Biomarker: M006-IgE Alternaria alternata

Overview

M006-IgE measures immunoglobulin E antibodies directed against the mold Alternaria alternata, an airborne fungus associated with allergic sensitization. IgE is an antibody involved in type I hypersensitivity reactions, including allergic rhinitis, conjunctivitis, and asthma. A detectable result indicates sensitization but does not by itself confirm symptomatic allergy, predict reaction severity, or establish that Alternaria is the cause of a patient’s symptoms. The test is clinically useful when interpreted with exposure history, symptoms, physical examination, and other allergy testing.

Clinical Use Cases

Supporting evaluation of suspected mold-related allergic rhinitis, conjunctivitis, asthma, or other IgE-mediated respiratory symptoms.
Identifying sensitization to A. alternata in patients with suspected mold allergy.
Supporting assessment of allergic asthma when symptoms may be associated with mold exposure.
Comparing sensitization to whole A. alternata extract with component allergens such as Alt a 1 in specialized allergy evaluation.
Supporting research on associations between Alternaria sensitization, asthma, rhinitis, and environmental mold exposure.

Specimen Types

Venous blood serum is the typical specimen for allergen-specific IgE measurement.
Plasma may be accepted by some assay systems, including EDTA- or heparin-treated plasma, according to laboratory requirements.

Measurement Methods

Fluorescent enzyme immunoassay or other solid-phase immunoassay for quantitative allergen-specific IgE.
Chemiluminescent immunoassay.
Enzyme-linked immunosorbent assay.
Radioallergosorbent testing and radioimmunoassay are historical or specialized methods and have largely been replaced by enzyme-, fluorescence-, or chemiluminescence-based assays.
Skin-prick testing can assess sensitization to A. alternata but is not a measurement of serum M006-IgE.

Test Preparation and Influencing Factors

No fasting or other special preparation is usually required for an allergy blood test.
Patients should report all medications and supplements. Some general allergy-testing instructions may mention antihistamine restriction, but antihistamines generally do not interfere with serum-specific IgE testing; medication changes should follow the ordering clinician’s instructions.
Results should be interpreted with a focused history of symptoms, timing, environmental exposure, and other suspected allergens.
A positive result indicates immunologic sensitization, not necessarily clinically relevant allergy. A negative result does not completely exclude allergy when the history is strongly suggestive.
Assay platforms, allergen extracts, reporting units, detection limits, and reference categories may differ between laboratories. Results should be interpreted using the reporting laboratory’s reference range.
Total IgE concentration, age, atopic status, concurrent allergic disease, and sensitization to other molds may influence interpretation, but total IgE does not replace allergen-specific testing.