Biomarker: F217-IgE Brussel Sprouts

Overview

F217-IgE measures immunoglobulin E antibodies in blood that recognize Brussels sprouts (Brassica oleracea var. gemmifera). IgE is an antibody involved in immediate hypersensitivity reactions, including food-allergic responses. A detectable or elevated result indicates sensitization to Brussels sprouts but does not, by itself, confirm a clinical food allergy or predict reaction severity. The test is clinically useful as part of an allergy evaluation guided by the patient’s exposure history and symptoms; an allergist may use a medically supervised oral food challenge when confirmation is needed.

Clinical Use Cases

Supporting evaluation of suspected IgE-mediated reactions after eating Brussels sprouts.
Assessing sensitization to Brussels sprouts in patients with a compatible history of food-allergic symptoms.
Contributing to differential evaluation of symptoms such as urticaria, angioedema, oral itching, wheezing, vomiting, or anaphylaxis after food exposure.
Investigating possible cross-sensitization among related vegetables in the Brassicaceae family, although a positive result must be interpreted clinically.
Supporting, but not replacing, clinical history, physical examination, skin-prick testing, and medically supervised oral food challenge when indicated.

Specimen Types

Venous blood.
Serum is the typical specimen for quantitative allergen-specific IgE measurement.
Some assay platforms may accept plasma, such as EDTA or heparinized plasma, according to the laboratory’s validated instructions.

Measurement Methods

In-vitro allergen-specific IgE immunoassay using a Brussels-sprout extract or allergen preparation.
Fluorescent enzyme immunoassay, including solid-phase assays such as ImmunoCAP.
Enzyme-linked immunosorbent assay-based methods.
Chemiluminescent immunoassays.
Immunoblot or multiplex allergen immunoassay methods may be used in some laboratories.

Test Preparation and Influencing Factors

Fasting is generally not required for serum-specific IgE testing.
Antihistamines generally do not interfere with serum IgE measurements, unlike skin-prick testing. Medication changes should be discussed with the treating clinician.
The test should be ordered when the clinical history suggests a possible reaction to Brussels sprouts or a related food; broad, non-targeted testing can identify sensitization without clinically relevant allergy.
Recent exposure to Brussels sprouts is generally not required before blood collection.
Results may be affected by the assay platform, allergen extract, calibration system, and laboratory reference intervals.
A positive result indicates sensitization, not necessarily symptomatic allergy. The concentration does not reliably predict the severity of a future reaction.
A negative result reduces the likelihood of IgE sensitization but should be interpreted with the clinical history.
Do not discontinue prescribed medication or intentionally consume a suspected allergen for testing purposes without medical guidance.