A rheumatoid factor test is meant to detect the patient’s rheumatoid factor levels. RF is an autoantibody made within the immune system. It is different from normal antibodies in that while the latter attack pathogens such as viruses and bacteria, RF sometimes attacks healthy cells within the body. Testing for RF is mostly done alongside other lab tests in case the patient is suspected to be suffering from Sjögren syndrome or rheumatoid arthritis.
The Purpose Of The Test
An RF test is intended to find out if the patient has RF present in their blood, often in order to detect rheumatology diseases. Some healthy people too have evident amounts of RF. That said, the presence of RF can be indicative of some underlying health condition that warrants additional testing, to make sure the person does not have an autoimmune disorder.
- Diagnosing autoimmune disorders: If a person shows signs of arthritis and rheumatology-related disorders that fall under the autoimmune category, diagnostic testing is appropriate. Doctors may recommend getting an RF test if the person has multiple inflamed joints.
- Figuring out disease severity: RF testing is able to give doctors an idea about how severe the patient’s rheumatoid arthritis is. If there’s a high level of RF then the case is severe, and the disease is likely affecting parts of the body other than the joints. This includes the blood vessels and the lungs.
Despite rheumatoid arthritis treatment being able to lower the RF in the blood, repeated RF testing is not employed to check patients during treatment.
What The Test Measures
RF testing, as mentioned already, checks the amount of RF present in the blood. There are many ways to do this, one of them being the antibody titer test. This test is able to detect how much of any specific antibody type there is in the blood.
Experts have yet to understand well how RF develops and affects the body. Most researchers are of the opinion that it may occur as a result of the body responding to pathogens such as bacteria or viruses, as well as to other triggers which may be confusing to the immune system.
When You Should Get RF Testing Done
Doctors generally recommend RF tests in events where the patient experiences rheumatoid arthritis symptoms, and the latter can include the following.
- Morning stiffness lasting 30 minutes or longer
- Joint symptoms such as pain and swelling
- Intermittent fever
- Tiredness or fatigue
- Weight loss
- Appetite loss
- Dry eyes, mouth, etc.
Bear in mind that RF testing does not take the place of a screening test for diagnosing rheumatoid arthritis in people who do not have symptoms. Patients who test RF positive but aren’t experiencing symptoms generally do not develop rheumatoid arthritis.