Rheumatoid arthritis blood tests look for antibodies like rheumatoid factor and anti-CCP and also test for levels of inflammation to help reach a diagnosis. To diagnose rheumatoid arthritis there is no one test that can on its own reach a diagnosis. Rheumatoid factor arthritis, there are a number of criteria that must be established in order to reach a rheumatoid arthritis diagnosis.
As part of the criteria for diagnosing rheumatoid arthritis, doctors will order multiple blood tests. These blood tests look for specific indicators that support the possibility that the patient could have rheumatoid arthritis. None of these tests can singularly conclude that a patient has rheumatoid arthritis. It’s an antibody that attacks healthy tissue and leads to joint inflammation potentially resulting in the development of rheumatoid arthritis symptoms. A rheumatoid factor blood test determines the level of rheumatoid factor in a patient’s blood. Once the rheumatoid factor level reaches a certain range, the patient tests positive for rheumatoid factor. Years ago, doctors used the positive result of rheumatoid factor in a patient’s blood to firmly diagnose them with rheumatoid arthritis.
If a patient showed signs of joint inflammation and tested positive for rheumatoid factor, then rheumatoid arthritis generally became the clear diagnosis. Since then, research has shown us that many people contain the rheumatoid factor antibody in their blood but that it can lead to different autoimmune or inflammatory conditions besides rheumatoid arthritis. This now makes the test considered less conclusive than it used to be. This discovery blurred the lines about what does and doesn’t constitute a rheumatoid arthritis diagnosis. Today, doctors are more cautious about diagnosing a patient with rheumatoid arthritis if they test positive for rheumatoid factor. Although, it can still be a strong indicator in many patient cases. After the research came forward about the fact that non-rheumatoid arthritis patients can have rheumatoid factor in their blood, doctors started testing for another antibody, the anti-cyclic citrullinated protein.
The anti-CCP antibody is another antibody that leads to inflammatory symptoms that cause rheumatoid arthritis. Often the anti-CCP antibody will be found in patients’ blood anywhere from 5 to 10 years before they ever exhibit symptoms of rheumatoid arthritis. The presence of anti-CCP and rheumatoid factor in a patient’s blood provides a strong case for making a rheumatoid arthritis diagnosis, provided the patient’s symptoms are also clearly consistent with rheumatoid arthritis. Doctors can actually measure the level of inflammation a patient is experiencing in order to help reach a rheumatoid arthritis diagnosis. In the ESR test, the technician takes a sample of blood and adds it into a tube.
The test measures the rate at which the red blood cells fall and settle in the bottom of the tube. The rate is measured in millimetres per hour. A fast sedimentation rate indicates there is inflammation in the body. This is because inflammation causes the red blood cells to clump together, become denser, and fall faster causing them to settle more quickly. The ESR test is not used on its own to diagnose rheumatoid arthritis. It is just a helpful tool in allowing doctors to have a complete idea of what is happening with the patient.