False Ragweed, IgE, Serum
Use
The test is useful for establishing a diagnosis of an allergy to false ragweed, defining the allergen responsible for eliciting signs and symptoms, identifying allergens responsible for allergic response and/or anaphylactic episode, confirming sensitization prior to beginning immunotherapy, and investigating the specificity of allergic reactions to insect venom allergens, drugs, or chemical allergens. It identifies IgE antibodies associated with allergic diseases and provides insights into the immune response to specific allergens.
Special Instructions
The test is not useful in patients previously treated with immunotherapy to determine if residual clinical sensitivity exists, or in patients where the medical management does not depend upon identification of allergen specificity. If not ordering electronically, complete, print, and send an Allergen Test Request (T236) with the specimen.
Limitations
Some individuals with clinically insignificant sensitivity to allergens may have measurable levels of IgE antibodies in serum. False-positive results for IgE antibodies may occur in patients with markedly elevated serum IgE (>2500 kU/L) due to nonspecific binding to allergen solid phases. Test results must be interpreted in the clinical context as identifying IgE antibodies indicates allergic disease likelihood but must be considered alongside other clinical findings.
FDA ApprovedNew York Approved
Methodology
Immunoassay (FEIA)
Biomarkers
LOINC Codes
- 6115-0
- 6115-0
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
Container
Serum gel; Acceptable: Red top; Submission Container: Plastic vial
Collection Instructions
Centrifuge and aliquot serum into a plastic vial.
Causes for Rejection
Gross hemolysis: OK; Gross lipemia: OK
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 14 days |
| Frozen | 90 days |