Quick Review Cards for Medical Laboratory Science

Serological Tests for Rheumatoid

Arthritis (RA)

Immunology Review 413

TEST

Rheumatoid factor (RF)

Anti–cyclic citrullinated
peptide antibody (Anti-CCP)

COMMON METHOD(S)

Agglutination, ELISA,

nephelometry

ELISA

COMMENTS

Autoantibody (usually IgM) against IgG. Pos in 70%–80% of patients

with RA. Not specific for RA. Present with other autoimmune diseases,

infections, & in some normal individuals. Agglutination tests only detect

IgM RF. ELISA & nephelometry can also detect IgA & IgG classes of RF.

Automated methods more common.

More specific for RA than RF. Associated with more severe form of RA.