Test ID BLWRF Walnut-Food, IgE, with Reflex to Walnut-Food Components, IgE, Serum
Ordering Guidance
For a listing of allergens available for testing, see Allergens - Immunoglobulin E (IgE) Antibodies.
Specimen Required
Collection Container/Tube:
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Useful For
Evaluation of patients with suspected walnut-food allergy
Reflex Tests
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
BLWX | Walnut-Food Components, IgE, S | No | No |
Testing Algorithm
Testing begins with analysis of walnut-food-specific total IgE. If walnut-food-specific total IgE result is negative (<0.10 kU/L), testing is complete.
If walnut-food-specific total IgE result is 0.10 kU/L or more, then walnut-food component (Jug r 1 and Jug r 3) testing will be performed at an additional charge.
Special Instructions
Method Name
Fluorescent Enzyme Immunoassay (FEIA)
Reporting Name
Walnut-Food Component Reflex, SSpecimen Type
SerumSpecimen Minimum Volume
0.6 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 14 days | |
Frozen | 90 days |
Reference Values
Class |
IgE kU/L |
Interpretation |
0 |
<0.10 |
Negative |
0/1 |
0.10-0.34 |
Borderline/Equivocal |
1 |
0.35-0.69 |
Equivocal |
2 |
0.70-3.49 |
Positive |
3 |
3.50-17.4 |
Positive |
4 |
17.5-49.9 |
Strongly positive |
5 |
50.0-99.9 |
Strongly positive |
6 |
≥100 |
Strongly positive |
Concentrations of 0.70 kU/L or more (class 2 and above) will flag as abnormally high.
Reference values apply to all ages.
Day(s) Performed
Monday through Friday
Report Available
Same day/1 to 3 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
86003
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
BLWRF | Walnut-Food Component Reflex, S | 6273-7 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
BLW1 | Walnut-Food, IgE, S | 6273-7 |
Forms
If not ordering electronically, complete, print, and send an Allergen Test Request (T236) with the specimen.