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HelpTest 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 |
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.
Clinical Reference
1. Cross M, Smith E, Hoy D, et al. The global burden of rheumatoid arthritis: estimates from the global burden of disease 2010 study. Ann Rheum Dis. 2014;73:1316-1322
2. Aletaha D, Neogi T, Silman AJ, et al. 2010 Rheumatoid arthritis classification criteria: an American College of Rheumatology/European League Against Rheumatism collaborative initiative. Arthritis Rheum. 2010;62:2569-2581
3. Schellekens GA, Visser H, de Jong BA, et al. The diagnostic properties of rheumatoid arthritis antibodies recognizing a cyclic citrullinated peptide. Arthritis Rheum. 2000;43:155-163
4. Derksen VFAM, Huizinga TWJ, van der Woude D. The role of autoantibodies in the pathophysiology of rheumatoid arthritis. Semin Immunopathol. 2017;39:437-446
5. Sieghart D, Platzer A, Studenic P, et al. Determination of autoantibody isotypes increases the sensitivity of serodiagnostics in rheumatoid arthritis. Front Immunol. 2018;9:876
6. Brink M, Hansson M, Mathsson-Alm L, et al. Rheumatoid factor isotypes in relation to antibodies against citrullinated peptides and carbamylated proteins before the onset of rheumatoid arthritis. Arthritis Res Ther. 2016;18:43
7. Kelmenson LB, Wagner BD, McNair BK, et al. Timing of Elevations of Autoantibody Isotypes Prior to Diagnosis of Rheumatoid Arthritis. Arthritis Rheumatol. 2020;72:251-261
8. Oka S, Higuchi T, Furukawa H, et al. Serum rheumatoid factor IgA, anti-citrullinated peptide antibodies with secretory components, and anti-carbamylated protein antibodies associate with interstitial lung disease in rheumatoid arthritis. BMC Musculoskelet Disord. 2022;23:46
9. Van Hoovels L, Vander Cruyssen B, Sieghart D, et al. IgA rheumatoid factor in rheumatoid arthritis. Clin Chem Lab Med. 2022;60:1617-1626
10. Van Hoovels L, Vander Cruyssen B, Sieghart D, et al. Multicentre study to improve clinical interpretation of rheumatoid factor and anti-citrullinated protein/peptide antibodies test results. RMD Open. 2022;8:e002099
Day(s) Performed
Wednesday
Report Available
2 to 7 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test 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 |