Rheumatoid Factor (RF)

Department of Immunology

Notes

• RF can be used as a bio marker for Rheumatoid Arthritis (RA) but is not diagnostic and can also be seen in up to 10% of the normal population. Most patients with RA have detectable RF, but up to 30% are negative.
• Other autoimmune diseases, such as Systemic Lupus Erythematosus , Mixed Connective Tissue Disease and Sjögren's Syndrome, may also cause a positive RF.

Sample Requirements

Adult

5ml Gold-top SST tube

Paediatric

1ml Serum Sample

Turnaround Times

7 days

Reference Ranges

0-14 IU/ml

Assay Interferences

Lipaemic, haemolysed or icteric samples should be avoided.