIL-6, sYKL-40, CRP, and ESR but not pVEGF decreased in patients that responded to treatment after 2 years. The mean value of pIL-6 during the first and second year were higher in patients with early RA with progression in bone erosions (n = 14) compared to early RA patients without progression (n = 30; first year 8.4 vs 2.8 ng/l, p = 0.04; second year 6.1 vs 3.6 ng/l, p = 0.03). CONCLUSION:Plasma IL-6 was the only biomarker related to treatment response and progressive erosive disease in patients with early RA, but it may not give additional information compared to CRP in relation to disease activity and treatment response.