Rheumatoid Factor (RF)
Immunity & allergy markersWhat the test generally measures, and what to ask about it.
Longetic keeps every lab and record you’ve had organized and easy to find, so your own Rheumatoid Factor (RF) values sit together on one chart and you walk into your next appointment prepared.
What is Rheumatoid Factor (RF)?
A blood test for an antibody that can target your own antibodies, used mainly as part of looking into rheumatoid arthritis.
Rheumatoid factor is an antibody that, instead of fighting germs, can target the body's own antibodies, and this test measures how much of it is in your blood. It is used mostly together with other tests to help investigate rheumatoid arthritis when joint symptoms are present, and higher levels can also be associated with other autoimmune conditions, some chronic infections, and occasionally certain cancers. It is not a clean yes/no answer: some healthy people have small amounts, and some people with rheumatoid arthritis have little or none, so it is rare to get tested for high RF levels if you do not have symptoms, and results are always read alongside symptoms and other findings.
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References
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