JOINT HEALTH
Although there is no single blood test that can confirm the diagnosis of an inflammatory arthritis such as rheumatoid arthritis, there are laboratory tests that can help screen for some of these conditions.
In general, these blood tests look for specific proteins produced by the immune system as well as markers of inflammation associated with such conditions.
Although there are many tests available, there are several common blood tests that your doctor may order if he/she suspects you might be experiencing signs and symptoms suggestive of an inflammatory arthritis.
1. Erythrocyte Sedimentation Rate (ESR or sed rate)
This is a simple blood test that helps to show how much inflammation is in the body. However, this test does not show exactly where in the body the inflammation is nor what is causing it. A high ESR indicates high levels of inflammation, and a low ESR indicates low levels of inflammation.
2. C- Reactive Protein (CRP)
CRP is another blood test that indicates the presence of inflammation in the body. Along with the ESR, the CRP is used to help determine how much inflammation is present in order to help access disease activity as well as help guide medical therapy.
3. Rheumatoid Factor (RF)
RF is a blood test that measures the levels of certain proteins produced by the immune system that attack normal cells and tissues. It is possible to have rheumatoid arthritis without the presence of a RF. It is also possible to have the presence of a RF without having rheumatoid arthritis.
4. Cyclic Citrillinated Peptide (CCP) antibodies
Like RF, CCP are proteins produced by the immune system that attack normal cells and tissues. CCP is more specific for rheumatoid arthritis than RF and its presence suggests a potentially more severe disease course.
5. Antinuclear Antibody Test (ANA)
This blood test can be used to help diagnose and determine the type of autoimmune disorder affecting you. ANA is an autoantibody produced which is commonly seen in lupus. However, many autoimmune diseases are associated with a positive ANA test, such as Sjogren’s Syndrome, Scleroderma, psoriatic arthritis, and polymyositis/dermatomyositis. It is also seen in about 10% of normal individuals, and these levels increase with age. There are several more specific autoantibodies that your doctor may order to follow up with a positive result.
6. Complete Blood Count (CBC)
A CBC consists of 3 different cell lines that make up the blood; white blood cells, red blood cells and platelets. In many inflammation disorders, such as rheumatoid arthritis and lupus, the body is not able to make and regulate these cell types. A CBC is often ordered along with these other screening tests.
Autoimmune diseases are often complex and difficult to diagnosis. Early treatment by a rheumatologist is important to help ensure the best possible positive outcome. If you are experiencing joint pain, stiffness or swelling, tell your doctor. After a full assessment of your signs and symptoms, a thorough physical examination, and imaging tests, these simple labs tests may be ordered to help properly diagnosis an inflammatory arthritis. Once this is done, your doctor will help choose the best treatment options for you.
