Rheumatoid Factor

immunohematologyImmunity & InflammationBlood

Rheumatoid factor (RF) is a type of antibody. The immune system makes rheumatoid factor by mistake, or when it is overactive.

Why it matters: A rheumatoid factor test measures how much rheumatoid factor is in the blood, and can help a provider rule certain issues out or narrow in on a diagnosis. A high rheumatoid factor can mean an autoimmune disease or another health condition is present, but the test does not diagnose anything directly, and an elevated result does not automatically mean rheumatoid arthritis. Some people have high RF levels and never experience any symptoms.

Source · Cleveland Clinic — what it is, why it matters, related conditions

Reference Range
0.0 – 14.0IU/mL
0
14LowNormalHigh
Associated Conditions
An autoimmune disease or another health condition, which a high rheumatoid factor can mean
Related Markers
hs-CRPCRPESR
Common questions

What is Rheumatoid Factor?

Rheumatoid factor (RF) is a type of antibody. The immune system makes rheumatoid factor by mistake, or when it is overactive.

What might a high or low Rheumatoid Factor mean?

A rheumatoid factor test measures how much rheumatoid factor is in the blood, and can help a provider rule certain issues out or narrow in on a diagnosis. A high rheumatoid factor can mean an autoimmune disease or another health condition is present, but the test does not diagnose anything directly, and an elevated result does not automatically mean rheumatoid arthritis. Some people have high RF levels and never experience any symptoms.

What is the typical reference range for Rheumatoid Factor?

The general-population reference range shown here is 0 – 14 IU/mL. Reference ranges describe the general population and are not a personal target — discuss your results with your physician.

More in immunohematology
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