Beta-Lactoglobulin, IgE, Serum
Use
This test is useful for establishing a diagnosis of an allergy to beta-lactoglobulin. It helps in defining the allergen responsible for eliciting signs and symptoms and in identifying allergens that are responsible for allergic responses and/or anaphylactic episodes. Additionally, it is used to confirm sensitization prior to beginning immunotherapy and to investigate the specificity of allergic reactions to insect venom allergens, drugs, or chemical allergens. However, testing for IgE antibodies is not useful in patients previously treated with immunotherapy to determine if residual clinical sensitivity exists or in patients in whom the medical management does not depend upon the identification of allergen specificity.
Special Instructions
For a listing of allergens available for testing, refer to the provided checklist or contact the laboratory. If not ordering electronically, complete, print, and send the Allergen Test Request form (T236) with the specimen. The collection instructions highlight the necessity to centrifuge and aliquot serum into a plastic vial for optimal specimen integrity.
Limitations
Some individuals with clinically insignificant sensitivity to allergens may have measurable levels of IgE antibodies in serum, necessitating test result interpretation in the broader clinical context. False-positive results for IgE antibodies can also occur in patients with markedly elevated serum IgE levels (>2500 kU/L) due to nonspecific binding to allergen solid phases. Therefore, results must be interpreted with caution, especially in such cases.
FDA ApprovedNew York Approved
Methodology
Immunoassay (FEIA)
Biomarkers
LOINC Codes
- 11177-3
- 11177-3
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
For 1 allergen: 0.3 mL For more than 1 allergen: (0.05 mL x number of allergens) + 0.25 mL deadspace
Container
Preferred: Serum gel Acceptable: Red top Submission: Plastic vial
Collection Instructions
Centrifuge and aliquot serum into a plastic vial.
Storage Instructions
Refrigerated: 14 days Frozen: 90 days
Causes for Rejection
Gross hemolysis: OK Gross lipemia: OK
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 14 days |
| Frozen | 90 days |