Ann Rheum Dis 62:870-874 doi:10.1136/ard.62.9.870
  • Extended report

Clinical utility of the anti-CCP assay in patients with rheumatic diseases

  1. D M Lee,
  2. P H Schur
  1. Department of Medicine, Division of Rheumatology, Immunology and Allergy Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA.
  1. Correspondence to:
    Professor P H Schur, Brigham and Women’s Hospital, Rheumatology and Immunology, 75 Francis Street, PBB-2, Boston, MA 02115, USA;
  • Accepted 22 January 2003


Objectives: To determine the frequency of antibodies to cyclic citrullinated peptides (CCP) in a group of patients with a diversity of rheumatic diseases.

Methods: 249 consecutive sera from an arthritis clinic sent for rheumatology testing were selected for testing with the anti-CCP2 assays and for the presence of rheumatoid factor (RF). Patient charts were reviewed for demographic information, clinical diagnosis, radiographic information, and other laboratory data.

Results: The sensitivity and specificity of anti-CCP reactivity for the diagnosis of rheumatoid arthritis (RA) were 66.0% and 90.4%, respectively. This compared with the sensitivity and specificity of RF for RA at 71.6% and 80.3%. Furthermore, 10/29 (34%) RF− patients with RA demonstrated reactivity to CCP. The presence of either anti-CCP or RF increased testing sensitivity for diagnosis of RA to 81.4%; the presence of both RF and anti-CCP demonstrated a testing specificity similar to that of anti-CCP reactivity alone for the diagnosis of RA (91.1%).

Conclusions: The detection of anti-CCP is useful for the diagnosis of RA, in fact even more so than RF, because of its higher specificity.