Test Code RFPN Rheumatoid Factor Panel, Serum
Additional Testing Requirements
Rheumatoid factor (RF) IgA and RF IgM should be tested in combination with CCP / Cyclic Citrullinated Peptide Antibodies, IgG, Serum; or following positive or equivocal results for either RHUT / Rheumatoid Factor, Serum; or RAPAN / Rheumatoid Arthritis Panel, Serum.
Specimen Required
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container: Plastic vial
Specimen Volume: 1 mL
Collection Instructions: Centrifuge and aliquot serum into plastic vial.
Useful For
Evaluating patients at-risk of rheumatoid arthritis (RA) or features of inflammatory arthritis
Differentiating the antibody isotype profile in patients positive for rheumatoid factor (RF)
Aid in the risk stratification of RF-seropositive patients with RA
Profile Information
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
RFA | Rheumatoid Factor IgA, S | No | Yes |
RFM | Rheumatoid Factor IgM, S | No | Yes |
Method Name
Chemiluminescent Immunoassay
Reporting Name
Rheumatoid Factor Panel, SSpecimen Type
SerumSpecimen Minimum Volume
0.3 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 14 days | |
Frozen | 28 days | ||
Ambient | 48 hours |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | Reject |
Heat-treated specimens | Reject |
Reference Values
RHEUMATOID FACTOR, IgA
Negative: <20 CU
Positive: ≥20 CU
Reference values apply to all ages.
RHEUMATOID FACTOR, IgM
Negative: <5.0 IU/mL
Positive: ≥5.0 IU/mL
Reference values apply to all ages.
Interpretation
The presence of rheumatoid factor (RF) IgM or IgA at abnormal levels in association with anti-citrullinated peptide/protein antibodies has high specificity for a diagnosis of rheumatoid arthritis (RA). However, the presence of RF isotypes in any combination may be found in a variety of conditions, including Sjogren syndrome and hepatitis infections.
Day(s) Performed
Wednesday
Report Available
2 to 7 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
86431 x2
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
RFPN | Rheumatoid Factor Panel, S | 106053-2 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
RFM | Rheumatoid Factor IgM, S | 9338-5 |
RFA | Rheumatoid Factor IgA, S | 33313-8 |