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HelpTest Code BRAZR Brazil Nut, IgE with Reflex to Brazil Nut Component, IgE, Serum
Ordering 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: 0.6 mL
Collection Instructions: Centrifuge and aliquot serum into a plastic vial.
Useful For
Evaluation of patients with suspected Brazil nut allergy
Reflex Tests
| Test ID | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| BRAZX | Brazil Nut Component, IgE, S | No | No |
Testing Algorithm
Testing begins with analysis of Brazil nut-specific total IgE. If the Brazil nut-specific total IgE result is negative (<0.10 kU/L), testing is complete.
If the Brazil nut-specific total IgE result is 0.10 kU/L or more, then the Brazil nut component (Ber e 1) test will be performed at an additional charge.
Special Instructions
Method Name
Fluorescent Enzyme Immunoassay (FEIA)
Reporting Name
Brazil Nut Component Reflex, SSpecimen Type
SerumSpecimen Minimum Volume
0.4 mL
Specimen Stability Information
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Serum | Refrigerated (preferred) | 14 days | |
| Frozen | 90 days |
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 |
Concentrations of 0.70 kU/L or more (class 2 and above) will flag as abnormally high.
Reference values apply to all ages.
Interpretation
When detectable total Brazil nut IgE antibody is present (≥0.10 IgE kUa/L), additional specific component IgE antibody testing will be performed. If a potential specific allergenic Brazil nut component IgE is detectable (≥0.10 IgE kUa/L), an interpretive report will be provided.
When the sample is negative for total Brazil nut IgE antibody (<0.10 IgE kUa/L), further testing for specific Brazil nut component IgE antibodies will not be performed. A negative IgE result for total Brazil nut antibody may indicate a lack of sensitization to the potential Brazil nut allergenic component.
Clinical Reference
1. Salo PM, Arbes SJ Jr, Jaramillo R, et al. Prevalence of allergic sensitization in the United States: results from the National Health and Nutrition Examination Survey (NHANES) 2005-2006. J Allergy Clin Immunol. 2014;134(2):350-359. doi:10.1016/j.jaci.2013.12.1071
2. Waserman S, Watson W. Food allergy. Allergy Asthma Clin Immuno. 2011;7 Suppl 1(Suppl 1):S7
3. Abrams EM, Sicherer SH. Diagnosis and management of food allergy. CMAJ. 2016;188(15):1087-1093
4. Weinberger T, Sicherer S. Current perspectives on tree nut allergy: a review. J Asthma Allergy. 2018;11:41-51
5. Lomas JM, Jarvinen KM. Managing nut-induced anaphylaxis: challenges and solutions. J Asthma Allergy. 2015; 8:115-123
6. Maloney J, et al. The use of serum-specific IgE measurements for the diagnosis of peanut, tree nut, and seed allergy. J Allergy Clin Immunol. 2008;122(1):145-51
7. Sicherer SH, Burks AW, Sampson HA. Clinical features of acute allergic reactions to peanut and tree nuts in children. Pediatrics. 1998;102(1):e6
8. Crespo JF, James JM. Fernandez C, Rodriguez J. Food allergy: Nuts and tree nuts. Br J Nutr. 2006;96 Suppl 2:S95-102
9. Yang L, Clements S, Joks R. A retrospective study of peanut and tree nut allergy: Sensitization and correlations with clinical manifestations. [published online ahead of print, 2015 Feb 27]. Allergy Rhinol (Providence). 2015;doi:10.2500/ar.20105.6.0108
10. Masthoff L, Hoff R, Verhoeckx KC, et al. A systematic review of the effect of thermal processing on the allergenicity of tree nuts. Allergy. 2013;3;68(8):983-993
11. Borja JM, Bartolome B, Gomez E, Galindo PA, Feo F. Anaphylaxis from Brazil nut. Allergy. 1999;54(9):1007-1008
12. Mazokopakis EE, Liontiris MI. Commentary: Health concerns of Brazil nut consumption. J Altern Complement Med. 2018;24(1):3-6
13.McWilliam V, Koplin J, Lodge C, Tang M, Dharmage S, Allen K. The prevalence of tree nut allergy: A systematic review. Curr Allergy Asthma Rep. 2015;15(9):54.
14.Rayes H, Raza AA, Williams A, Matthews S, Arshad SH. Specific IgE to recombinant protein (Ber e 1) for the diagnosis of Brazil nut allergy. Clin Exp Allergy. 2016;46(4):654-656.
15.Pastorello EA, Farioli L, Pravettoni V, Ispano M, Conti A, Ansaloni R, et al. Sensitization to the major allergen of Brazil nut is correlated with the clinical expression of allergy. J Allergy Clin Immunol. 1998;102(6 Pt 1):1021-1027.
16. Moreno FJ, Clemente A. 2S Albumin storage proteins: What makes them food allergens? Open Biochem J. 2008;2:16-28
Day(s) Performed
Monday through Friday
Report Available
Same day/1 to 3 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
This test has been cleared, approved, or is exempt by the US Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.CPT Code Information
86003
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| BRAZR | Brazil Nut Component Reflex, S | 6050-9 |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| BRAZ1 | Brazil Nut, IgE, S | 6050-9 |
Forms
If not ordering electronically, complete, print, and send an Allergen Test Request (T236) with the specimen.