Documents from the SIAIP Commissions

Issue 1 - 2026

Basophil activation test (BAT): Clinical and research relevance in allergy diagnostics

Authors

Stefania Arasi , Malgorzata Niegowska , Davide Caimmi , Fernanda Chiera , Giulio Dinardo , Arianna Giannetti , Serena Gracci , Carla Mastrorilli , Luca Pecoraro , Michele Miraglia Del Giudice , Gian Luigi Marseglia , Roberto Bernardini

Key words: Basophil Activation Test (BAT), allergy diagnostics, food allergy, drug allergy, personalized medicine
DOI: 10.53151/2531-3916/2026-1906
Publication Date: 2026-03-27

Abstract

The basophil activation test (BAT) is transitioning from a research assay to a clinically actionable tool. By capturing IgE-mediated basophil degranulation in vitro, BAT can complement history, skin testing, and serum specific IgE. High-quality studies in food allergy show the strongest evidence for peanut and sesame, where BAT improves diagnostic accuracy and may obviate oral food challenges. In drug allergy, BAT’s high specificity can confirm culprit sensitization in defined contexts and, uniquely, screen potential alternative agents when drug provocation is hazardous. Additional applications include confirming clinically relevant sensitization prior to respiratory allergen immunotherapy, refining diagnosis and risk stratification in Hymenoptera venom allergy, and endotyping in chronic urticaria.
Implementation has been limited by logistics, the need for experienced flow-cytometry staff, and historical heterogeneity in markers, panels, and positivity thresholds. Crucially, the EAACI published an externally quality-assured protocol with a standard operating procedure. This standardization establishes a foundation for controlled multicenter research.
Importantly, in selected scenarios – such as some equivocal IgE-mediated food allergies and severe immediate drug reactions where provocation test may be unsafe – BAT can help reduce or avoid the need for provocation testing when available and appropriately interpreted. Priority next steps are broad protocol adoption and prospective, multicenter validation to define robust, setting-specific decision thresholds and patient-relevant outcomes.

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Authors

Stefania Arasi - Pediatric Allergology Unit, Bambino Gesù Children’s Hospital (IRCCS), Rome, Italy

Malgorzata Niegowska - Pediatric Allergology Unit, Bambino Gesù Children’s Hospital (IRCCS), Rome, Italy https://orcid.org/0009-0005-9431-5015

Davide Caimmi - Allergy Unit, CHU de Montpellier, Montpellier, France; IDESP, UMR 1318, INSERM, University of Montpellier, Montpellier, France

Fernanda Chiera - Department of Pediatrics, Giovanni Paolo II Hospital, Lamezia Terme, ASP Catanzaro, Italy https://orcid.org/0000-0003-2968-033X

Giulio Dinardo - Department of Woman, Child and General and Specialized Surgery, University of Campania ‘Luigi Vanvitelli’, Naples, Italy

Arianna Giannetti - Pediatric Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy https://orcid.org/0000-0001-8243-9727

Serena Gracci - Pediatrics and Neonatology Unit, Maternal and Child Department, San Giuseppe Hospital, Empoli, Azienda USL Toscana Centro, Italy https://orcid.org/0009-0002-1530-7817

Carla Mastrorilli - Department of Pediatrics, University Hospital Consortium Corporation Polyclinic of Bari, Pediatric Hospital Giovanni XXIII, Bari, Italy https://orcid.org/0000-0003-2481-7229

Luca Pecoraro - Pediatric Unit, Ospedale Vito Fazzi, ASL Lecce, Lecce, Italy

Michele Miraglia Del Giudice - Department of Woman, Child and General and Specialized Surgery, University of Campania “Luigi Vanvitelli,” Naples, Italy

Gian Luigi Marseglia - Pediatric Unit, Department of Clinical, Surgical, Diagnostic, and Pediatric Sciences, University of Pavia, Pavia, Italy https://orcid.org/0000-0003-3662-0159

Roberto Bernardini - Pediatric and Neonatology Unit, Maternal and Child Department, San Giuseppe Hospital, Azienda USL Toscana Centro, Empoli, Italy

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How to Cite
Arasi, S., Niegowska, M. A., Caimmi, D., Chiera, F., Dinardo, G., Giannetti, A., Gracci, S. ., Mastrorilli, C., Pecoraro, L., Miraglia Del Giudice, M., Marseglia, G. L. ., & Bernardini, R. (2026). Basophil activation test (BAT): Clinical and research relevance in allergy diagnostics. Italian Journal of Pediatric Allergy and Immunology, 40(1), 36–43. https://doi.org/10.53151/2531-3916/2026-1906
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