Test Details
Methodology
Enzyme-linked immunosorbent assay (ELISA)
Result Turnaround Time
5 - 7 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.
Test Includes
This test is a component of Rheumatoid Factor Isotypes, IgG, IgA and IgM by EIA.
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.
Specimen Requirements
Specimen
Serum
Volume
1 mL
Minimum Volume
0.3 mL (Note: This volume does not allow for repeat testing.)
Collection Instructions
Separate serum from cells within one hour. Transfer to a plastic transport tube before freezing.
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 7 days |
Refrigerated | 14 days |
Frozen | 60 days |
Freeze/thaw cycles | Stable x1 |
Storage Instructions
Store frozen or refrigerated.
Causes for Rejection
Grossly hemolyzed; bacterial contamination; lipemic, icteric, non-serum specimen types
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 520101 | RF, IgA by EIA (RDL) | 33313-8 | 520102 | RF, IgA by EIA (RDL) | U | 33313-8 |
| Order Code | 520101 | |||||
| Order Code Name | RF, IgA by EIA (RDL) | |||||
| Order Loinc | 33313-8 | |||||
| Result Code | 520102 | |||||
| Result Code Name | RF, IgA by EIA (RDL) | |||||
| UofM | U | |||||
| Result LOINC | 33313-8 |