What is rheumatoid factor or RF test?

What is rheumatoid factor or RF?
Rheumatoid factor are autoantibodies of IgM type immunoglobulins that are created in the immune system of the individual. These antibodies are in the normal state for physical defense against infections, but in inflammatory diseases, such as rheumatoid arthritis, or rheumatoid arthritis, cause joint pains. These autoantibodies cause abnormalities with a wrong attack on the body's natural tissues.

This test is performed to determine the presence of such antibodies in the individual's body, which is the best indicator of the evaluation of the individual immune system's performance.

Body appearance symptoms can not be a proper measure for the diagnosis of this rheumatoid factor in the body. On the other hand, joint pain symptoms are not always reliable for the diagnosis of rheumatoid arthritis. Because individuals with this rheumatoid factor may be afflicted with other connective tissue diseases such as Raynaud's disease, scleroderma, autoimmune disorders, systemic lupus erythematosus, Sjögren's syndrome, or people with other chronic infectious diseases such as viral hepatitis.

When is rheumatoid factor testing recommended?
A rheumatoid factor test may be done when a person has signs and symptoms of rheumatoid arthritis. These symptoms may include:

Pain, warmth, swelling and morning eyelids in the joints
Touch the nodules or subcutaneous nodes
If the disease progresses concurrently with the RF test, other tests, such as X-ray imaging, are prescribed for examination of swollen joint capsules and loss of cartilage and bone tissue.
An RF test may be repeated again after the first test is negative and the symptoms continue to occur.

Interpretation of the results of the RF test
The results of this experiment are often reported as a headline. In the headline, the ratio of less than 1:80 or less than 60 RF units per ml of blood is reported as normal or normal. RF testing should be interpreted along with the results of other tests and clinical symptoms.

Rheumatoid factor is found in 70 to 90% of patients with rheumatoid arthritis, although not diagnosed in some cases. In people who experience severe signs and symptoms of rheumatism, significant concentrations of RF can be found in laboratory samples that enhance the risk of rheumatoid arthritis. The higher levels of rheumatoid factor have a direct relationship with the severity of the disease.

The negative result of the RF test does not rule out the presence of rheumatoid arthritis. About 20% of people with rheumatoid arthritis have levels much lower than RF detection. In such cases, the CCP antibody test may be positive and used to confirm the rheumatoid arthritis.

Several studies have shown that in patients treated with some disease-changing factors, they can lower blood levels of RF in the blood. Other tests, such as the ESR, or the same sedation rate of red blood cells and the CRP (C-reactive protein), can be used to monitor more precisely the disease.

Some health problems raise the level of RF, but they can not be diagnosed with only this protein in the blood. As:

Viral and parasitic infections
Chronic lung and liver disease
There is no specific preparation for this experiment.

You can simply use the membership in Trita and enter the user's area of ​​the smart doctor system, you will also be able to record the test in Trita and interpret the amount in your test without the need for a physician. Please check the blood tests section after you arrive.

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  1. https://labtestsonline.org/tests/rheumatoid-factor-rf
  2. https://www.healthline.com/health/rheumatoid-factor-rf#results


Fatemeh Ghorbani

Fatemeh Ghorbani

فاطمه قربانی هستم، لیسانس ژنتیک، به علوم نوین پزشکی و ایمونولوژی علاقمندم. از شما دوست گرامی بخاطر مطالعه این مقاله و همچنین مجموعه تریتا بخاطر فرصت انتشار مطالبم در راستای کمک به ارتقای دانش کمال تشکر دارم. شاد باشید و سلامت

my name is Fatemeh Ghorbani, I have a B.S in genetics and interested in immunology and medical science. I believe that, even into the smallest acts, should be put our heart, mind and soul. Thank you for reading my article