CCP

Does this test have other names?

Anticyclic citrullinated peptide, CCP antibodies, anti-CCP, anticitrullinated peptide antibodies (ACPA), cyclic citrullinated peptide antibody

What is this test?

This blood test checks for an amino acid called citrulline. Citrulline is present when you have rheumatoid arthritis (RA).

RA occurs when your immune system attacks normal cells in your joints. Citrulline is a byproduct of joint damage. In response, your body often makes antibodies against citrulline. These antibodies are called anticyclic citrullinated peptide (anti-CCP) antibodies.

Why do you need this test?

You may need this test if your doctor is trying to find out whether you have RA.

Even in the early stages of the disease, the CCP test can give your doctor a clear idea of how quickly your symptoms may get worse. The results can also help your doctor figure out the treatment you will need.

This test is also a good choice if other tests for RA don't show definite results.

What other tests might you have along with this test?

Your doctor may order other tests for RA. The most common are joint X-rays or scans and blood tests to check your level of rheumatoid factor. But doctors are beginning to use the CCP test more often because it is more specific for RA than other tests.

What do your test results mean?

Test results may vary depending on your age, sex, health history, and other things. Your test results may be different depending on the lab used. They may not mean you have a problem. Ask your doctor what your test results mean for you.

In general, testing positive for anti-CCP antibodies along with symptoms may mean that you have RA.

But a positive result might also mean you have:

• Another autoimmune rheumatic disease, such as lupus or Sjögren syndrome.

• Tuberculosis.

• Chronic lung disease.

How is this test done?

The test is done with a blood sample. A needle is used to draw blood from a vein in your arm or hand. 

Does this test pose any risks?

Having a blood test with a needle carries some risks. These include bleeding, infection, bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may feel a slight sting or pain. Afterward, the site may be sore. 

What might affect your test results?

Other factors aren't likely to affect your results. 

How do you get ready for this test?

You don't need to prepare for this test. Be sure your doctor knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illegal drugs you may use.