Rheumatoid Factor, Serum
Use
Rheumatoid factors (RF) are a heterogeneous group of autoantibodies associated with the diagnosis of rheumatoid arthritis (RA) and can also be found in other inflammatory rheumatic and nonrheumatic conditions as well as in some healthy individuals aged 60 years and older. Despite being nonspecific, the detection of RF or anti-citrullinated protein (anti-CCP) antibody is part of the 2010 diagnosis criterion of the American College of Rheumatology for classification of RA. RF is most useful when utilized alongside anti-CCP testing, particularly for diagnosis and prognosis of rheumatoid arthritis.
Special Instructions
An alternative or complementary assay to rheumatoid factor (RF) that has demonstrated utility in the diagnosis and assessment of rheumatoid arthritis (RA) is CCP / Cyclic Citrullinated Peptide Antibodies, IgG, Serum. Utilization of both tests can provide clinical value in the diagnosis of RA.
Limitations
The titer of RF correlates poorly with disease activity, but those patients with high titers tend to have more severe disease and a poorer prognosis than seronegative patients. Nonrheumatoid and rheumatoid arthritis (RA) populations are not clearly separate with regard to the presence of rheumatoid factor (RF). RF factor antibodies may be present in non-affected individuals, particularly in patients aged 60 years or older, and in various nonrheumatoid diseases characterized by chronic inflammation.
FDA ApprovedNew York Approved
Methodology
Immunoassay (Turbidimetry)
Biomarkers
LOINC Codes
- 11572-5
- 11572-5
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.75 mL
Container
Plastic vial
Collection Instructions
Centrifuge and aliquot serum into a plastic vial.
Causes for Rejection
Gross hemolysis
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 14 days |
| Frozen | 14 days |