Synonyms

   Citrullinated Antibody

Clinical Significance

   It is useful for : Evaluating patients suspected of having rheumatoid arthritis (RA), Differentiating RA from other inflammatory arthritis or connective tissue diseases.

Specimen

   Serum

Stability

   Refrigerated (preferred) : 21 days

   Frozen : 21 days

   Ambient : 7 days

Reference Range

   < 17 U/ml

Interpretation

   A positive result for cyclic citrullinated peptide (CCP) antibodies may be suggestive of rheumatoid arthritis (RA) if compatible clinical features of disease are present. Significantly elevated levels of CCP antibodies may be useful to identify RA patients with erosive joint disease.

Limitation

   Positive results for cyclic citrullinated peptide (CCP) antibodies may occur in some patients with systemic lupus erythematosus or other autoimmune, connective tissue diseases. In a Mayo Clinic study (see Interpretation), the false-positive rate in this subgroup was approximately 10%.