At a Glance
Why Get Tested?
To help in the diagnosis of rheumatoid arthritis (RA) and differentiate it from other types of arthritis; sometimes to help evaluate the prognosis of a patient with RA
When to Get Tested?
If a patient has joint inflammation and/or undiagnosed or undifferentiated inflammatory polyarthritis (symptoms may suggest but do not yet meet the criteria of RA) and the doctor suspects RA
A blood sample taken from a vein in your arm
The Test Sample
What is being tested?
The cyclic citrullinated peptide antibody (CCP) test is a relatively new assay that detects the presence of anti-citrulline antibodies in the blood. Citrulline is an unusual amino acid (protein building block), which is created when the amino acid arginine is altered. There is speculation that conversion of arginine to citrulline resulting in “citrullinated” proteins in the lining of joints, may be the target of anti-CCP antibodies in RA, which may contribute to inflammatory process in RA.
How is the sample collected for testing?
A blood sample is obtained by inserting a needle into a vein in the arm.
NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.
Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.
Ask a Laboratory Scientist
NOTE: This article is based on research that utilizes the sources cited here as well as the collective experience of the Lab Tests Online Editorial Review Board. This article is periodically reviewed by the Editorial Board and may be updated as a result of the review. Any new sources cited will be added to the list and distinguished from the original sources used.