Order Code: 4418
ABN Requirement: No
Synonyms: RF; Rheumatoid Arthritis; RA Factor
Specimen: Serum
Volume: 1.0 mL
Minimum Volume: 0.5 mL
Container: Gel-barrier tube (SST, Tiger Top)
Collection:
- Collect and label sample according to standard protocols.
- Gently invert tube 5 times immediately after draw. DO NOT SHAKE.
- Allow blood to clot 30 minutes.
- Centrifuge for 10 minutes.
Transport: Store serum at 2°C to 8°C after collection and ship the same day per packaging instructions included with the provided shipping box
Stability:
Ambient (15-25°C): 5 days
Refrigerated (2-8°C): 7 days
Frozen (-20°C): 90 days
Causes for Rejection: Specimens other than serum; improper labeling; samples not stored properly; samples older than stability limits
Methodology: Immunoturbidimetric Assay
Turn Around Time: 3-4 days
Reference Range:
| Age | IU/mL |
| All Ages | <14 |
Clinical Significance: Elevated RF is found in collagen vascular diseases such as SLE, rheumatoid arthritis, scleroderma, Sjögren’s syndrome, and in other conditions such as leprosy, tuberculosis, syphilis, malignancy, thyroid disease, and in a significant percentage of otherwise normal elderly patients.
The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.