Rheumatoid Factor, IgA by EIA (RDL)
Use
EIA methods have the added advantage of being able to simultaneously detect RF of IgG and IgA subclasses in addition to RF IgM and are not susceptible to prozone. It has become apparent that the specificity and predictive value of the RF test is substantially increased by the detection of all three RF isotypes.
Special Instructions
For accurate testing, ensure serum is separated from cells within one hour of collection and transferred to a transport tube before freezing.
Limitations
The EIA method may detect RF of the IgA isotype effectively, but results should be interpreted in conjunction with clinical findings and other laboratory assessments. Prozone effect susceptibility is minimized. False negatives or positives may occur based on analytical and biological variability.
Methodology
Immunoassay (ELISA)
Biomarkers
LOINC Codes
- 33313-8
- 33313-8
Result Turnaround Time
5-7 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.3 mL
Container
Plastic transport tube
Collection Instructions
Separate serum from cells within one hour. Transfer to a plastic transport tube before freezing.
Storage Instructions
Store frozen or refrigerated.
Causes for Rejection
Grossly hemolyzed; bacterial contamination; lipemic, icteric, non-serum specimen types
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 7 days |
| Refrigerated | 14 days |
| Frozen | 60 days |
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