Atopic Dermatitis Linked to Pediatric Food Allergy

Investigators report that the skin condition mediated the association between a a interleukin-4 receptor agonist variant and food allergy.

A new cohort study evaluated the potential shared genetic risk factors of atopic dermatitis and food allergy in pediatric populations and suggested that the atopic disease mediated the association between a interleukin-4 receptor agonist (IL4Rα) variant and food allergy.

Investigators led by Tina Banzon, MD, Pediatric Asthma & Allergic Conditions, Clinical & Laboratory Immunology, Boston Children’s Hospital, believed the variant was associated with an increased risk of severe food allergy reactions.

The findings were presented at the 2021 American College of Allergy, Asthma, and Immunology (ACAAI) Scientific Meeting in New Orleans.

The Methods

Banzon and colleagues enrolled a total of 429 elementary school-age children with asthma into the School Inner-City Asthma Study. Each participating child underwent genotyping for the IL4Rα Q576R polymorphism.

The investigators then administered surveys that determined physician diagnosed food allergy as well as associated allergic responses.

The genotypes were modeled as a 3-group categorical variable: Q/Q, Q/R, or R/R genotypes, with the Q/Q genotype being used as the reference group.

In order to test their hypothesis that atopic dermatitis mediated the association between genotype and food allergy, Banzon and investigators performed 2 adjusted logistic regression models.

In the first model, atopic dermatitis was predicted from genotype. In the second model, food allergy was predicted from atopic dermatitis and genotype.

Finally, the investigators evaluated the association between genotype and severe food allergy reaction, which was defined as trouble breathing, using multivariate models.

The Findings

Overall, investigators reported that 81 (18.9%) of all participants were allergic to at least 1 food, with 60 (14%) reporting a severe reaction.

Genotype status was not associated with food allergy diagnosis in the overall cohort. However, the IL4Rα Q576R polymorphism (Q/R or R/R) was associated with atopic dermatitis diagnosis (OR 1.67 [0.96, 2.91] for R/R, OR 1.54 [0.93, 2.53] for QR).

Additionally, atopic dermatitis was associated with food allergy diagnosis (OR 3.86 [2.23, 6.67]).

In a cohort of asthmatic participants with reported food allergy reactions, investigators noted that having either risk allele (Q/R or R/R) was associated with increased food allergy reaction severity.

Banzon and colleagues concluded that, in a cohort of asthmatic children, atopic dermatitis mediated the association between a IL4Rα variant and food allergy

“This variant is associated with increased risk of severe food allergy reactions,” the team wrote.