Experts in Medical & Radiologic Imaging
RADIOLOGY
SECOND OPINION
Medical Conditions
Factor, Rheumatoid
Antibodies directed against antigenic determinants, i.e., Gm (gamma chain), in the Fc region of IMMUNOGLOBULIN G, found in the serum of about 80% of patients with classical or definite rheumatoid arthritis, but in only about 20% of patients with juvenile rheumatoid arthritis. Rheumatoid factors may be IMMUNOGLOBULIN M, IMMUNOGLOBULIN G, or IMMUNOGLOBULIN A antibodies, although other serological tests measure only IMMUNOGLOBULIN M. Rheumatoid factors also occur in other connective tissue diseases and infectious diseases. (From Dorland, 28th ed)
