Rheumatoid factor

Keywords: RF

Specimen:

5 mL blood in plain tube.

Method:

Nephelometry; turbidimetry. Agglutination of gamma globulin-coated latex particles or erythrocytes.

Reference Interval:

< 30 IU/L.

Application:

Diagnosis and prognosis of Rheumatoid arthritis.

Also positive in other chronic inflammatory conditions and immune complex diseases.

Interpretation:

Patients with rheumatoid arthritis and positive rheumatoid factor tend to have more aggressive articular disease and are at greater risk of extra-articular complications.

Reference:

Newkirk MM. J Rheumatol 2002; 29(10): 2034-2040.