# Basophil Activation Test (BAT) for Diagnosing LTP Food Allergy: Where Do We Stand Now? A Systematic Review

## TL;DR

This review evaluates the use of the basophil activation test (BAT) for diagnosing LTP food allergy, a condition with severe risks during traditional testing.

## Contribution

The paper systematically reviews BAT's potential to replace oral food challenges in LTP allergy diagnosis.

## Key findings

- BAT is a promising functional assay for diagnosing food allergies with reduced risk compared to oral food challenges.
- Evidence for BAT's use in LTP allergy is limited despite its inclusion in EAACI guidelines.
- More research is needed to confirm BAT's effectiveness in specific LTP allergy scenarios.

## Abstract

LTP allergy and its accurate diagnosis remain a challenge in modern allergology. Patients sensitized to lipid transfer proteins (LTPs) present a wide range of symptoms, from mild manifestations—such as oral allergy syndrome, urticaria, and angioedema—to severe systemic reactions, including anaphylaxis. Oral food challenges (OFCs), the gold standard in food allergy diagnostics, are problematic in this group of patients due to the high risk of life-threatening reactions during the procedure. The basophil activation test (BAT), a functional assay based on flow cytometry, is a promising diagnostic tool that may benefit many food-allergic patients by reducing the need for OFCs. In 2023, BAT was incorporated into selected diagnostic pathways for food sensitization in the guidelines issued by the European Academy of Allergy and Clinical Immunology (EAACI). While many studies have investigated BAT in the context of peanut allergy, evidence regarding its application in LTP allergy remains limited. In this systematic review, we analyzed the currently available studies on the use of BAT in the diagnosis of LTP sensitization and evaluated its potential to supplement or even replace OFCs in specific clinical scenarios.