Western Ragweed, IgE, Serum
Use
The test is useful for establishing a diagnosis of an allergy to Western ragweed and defining the allergen responsible for symptoms. It helps identify allergens responsible for allergic responses or anaphylactic episodes and can confirm sensitization prior to beginning immunotherapy. However, testing for IgE antibodies is not useful for patients treated with immunotherapy to determine residual sensitivity, or when medical management doesn't require allergen specificity.
Special Instructions
If not ordering electronically, complete and send an Allergen Test Request form (T236) with the specimen. For a list of available allergens, refer to the Allergens - Immunoglobulin E (IgE) Antibodies PDF document.
Limitations
The test may produce measurable levels of IgE antibodies even in individuals with clinically insignificant sensitivity to allergens. False-positives can occur due to nonspecific binding in patients with extremely high serum IgE levels (>2500 kU/L). Results must be interpreted in conjunction with clinical context, as some individuals with allergy may not show significant IgE levels.
New York Approved
Methodology
Immunoassay (FEIA)
Biomarkers
LOINC Codes
- 6275-2
- 6275-2
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.5 mL for every 5 allergens requested
Minimum Volume
0.3 mL for 1 allergen
Container
Preferred: Serum gel; Acceptable: Red top; Submission: Plastic vial
Collection Instructions
Centrifuge and aliquot serum into a plastic vial.
Causes for Rejection
Gross hemolysis and lipemia are acceptable.
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 14 days |
| Frozen | 90 days |