Rheumatoid factor test (RF): goal, results, levels

A rheumatoid factor test (RF) detects the rheumatoid factor, a type of antibody (proteins that fight on harmful substances) in your blood. RF antibodies sometimes attack healthy cells and tissues, leading to autoimmune conditions.

Rheumatoid factors are commonly used to diagnose rheumatoid arthritis, but can also detect other conditions, such as Sjögren syndrome, lupus, hepatitis C, tuberculosis and even certain cancers.

Health care providers can recommend an RF test if you have symptoms such as joint pain, swelling of joints, fatigue, low fever and unexplained weight loss.

A rheumatoid factor test can detect the presence of rheumatoid factor, an antibody that can mistakenly attack cells and healthy tissues. The body can produce RF following an abnormal immune reaction. Having RF in your blood does not always indicate an autoimmune disease, but its presence is a potential sign.

The RF test most often helps to diagnose rheumatoid arthritis (RA). PR symptoms usually start in one or two sides of the wrist, hand or feet joints. A health care provider may suggest an RF test if you have common PR symptoms, in particular:

• Sensitivity and swelling in the joint
• Joint pain
• Stiffness
• Fatigue
• Fever
• Weight loss

Health care providers can also recommend the RF test to diagnose other autoimmune conditions and infections associated with high levels of rheumatoid factor. These conditions include:

• Sjögren syndrome
• Juvenile idiopathic arthritis (JIA)
• Systemic lupus erythematosus (Lide)
• Tuberculosis
• Hepatitis 100

The blood test can also help detect certain types of cancer, including leukemia and lung cancer.

You don’t need special preparation for the rheumatoid factor test. However, check with your health care provider to see if you have other tests that require fasting before the appointment. You should also ask yourself if you can continue to take your medication or supplements before the test.

The RF test generally takes place in a diagnostic laboratory or the office of your supplier. Wear comfortable and cowardly clothes that allow easy access to your arm when it is time to take blood. You can consider bringing a family member or a friend on the day of the test if the blood tests make you anxious.

If you have insurance, talk to your insurer to see if they will cover the cost of the test or if you will have to pay your pocket.

The rheumatoid factor test is to pull a small blood sample from a vein in your arm. The supplier making the blood sample will generally use a vein inside the elbow, although he can use one on the back of your hand. The process usually takes less than five minutes.

During the test

During the test, you will sit on a chair during a Phlebotomist (A health professional formed to take blood) uses a needle to gain blood in a vein in your arm. Here is what the supplier will do during a blood sample:

1. Clean the area with antiseptics
2. Put an elastic band on the upper arm to exert pressure on the area
3. Insert the needle into a vein and recover blood in a bottle or a tight -stricken tube attached to the needle
4. Remove the needle and band from your arm
5. Put a cotton or bandage on the Aiguille site

You can feel a little bite when the needle enters and spells, but these symptoms disappear quickly.

After the test

You can go home almost immediately after the test and resume your daily activities. If you tend to feel weak and dizzy after blood tests, it may be better to ask someone to bring you home. Your health professional may ask you not to lift heavy objects for 24 hours after the test, as he can put pressure on the needle site.

Blood tests are generally quite safe. You may experience slight pain or bruises on the needle site, but these symptoms disappear quickly.

There may be rare complications, in particular bleeding, infection on the needle site or nervous lesions. It is important to contact your health care provider if these complications arise.

The results of a rheumatoid factor test are generally available in a few hours to a few days depending on the test. Some laboratories have an online portal where you can check the results. You may need to visit your health care provider to discuss the results and determine if you need additional tests.

Interpret your results

The results of the rheumatoid factor will be listed in international units by Millilitre or as a title. A title is a measure of the concentration of a substance in a solution and is displayed as a report.

The normal rheumatoid factor in the blood is generally less than 15 international units per milliliter or a title of 1 to 80. The normal beach may vary slightly depending on different laboratories.

A higher beach than normal indicates a positive result, while a beach lower than normal suggests a negative result.

Positive

A positive result means that you have a higher level than normal rheumatoid factor in your blood. This can be a sign of rheumatoid arthritis, other autoimmune diseases or an underlying infection.

Your health professional may recommend additional tests to confirm what causes the positive RF test. These include:

• C-reactive protein test
• Erythrocyte Stimulation rate test (ESR)
• Peptide Citrulliné anticyclic Antibody test (anti-CCP)
• Anuclear antibody test (ANA)

Negative result

A negative result means that you have little or no rheumatoid factor in your blood. However, this does not exclude the presence of rheumatoid arthritis or other conditions. In some cases, people with PR have no high levels of rheumatoid factor in their blood.

If you have low RF levels in your blood but you still have joint pain or other symptoms, talk to your health care provider additional tests.

The rheumatoid factor test measures the levels of RF antibodies in your blood. It can help diagnose conditions such as rheumatoid arthritis and Sjögren syndrome.

A health care provider can control an RF blood test if you have symptoms such as swelling of joints, joint pain and fatigue.

High RF levels may indicate that you have a condition that requires additional diagnostic tests.