IgE Peanut
Peanut (f13)
Test Codes
EPIC: LAB2111622, SOFT: EPNU, Antrim #31388
Department
Immunology
Specimen Collection Criteria
Collect: One Gold-top SST tube.
Twenty individual allergen assays or allergen screens can be performed on one 5 mL Gold-top SST tube. Each allergen assay requires 100 mcL of serum.
Physician Office/Draw Specimen Preparation
Let specimen clot 30-60 minutes then immediately centrifuge to separate serum from cells. Refrigerate (2-8°C or 36-46°F) the centrifuged collection tube within two hours of collection.
Preparation for Courier Transport
Transport: Centrifuged collection tube, refrigerated (2-8°C or 36-46°F).
Rejection Criteria
- Plasma specimens.
- Severely lipemic or hemolyzed specimens.
In-Lab Processing
Let specimen clot 30-60 minutes then immediately centrifuge to separate serum from cells. Room temperature is acceptable for a maximum of two hours.
Storage
Specimen Stability for Testing:
Centrifuged SST Tubes and Microtainers® with Separator Gel
Room Temperature (20-26°C or 68-78.8°F): 2 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): Unacceptable
Red-top Tubes and Microtainers® without Separator Gel
Room Temperature (20-26°C or 68-78.8°F): 2 hours
Refrigerated (2-8°C or 36-46°F): Unacceptable
Frozen (-20°C/-4°F or below): Unacceptable
Serum Specimens (Pour-Overs)
Room Temperature (20-26°C or 68-78.8°F): 2 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): 1 month
Specimen Storage in Department Prior to Disposal:
Refrigerated (2-8°C or 36-46°F): 7 days
Laboratory
Royal Oak Special Chemistry Laboratory
Performed
Monday – Friday.
Results available the next business day.
Reference Range
Allergy Reference Range: Less than 0.35 kU/L.
Range (kU/L) |
Class |
Interpretation |
Less than or equal to 0.34 |
0 |
Negative |
0.35-0.69 |
1 |
Low |
0.70-3.49 |
2 |
Medium |
3.50-17.49 |
3 |
High |
17.50-49.99 |
4 |
Very High |
50.0-100.0 |
5 |
Very High |
Greater than 100 |
6 |
Very High |
Test Methodology
Fluorescence Enzyme Immunoassay (FEIA).
Interpretation
The allergen class may not be predictive of clinical disease in some patients. The diagnosis of allergy should be based upon patient history and clinical findings. The diagnosis of allergy should not be based upon laboratory findings alone.
Clinical Utility
Positive assay results indicate a high probability of allergic disease. Negative assay results effectively rule out allergy induced by those allergens.
Clinical Disease
Hypersensitivity to peanuts is relatively common and peanut allergies are one of the most common sources of food-caused anaphylactic death in the United States (1). Three percent of the American population is thought to have peanut allergies. Thirty percent of patients with food allergies are sensitive to peanuts. These patients lose their sensitivity to peanut allergens (1). Peanut-allergic individuals typically cannot tolerate other legumes such as peas, beans, and licorice. Symptoms may include nausea, vomiting, hives, angioedema, labored breathing, and/or anaphylactic shock.
When exposed to the peanut protein the patient's T-cells are unable to produce gamma interferon, which is important in inhibiting the synthesis of IgE. Peanut allergens are typically heat stable. Therefore, cooking or roasting peanuts will not abrogate their allergen potential. The primary allergen of peanuts is designated "Peanut-I" (2).
Certain factors such as alcohol consumption and exercise enhance the reactivity to a food allergen in sensitized individuals. Individuals with food allergies usually have other allergies as well, including allergies to pollen or dust.
Reference
- Sachs MI and Yunginger JW, "Food-Induced Anaphylaxis." in "Food Allergy," Immunology and Allergy Clinics of North America: 11:4, 743-000, 1991.
- Metcalfe, Dean D. M.D., Hugh A. Sampson, M.D., Ronald A. Simon, M.D., Food Allergy: Adverse Reactions to Foods and Food Additives. Blackwell Scientific Publications: Boston, 1991, pg. 40-42, 155, 345.
CPT Codes
86003
LOINC: 6206-7
Contacts
Special Chemistry Laboratory – RO
248-551-8071
Name: Special Chemistry Laboratory – RO
Location:
Phone: 248-551-8071
Last Updated
11/11/2024
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