Non-Releasers in the Basophil Activation Test: A Roadmap for the Correct Reporting and Interpretation

Area of Science:

• Immunology
• Allergy Diagnostics

Background:

• The basophil activation test (BAT) is a flow cytometry method for diagnosing IgE-mediated allergic reactions.
• A significant challenge in BAT is the "non-releaser" phenotype, where basophils fail to degranulate in vitro, occurring in 10-20% of subjects.
• Lack of standardized nomenclature for non-releaser results hinders accurate clinical interpretation and BAT implementation.

Purpose of the Study:

• To review intrinsic and extrinsic factors contributing to the basophil non-releaser phenotype in BAT.
• To propose a standardized nomenclature for reporting inconclusive BAT results.
• To suggest diagnostic algorithms for interpreting non-releaser status in clinical practice.

Main Methods:

• Literature review focusing on factors affecting basophil degranulation in vitro.
• Analysis of existing guidelines, including the STAndards for the Reporting of Diagnostic accuracy studies (STARD).
• Development of a proposed nomenclature and diagnostic algorithms for non-releaser phenotypes.

Main Results:

• Identified various intrinsic (e.g., patient-related) and extrinsic (e.g., pre-analytical) factors causing the non-releaser phenotype.
• Emphasized the necessity of reporting non-releaser status as per STARD guidelines for accurate performance metrics.
• Proposed a unified nomenclature and interpretation algorithms to address inconclusive BAT results.

Conclusions:

• Standardizing the reporting and interpretation of basophil non-releaser status is crucial for improving the clinical utility of BAT.
• Addressing the non-releaser phenotype through clear nomenclature and algorithms will enhance diagnostic accuracy in allergy testing.
• Consistent reporting of non-releasers is essential for the broader implementation of BAT in routine clinical practice.