A study on fibronectin, which is synthesized in response to inflammatory process of joint destruction, can be of great value in identifying the mechanism of inflammation or disease activity of rheumatoid arthritis (RA). This study attempts to measure the concentrations of total fibronectin in synovial fluid of patients with RA and osteoarthritis (OA), and compare it with the clinical disease activity parameters of RA available. A total 68 patients suffering from knee pain and joint effusion was examined. Synovial fluids of thirty-eight RA patients and thirty OA patients were measured by using monoclonal fibronectin antibody. Cross-sectional analysis was undertaken to correlate the fibronectin levels of the RA patients with the clinical disease activity parameters available. RESULTS: 1. Mean synovial fibronectin level of RA (148.4+/-72.6 microgram/ml) was significantly higher than that of OA (39.5+/-16.9 microgram/ml)(p<0.001). 2. The fibronectin levels in RA do not seem to have significant relationship with the parameters such as disease duration, the duration of morning stiffness, Ritchie index, ESR, CRP, and rheumatoid factor. CONCLUSION: In conclusion, the synovial total fibronectin concentration can clearly distinguish RA from OA. However, it would be unlikely to be used as a parameter of disease activity.
Arthritis, Rheumatoid* ; Cross-Sectional Studies ; Fibronectins* ; Humans ; Inflammation ; Joints ; Knee ; Osteoarthritis ; Rheumatoid Factor ; Synovial Fluid