Rheumatoid Factor
Label Mnemonic: RF
Epic code: LAB206
Downtime form: A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery
Chemistry
6240 RCP
356-3527
Specimen(s):
Plasma
Collection Medium:
Plasma Separator Tube 4.5 mL
Alternate Collection Media:
Call laboratory for additional acceptable specimen collection containers.
Minimum:
3 mL; whole blood in light green top tube or ONE Microtainer®.
Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around Time:
1 hour (upon receipt in laboratory)
Reference Range:
<14 IU/mL
Test Limitations:
Criterion: Recovery within plus or minus 10% of initial value.

Icterus: No significant interference up to an I index of 60.

Hemolysis: No significant interference up to an H index of 300 
(approximate hemoglobin concentration: 300 mg/dL).

Lipemia (Intralipid): No significant interference up to an L index of 
2000.

There is poor correlation between turbidity and triglycerides 
concentration.

No high-dose hook effect up to RF activities of 6000 IU/mL.

Drugs: No interference was found at therapeutic concentrations using 
common drug panels.

Reference:
Glick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences 
in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-474.
Methodology:
Immunoturbidimetric Assay
CPT Code:
86431