By Allergen Bureau

How To Predict Food Allergy Severity 

A new study has found the use of a genetic biomarker could help identify which people with food allergy are most at risk of experiencing a severe reaction.  

Clinical tests that are currently available to diagnose food allergy do not accurately indicate the severity of the allergy. Yet this is one of the most frequently asked questions for clinicians when providing information and guidance to patients and families. 

Research led by experts at the Ann and Robert H. Lurie Children’s Hospital of Chicago has tested whether having the genetic propensity to produce alpha-tryptase, a protein released by mast cells during allergic reactions, correlates with a food-allergic person’s risk of anaphylaxis. 

They found that people with alpha tryptase were more likely to have had a life-threatening anaphylaxis reaction than those without it. The same group of people were also more likely to have had a severe reaction during an oral food challenge, a test in which people are given tiny amounts of a food allergen to test how they react. 

Tryptase genotyping is a test that is already commercially available to determine whether a person has alpha-tryptase or not. The findings of this study indicate it could be used at the point of diagnosis to predict the severity of a food allergy. 

The study involved approximately 120 children with food allergies, around 100 of whom had a history of anaphylaxis or severe allergic reactions. The researchers say further studies are needed to confirm their findings and to determine how tryptase genotyping could be used to improve the management of food allergies. 

Reference: Lang et al. 2023. Severe food allergy reactions are associated with α-tryptase. Journal of Allergy and Clinical Immunology (In Press) DOI: 10.1016/j.jaci.2023.07.014