Biomarker: M004-IgE Mucor racemosus

Overview

M004-IgE Mucor racemosus measures serum IgE antibodies specific to the mold Mucor racemosus, an environmental fungus associated with fungal sensitization. A detectable result indicates immunologic sensitization, but it does not by itself establish that exposure causes clinical allergy or symptoms. Sensitization to M. racemosus has been reported in people with asthma, allergic rhinitis, sinus disease, and other suspected mold-related respiratory conditions. The test is clinically useful as an adjunct to the patient’s exposure history, symptoms, and other allergy evaluation when identifying possible mold triggers.

Clinical Use Cases

Evaluating suspected IgE-mediated sensitivity to Mucor racemosus.
Supporting assessment of mold-associated allergic rhinitis, asthma, or sinus symptoms.
Identifying possible fungal sensitization in patients with suspected environmental or occupational exposure.
Complementing skin-prick testing when skin testing is unsuitable, unavailable, or affected by medications or skin disease.
Supporting research studies that characterize fungal sensitization patterns in patients with allergic respiratory disease.

Specimen Types

Venous blood serum, typically collected in a serum gel or red-top tube.
Plasma or other specimen types should only be used if specifically validated and accepted by the performing laboratory.

Measurement Methods

Allergen-specific IgE immunoassay using an extract of Mucor racemosus.
Fluorescence enzyme immunoassay, including ImmunoCAP-based methods.
Other validated immunoassays, such as enzyme-linked or immunoblot-based assays, may be used by individual laboratories.
Older research methods include radioallergosorbent testing, although this is not the usual current clinical method.

Test Preparation and Influencing Factors

No fasting or other special preparation is generally required for an allergy blood test.
Patients should report all medications and supplements. Medications should not be stopped unless directed by a health care professional.
Antihistamines generally do not interfere with blood-based specific-IgE testing, although medication instructions may vary if skin testing is also planned.
Results should be interpreted with symptoms, exposure history, age, geographic region, and other allergy testing because sensitization does not necessarily indicate clinically relevant allergy.
Cross-reactivity and nonspecific binding may contribute to positive results, particularly in people with markedly elevated total IgE.
Results may vary with the allergen extract, assay platform, calibration, and laboratory reporting thresholds.
Prior allergen immunotherapy may limit the usefulness of specific-IgE testing for determining residual clinical sensitivity.