Biomarker: G017-IgE Bahia Grass

Overview

G017-IgE Bahia Grass measures serum immunoglobulin E (IgE) antibodies directed against Bahia grass pollen, Paspalum notatum. Bahia grass pollen can trigger IgE-mediated allergic rhinitis and asthma in sensitized individuals. A high result indicates sensitization to Bahia grass pollen, while a low or undetectable result makes sensitization less likely but does not exclude allergy. The result is clinically useful for identifying potential grass-pollen triggers when interpreted with seasonal symptoms, exposure history, and physical findings because specific IgE demonstrates sensitization rather than clinical allergy by itself.

Clinical Use Cases

Supports evaluation of seasonal allergic rhinitis, conjunctivitis, or asthma associated with grass-pollen exposure.
Helps identify Bahia grass as a potential aeroallergen in patients with compatible symptoms.
Assists with selecting relevant allergens for environmental avoidance counseling or allergen immunotherapy evaluation.
Helps assess patients whose clinical history suggests Bahia grass allergy but who cannot undergo skin-prick testing because of skin disease, medication use, or other limitations.
Supports research on grass-pollen sensitization, allergen cross-reactivity, and seasonal respiratory disease.
May be useful when testing for Bahia grass specifically because Bahia grass and temperate grasses can show limited or asymmetric IgE cross-reactivity.

Specimen Types

Serum from venous blood.
Serum from capillary blood, when validated by the testing laboratory.
Plasma collected with suitable anticoagulants, depending on the assay and laboratory validation.

Measurement Methods

In-vitro allergen-specific IgE immunoassay using Bahia grass pollen extract.
Enzyme-linked immunosorbent assay (ELISA).
Fluorescence enzyme immunoassay or other solid-phase automated immunoassays.
Historically, radioallergosorbent testing (RAST).
Component-resolved or molecular assays may measure IgE to individual Bahia grass allergens, such as Pas n 1, but these are distinct from extract-based G017-IgE testing.

Test Preparation and Influencing Factors

No fasting or other special preparation is generally required for an allergy blood test.
Patients should report all prescription medicines, over-the-counter medicines, and supplements. Antihistamines usually do not affect serum-specific IgE results, although they can interfere with skin-prick testing.
Medicines should not be stopped unless directed by a healthcare professional.
The result should be interpreted with the timing of symptoms, geographic and occupational exposure, and local Bahia grass pollen seasons.
A positive result indicates sensitization and does not independently establish symptomatic allergy or predict reaction severity.
Total IgE elevation, other pollen sensitizations, and cross-reactive grass-pollen allergens may complicate interpretation.
Specimens should be collected, transported, and stored according to the performing laboratory’s requirements. Avoiding inappropriate storage and repeated freeze-thaw cycles helps preserve specimen integrity.