ARUP's Laboratory Test Directory

0051298: Rheumatoid Factor, IgM, IgG, & IgA by EIA

Test Mnemonic: RF PAN
Methodology: Enzyme Immunoassay

Performed: Tue

Reported: 1-8 days

Specimen Required:  
Collect: One 4 mL SST.

Transport: 1 mL serum at 2-8°C. (Min: 0.5 mL)

Pediatric Collection/Transport: 0.5 mL serum at 2-8°C.

Remarks: Do not freeze.

Unacceptable Conditions: Hemolyzed, lipemic, contaminated, or frozen specimens.

Stability: After separation from cells: Ambient: 2 days; Refrigerated: 2 weeks; Frozen: Unacceptable

Reference Interval:
 
Test Number Components Reference Interval
 Rheumatoid Factor, IgG by EIA Less than 21 U/mL
 Rheumatoid Factor, IgM by EIA Less than 26 IU/mL
 Rheumatoid Factor, IgA by EIA Less than 36 U/mL

Interpretive Data:
The presence of abnormal levels of all three RF isotypes has a specificity of 99% for RA.  However, RF in any isotype combination may be found in hepatitis C, Sjögren's syndrome and other chronic infections.



CPT Code(s):
86430 x2 RF IgG/IgA; 86431 RF IgM

 

 

 
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