What is a CCP antibody test?

This test looks for CCP (cyclic citrullinated peptide) antibodies in your blood. CCP antibodies, also called anti-CCP antibodies, are a type of antibody called autoantibodies. Antibodies and autoantibodies are proteins made by the immune system:

• Antibodies protect you from disease by fighting foreign substances like viruses and bacteria.
• Autoantibodies like CCP antibodies are abnormal proteins. Instead of protecting your body, they attack your body's healthy cells by mistake.

CCP antibodies target healthy tissues in the joints. Joints are places in your body where two bones meet, such as your elbows, wrists, and knees. If CCP antibodies are found in your blood, it can be a sign of rheumatoid arthritis. Rheumatoid arthritis is an autoimmune disease that gets worse over time. It causes pain, swelling, stiffness, and a loss of function in your joints.

CCP antibodies are found in most people who have rheumatoid arthritis. They are almost never found in people who don't have the disease.

Other names: Cyclic citrullinated peptide antibody, anticitrullinated peptide antibody, citrulline antibody, anti-cyclic citrullinated peptide, anti-CCP antibody, ACPA

What is it used for?

A CCP antibody test is used to help diagnose or rule out rheumatoid arthritis.

It's often done along with or after a rheumatoid factor (RF) test. Rheumatoid factors are another type of autoantibody. RF tests used to be the main test to help diagnose rheumatoid arthritis. However, RF factors can be found in people with other autoimmune diseases and even in some healthy people. And some people with RA have little to no RF factors. Doing both tests provides a more accurate diagnosis than only using RF testing results.

Why do I need a CCP antibody test?

You may need this test if you have symptoms of rheumatoid arthritis. These include:

• Joint pain
• Joint stiffness, especially in the morning
• Joint swelling
• Fatigue
• Low-grade fever

You may also need this test if other tests couldn't confirm or rule out a diagnosis of rheumatoid arthritis.

What happens during a CCP antibody test?

A health care professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.

Will I need to do anything to prepare for the test?

Be sure to tell your provider about all medicines, vitamins, and dietary supplements you are taking. You may need to stop taking certain substances for 8 hours before your test.

Are there any risks to the test?

There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.

What do the results mean?

If your CCP antibody results were positive, it means these antibodies were found in your blood. A negative result means no CCP antibodies were found. The meaning of these results may depend on the results of a rheumatoid factor (RF) test as well as a physical exam.

If you have symptoms of rheumatoid arthritis, and your results show:

• Positive CCP antibodies and positive RF, it means that you probably have rheumatoid arthritis.
• Positive CCP antibodies and negative RF, it could mean you are in the early stages of rheumatoid arthritis or will develop it in the future.
• Negative CCP antibodies and negative RF, it means you are less likely to have rheumatoid arthritis. Your provider may need to do more tests to help find out what is causing your symptoms.

Sometimes, CCP antibodies may be found in other conditions such as:

• Other autoimmune disorders such as Sjogren's syndrome or lupus
• Active tuberculosis (TB)
• Chronic lung disease

To understand the results of a CCP antibody test, your provider will consider your symptoms, medical history, physical exam, and the results of other tests.

Learn more about laboratory tests, reference ranges, and understanding results.

Is there anything else I need to know about a CCP antibody test?

Rheumatoid arthritis can be difficult to diagnose, especially in its early stages. Your provider may order one or more tests in addition to CCP antibody and RF tests. These include x-rays of your joints and the following blood tests:

• Erythrocyte sedimentation rate (ESR)
• Synovial fluid analysis
• C-reactive protein
• Antinuclear antibody

These blood tests can show increased protein in the blood, which may be a sign of having a medical condition that causes inflammation. Inflammation can be a symptom of rheumatoid arthritis.