RF, IgM by EIA (RDL) is a laboratory test that measures rheumatoid factor (RF) of the IgM class using enzyme immunoassay (EIA) methodology. RF is an autoantibody that targets the Fc region of IgG antibodies and is commonly associated with autoimmune conditions, particularly rheumatoid arthritis (RA). Elevated RF IgM levels can indicate inflammatory or autoimmune diseases, including Sjogren’s syndrome, systemic lupus erythematosus (SLE), and other connective tissue disorders. However, RF can also be detected in some healthy individuals or those with chronic infections, making it important to interpret results alongside clinical symptoms and other diagnostic markers. The RDL designation refers to the reference diagnostic laboratory performing the test, ensuring standardized measurement and reliability.
RF, IgM by EIA (RDL)
Every lab result you’ve ever had, charted and explained.
Healthmatters is a tracker for your lab results. Upload a report from any lab, any country — every marker charted and explained.
Start with my report →
All our content is backed by peer-reviewed studies, academic research, and trusted medical sources. We’re committed to accuracy and transparency — see our editorial policy for details.