Rheumatoid factor concentration reported in IU/mL. immunoglobulins and are members of a class of proteins that become elevated in inflammatory states. RA is most sensitive for monitoring the level of inflammation associated with rheumatoid arthritis.
Rheumatoid factor is used as a blood test for the diagnosis of rheumatoid arthritis. Rheumatoid factor is present in about 80% of adults (but a much lower proportion of children) with rheumatoid arthritis.
The “normal” range (or negative test result) for rheumatoid factor is less than 14 IU/ml. Any result with values 14 IU/ml or above is considered abnormally high, elevated, or positive.
