Test Code GRW Giant Ragweed, IgE, Serum
Reporting Name
Giant Ragweed, IgEUseful For
Establishing a diagnosis of an allergy to giant ragweed
Defining the allergen responsible for eliciting signs and symptoms
Identifying allergens:
-Responsible for allergic response and/or anaphylactic episode
-To confirm sensitization prior to beginning immunotherapy
-To investigate the specificity of allergic reactions to insect venom allergens, drugs, or chemical allergens
Performing Laboratory
Mayo Clinic Laboratories in RochesterSpecimen Type
SerumOrdering 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: 0.5 mL for every 5 allergens requested
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Specimen Minimum Volume
For 1 allergen: 0.3 mL
For more than 1 allergen: (0.05 mL x number of allergens) + 0.25 mL deadspace
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 14 days | |
Frozen | 90 days |
Special Instructions
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 |
Reference values apply to all ages.
Day(s) Performed
Monday through Friday
CPT Code Information
86003
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
GRW | Giant Ragweed, IgE | 6124-2 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
GRW | Giant Ragweed, IgE | 6124-2 |
Interpretation
Detection of IgE antibodies in serum (class 1 or greater) indicates an increased likelihood of allergic disease as opposed to other etiologies and defines the allergens that may be responsible for eliciting signs and symptoms.
The level of IgE antibodies in serum varies directly with the concentration of IgE antibodies expressed as a class score or kU/L.
Report Available
Same day/1 to 3 daysReject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Method Name
Fluorescence Enzyme Immunoassay (FEIA)
Forms
If not ordering electronically, complete, print, and send an Allergen Test Request (T236) with the specimen.