Laboratory Test DirectoryShare
Rheumatoid Factor (RF), IgG
Rheumatoid factor sensitivity in rheumatoid arthritis varies from 30% in population-based studies to 70-80% in hospital-based studies, where the disease tends to be more severe. Higher titers of RF are more specific for the diagnosis of rheumatoid arthritis (RA) and are more common in patients with rapidly progressive joint destruction.
Immune complexes formed in solution scatter light in proportion to their size, shape, and concentration. Turbidimeters measure the reduction of incidence light due to reflection, absorption, or scatter.
An 8 to 12-hour fast is recommended
Collect: Serum Separator Tube (SST) - 0.5 ml
Stability: Rheumatoid Factor is stable in serum for 1 day stored at 20-25°C, 8 days stored at 2 - 8°C, and 3 months stored at <-20°C.
At Accu Reference: Refrigerated -7 days: Frozen- 1 month
NOTE: * This test is approved for all states. *
Accu Reference Medical Laboratory
|Cross Reference:||Rheumatoid factor|
Adults: < 14 IU/mL
Reportable Range is from 10 to 120 IU/L. Samples exceeding the upper limit of linearity are diluted and repeated.