Synonyms
- 14-3-3
- 14-3-3 η Protein
- ACPA
- Anti-CCP
- Anticitrullinated Protein Antibody
- Augurex
- CCP
- eta
- IdentRA
- RF
- RF Titer
- Rheumatoid Factor
Expected Turnaround Time
8 - 12 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Related Information
Related Documents
For more information, please view the literature below.
Rheumatoid Arthritis Testing With Better Performance Brochure
Specimen Requirements
Specimen
Serum
Volume
2 mL
Minimum Volume
0.8 mL
Container
Red-top or gel-barrier tube
Storage Instructions
Frozen preferred, refrigerate acceptable
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 3 days |
Refrigerated | 3 days |
Frozen | 14 days |
Freeze/thaw cycles | Stable x3 |
Test Details
Use
Aid in the diagnosis of rheumatoid arthritis (RA)1,2
Limitations
Results of this panel should be used in conjunction with clinical findings and other laboratory tests.
"It is acknowledged that an individual patient may meet the definition of RA without requiring that all tests be performed. For example, patients with a sufficient number of joints involved and longer duration of symptoms will meet criteria regardless of their serologic or acute-phase response status. The classification criteria can be applied to any patient or otherwise healthy individual, as long as 2 mandatory requirements are met: First, there must be evidence of currently active clinical synovitis (i.e., swelling) in at least 1 joint as determined by an expert assessor. Second, the criteria may be applied only to those patients in whom the observed synovitis is not better explained by another diagnosis."6
Methodology
RA Factor: Immunoturbidimetry
CCP Antibodies: ELISA
14-3-3 eta protein: ELISA
Reference Interval
• RA Factor:<14 IU/mL
• CCP Antibodies IgG, IgA: Units
Negative: <20
Weak positive: 20 - 39
Moderate positive: 40 - 59
Strong positive: >59
• 14-3-3 eta protein: <0.2 ng/mL
Additional Information
This RheumAssure panel is comprised of three tests: RA Factor, CCP Antibodies, and 14-3-3 eta protein.
Used together, these three markers are able to diagnose established RA with a sensitivity of 88-96% and early RA with a sensitivity of 78- 92%.1,2
RA factor (also called RF) is elevated in established RA (sensitivity 72-85%)2,3 and in early RA (sensitivity 44-63%).1,4 Its specificity for RA is 80%.3
CCP Antibodies have similar sensitivities for established RA (66-79%) and early RA (59%)2,3 but higher specificity (90-96%).3,5
Serum 14-3-3 eta protein is elevated in both established RA (sensitivity 77%) and early RA (sensitivity 59-64%).1,2 It may provide a 15-20% incremental benefit in identifying early RA.1,4
Therefore, elevation of one or more markers of RheumAssure is consistent with a diagnosis of rheumatoid arthritis. When all three markers are negative, an RA diagnosis is less likely.
Footnotes
1. Maksymowych WP, Boire G, van Schaardenburg D, et al. 14-3-3η Autoantibodies: Diagnostic Use in Early Rheumatoid Arthritis. J Rheumatol 2015;42(9):1587-1594.26178283
2. Maksymowych WP, Naides SJ, Bykerk V, et al. Serum 14-3-3η is a novel marker that complements current serological measurements to enhance detection of patients with rheumatoid arthritis. J Rheumatol 2014;41(11):2104-2113.25128504
3. Lee DM, Schur PH. Clinical utility of the anti-CCP assay in patients with rheumatic diseases. Ann Rheum Dis 2003 Sep;62(9):870-874.12922961
4. Carrier N, Marotta A, de-Brum-Fernandes AJ, et al. Serum levels of 14-3-3η protein supplement C-reactive protein and rheumatoid arthritis-associated antibodies to predict clinical and radiographic outcomes in a prospective cohort of patients with recent-onset inflammatory polyarthritis. Arthritis Res Ther 2016 Feb 1;18:37.26832367
5. Dubucquoi S, Solau-Gervais E, Lefranc D, et al. Evaluation of anti-citrullinated filaggrin antibodies as hallmarks for the diagnosis of rheumatic diseases. Ann Rheum Dis 2004 Apr;63(4):415-419.15020336
6. American College of Rheumatology. The 2010 ACR-EULAR Classification Criteria for Rheumatoid Arthritis. http://www.rheumatology.org/practice/clinical/classification/ra/ra_2010.asp. Accessed June 20, 2014.
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 504509 | RheumAssure | 504560 | Rheumatoid Arthritis Factor | Units/mL | 11572-5 | |
| 504509 | RheumAssure | 504554 | CCP Antibodies IgG/IgA | Units | 57093-7 | |
| 504509 | RheumAssure | 504551 | 14.3.3 ETA, Rheum. Arthritis | ng/mL | 75880-5 |
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