Video Q & A:

Symptoms, Tests, & Diagnosis


Which lab tests diagnose rheumatoid arthritis?

Expert:   Kenya Beard , ACNP-BC, Hunter College »

Before you get an official RA diagnosis, you'll have to undergo a blood test. Watch this video to learn what the doctor is looking for.

Transcript: In addition to a PHYSICAL evaluation, a rheumatoid arthritis diagnosis may involve several blood tests. The MAIN test is called a rheumatoid factor test. Rheumatoid factor, or RF, is an antibody that collects in the joint lining of a person with rheumatoid arthritis. Someone with RA has HIGH concentrations of RF in their blood. In about 80 percent of RA patients, a blood test will reveal a HIGH RF factor. A HIGH RF factor is less common at the start of the rheumatoid arthritis, and it can increase as the disease develops. About TWENTY percent of people with rheumatoid arthritis will PERSISTENTLY test negative for rheumatoid factor. This doesn’t mean they DON’T have the disease—they will often display all the traditional symptoms such as joint pain, morning stiffness and swelling. Other blood tests, such as an anti-CCP test, may assist healthcare providers in diagnosis when a person has a negative RF test. The anti-CCP test checks your blood for the amount of another antibody called cyclic citrullinated peptides. It’s often used to evaluate patients whose symptoms don’t yet meet the criteria for RA. High levels are found in about 60 to 70 percent of people with RA. The results of an anti-CCP test can indicate whether or not RA will become severe. Measures of inflammation are often higher in people with rheumatoid arthritis. There are two tests to check for it—the C-reactive protein test and the erythrocyte sedimentation rate test, also called an ESR or sed rate test. These are more often used to indicate how severe your RA is, not to IDENTIFY it. Finally, a healthcare provider may check your IRON levels--mild anemia is present in about 25 to 35 percent of patients with RA. If you are diagnosed with RA, your healthcare provider will put you on medication that can slow the progress of your disease. Rheumatoid arthritis is manageable if you stick to your treatment. More »

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