Doctors may order a cyclic citrullinated peptide (CCP) antibody test and other exams to confirm or rule out a rheumatoid arthritis (RA) diagnosis.
A positive CCP antibody test doesn’t necessarily mean you have RA. However, it can be an important marker, especially if you also test positive for rheumatoid factor (RF).
A CCP antibody test is a diagnostic blood test that helps doctors confirm or rule out RA. It involves drawing a blood sample from a vein in your arm with a small needle, which experts then analyze in a laboratory.
You may feel a slight sting at the needle site during the test, but it typically isn’t painful. You don’t need to fast before your test, and no particular preparation is necessary.
A doctor may order the CCP antibody test when another RA blood test is positive or when your symptoms may show RA.
The test measures levels of CCP antibodies in your blood. These antibodies are also called anti-CCP antibodies.
Antibodies are proteins your immune system produces to target and destroy foreign or potentially harmful substances.
If a blood test shows high amounts of an antibody, it means your immune system is protecting you from something. In some instances, like in RA, your immune system produces antibodies that try to destroy healthy tissue.
RA is an autoimmune condition, which means your immune system’s antibodies identify internal tissues or substances as foreign and try to destroy them, even though they aren’t harmful.
CCP antibodies commonly appear in your bloodstream when you have RA. They target joint tissue, which eventually causes joint symptoms like:
- swelling
- heat
- discoloration
- pain
Antibodies are sometimes present in blood for
Some people with RA don’t have detectable CCP antibodies in their blood. If you have RA symptoms but test negative for CCP and RF (another type of RA-related antibody), a doctor may give you a seronegative RA diagnosis.
People who test positive for CCP and RF tests may have
A positive result means you have a high count of CCP antibodies in your blood, while a negative result means you don’t. These results may not say much on their own.
A doctor won’t diagnose RA solely based on a positive CCP test result. They may, however, decide to run other tests, like the RF.
Here’s a look at what the results of these two tests together may suggest:
CCP test Result | RF test result | Likely meaning |
---|---|---|
positive CCP | positive RF | RA is a strong possibility, especially if you have symptoms. |
positive CCP | negative RF | RA in its early stages is possible, or you may have a high risk of developing it. |
negative CCP | negative RF | If you have symptoms, you may have seronegative RA. A doctor may still order additional tests to determine whether symptoms have a different cause. If you don’t have symptoms, you likely don’t have RA. |
Some people without RA or other autoimmune diseases can have CCP antibodies in their blood. For example, about
Biotin and CCP testing
Taking high doses of biotin before your CCP test could produce a false-negative result. Some experts recommend waiting at least 8 hours after consuming 5 to 10 milligrams of biotin before you go in for a blood test. You’re only likely to consume this much biotin if you take supplements.
If you’re taking biotin supplements, telling the doctor and the lab in advance is a good idea.
Doctors primarily use a CCP test to diagnose RA, but CCP antibodies could also be present in people with other conditions, such as:
- Sj?gren disease
- polymyalgia rheumatica
- lupus
- chronic lung disease
- active tuberculosis
- some forms of cancer
If a doctor thinks that you have RA, they may want to do additional examinations and tests, including:
- a review of your personal and family medical history
- a physical exam
- imaging tests of your joints, such as:
- other types of blood tests like:
- RF test
- anti-nuclear antibody test, which helps doctors find antibodies often in people with
advanced RA disease - complete blood count
- inflammation tests like erythrocyte sedimentation rate and C-reactive protein
Learn more about RA diagnosis.
Testing positive for a CCP test shows that you may have RA or be at risk of developing it in the future. Usually, more tests are necessary to confirm or rule out this diagnosis.