Autoimmune diseases cause the body to attack itself, which leads to inflammation and results in damage to muscles, tissues, and organs. The inflammation produces antibodies in the blood that can be measured and the levels used to diagnose specific autoimmune diseases. Rheumatoid arthritis causes increased amounts of immunoglobulins within the joint fluid, which the body sees as foreign, causing inflammation and producing antibodies which results in joint destruction. Other parts of the body can also be affected: heart, blood vessels, nerves, and lungs. RF measures the amount of antibodies in the blood.
Highest RF blood levels are seen in people with rheumatoid arthritis, lower levels are seen in people with SLE (systemic lupus erythmatosis), Sjogren's syndrome, or scleroderma. High RF levels are also seen in people with chronic infection from a virus, heart infection that has not yet shown any symptoms, TB, liver or kidney disease, mononucleosis, syphilis, or leukemia. There can be false negative results with this test, and the elderly can also have false positives.
In a medical emergency, step away from this web site and call for emergency help. Remember, we're not doctors and we don't claim to be able to diagnose your condition. The information and services we provide or display here are merely intended to make you a more knowledgeable patient so that you can have smarter conversations with your actual health care providers.