blood test range for rheumatoid arthritis
When this antibody attaches to healthy body tissue, it can create damage. The RF test is not perfect for determining if you have rheumatoid arthritis. While 80 percent of people with RA display this factor, 20 percent donât (Weinblatt, 2000).And 10 percent of people without rheumatoid arthritis test positive for RF due to hepatitis, leukemia, lupus, or other disorders (Weinblatt, 2000). rheumatoid factor. 2  The lab will check for rheumatoid factor (RF) antibodies that collect in the synovium of the joint. 3  These antibodies are present in about 80 percent of RA patients. 4  erythrocyte sedimentation rate (ESR) and C-reactive protein.