Mustard Allergy in Children and Cross-reaction: Case Report

Aims: Food allergy to mustard is often unrecognised in children; however, it deserves early recognition as a potentially severe immunoglobulin e (IgE)--mediated allergy with a risk of anaphylaxis. The aim of this work is to show the value of performing an oral challenge test to confirm the diagnosis of mustard allergy.

Presentation of Case: We report the observation of a child who presented with allergy to yellow mustard with all the allergological work-up performed.

Discussion: The diagnosis of mustard allergy is delicate; on the basis of the clinical history and the food investigation, as mustard is consumed mainly in a masked form. Cross-allergies are common with mugwort, nuts and rosacea. No threshold value for skin tests or specific IgE can be considered sufficient to confirm or not the diagnosis of food allergy or the secondary acquisition of tolerance to mustard.

Conclusion: Oral challenge test is the gold standard for confirming the diagnosis of food allergy; reducing the risk of accidental exposure; validating or not the avoidance diet; and improving quality of life.