Rheumatoid factor is an antibody
that is measurable in the blood. This test is part of the arthritis
panel because rheumatoid factor is not usually present in a normal
individual. It is commonly used for the diagnosis of Rheumatoid
arthritis. Almost 80% of adults with rheumatoid arthritis have
the presence of rheumatoid factor. This percentage is much lower
among children with juvenile
rheumatoid arthritis.
The rheumatoid factor antibody attaches to a substance in the body
called immunoglobulin G (IgG), thus forming a molecule known as
an immune complex. The immune complex can activate various inflammatory
processes in the body.
