Multiple Food Allergies in Children: Distinct Phenotypes Identified | Healio

Philadelphia – Children with multiple food allergies don’t present with a single, uniform clinical picture. Instead, distinct patterns, or phenotypes, emerge depending on the specific combination of allergens involved, according to research presented at the American Academy of Allergy, Asthma & Immunology (AAAAI) Annual Meeting. This understanding could pave the way for more targeted screenings and interventions, potentially improving management for these children.

The findings, stemming from a large, multi-site study, highlight the complexity of food allergies and move beyond the simple categorization of “having” or “not having” a food allergy. “There’s just a lot of different constellations of food allergies that people have,” explained Christopher Warren, PhD, director of population health research at the Center for Food Allergy & Asthma Research, Northwestern University Feinberg School of Medicine, in an interview with Healio. The research aims to address questions like whether the severity of allergies matters, if certain foods tend to occur together and what the long-term outcomes are for children with multiple sensitivities.

Understanding the Scope of Multiple Food Allergies

The study analyzed data from 1,382 children under the age of 12 with food allergies, drawn from a longitudinal cohort supported by the National Institute of Allergy and Infectious Diseases. Researchers assessed allergy status, demographics, and clinical details during annual visits, supplemented by caregiver and child surveys, and electronic health records. A significant 75.5% of the children included in the study were allergic to more than one food, with an average of 3.3 food allergies per child. Among those with a single food allergy, peanut, tree nut, and egg were the most common culprits.

The cohort’s demographics revealed a notable overrepresentation of Black children (38%), alongside 45% identifying as white, and a majority (60%) being boys. This diversity in socioeconomic backgrounds and household incomes adds strength to the study’s findings, according to Warren.

Identifying Allergy Clusters

Researchers identified several distinct clusters of co-occurring food allergies. The most prevalent (55%) involved allergies to both peanut and tree nuts. Another significant cluster (30%) included peanut, egg, and milk allergies. A smaller group (15%) exhibited a broader range of allergies, encompassing many different foods. These clusters weren’t random; certain food combinations appeared more frequently than others. For example, allergies to cashew and pistachio, or walnut and pecan – tree nuts with shared proteins – often occurred together. Omalizumab, a medication used to treat severe allergic asthma, has shown promise in managing multiple food allergies, but researchers are exploring more targeted approaches.

Conversely, combinations like seafood and milk, or seafood and egg, were less common. These findings align with the understanding that allergies to foods with less shared protein structures are less likely to co-occur.

Predictors of Multiple Food Allergies

The study also pinpointed several factors that increase the risk of developing multiple food allergies. Race, ethnicity, age, socioeconomic status, a personal or family history of atopic conditions (like eczema or asthma), and overall levels of IgE (an antibody associated with allergic reactions) all played a role. Notably, the severity and duration of eczema throughout childhood were strong predictors. Longer-lasting and more severe eczema was associated with a greater risk of developing allergies to multiple foods.

Implications for Targeted Interventions

The identification of these distinct phenotypes opens the door to more personalized approaches to managing food allergies. Warren suggests that targeted screenings could identify children at higher risk for specific allergy combinations. For example, children with a history of severe eczema might benefit from earlier and more comprehensive allergy testing.

the research hints at the potential for tailored treatments. For children with peanut and tree nut allergies, oral immunotherapy targeting one nut might offer benefits for the other, given their shared protein structures. This contrasts with broader approaches like omalizumab, which affects the immune system more generally. “There might be some more targeted approaches that could address multiple food allergies without doing something as fundamental as what omalizumab does to the immune system,” Warren explained.

The researchers also noted a pattern where allergies developing early in life (like egg and milk) differed from those appearing later (like finfish and shellfish). This distinction could influence treatment decisions, as early-onset allergies are sometimes outgrown, making immunotherapy less appropriate. But, reliable predictors of which allergies a child will outgrow remain elusive.

The Role of Early Life Factors and Future Research

The study reinforces the importance of addressing eczema and skin barrier dysfunction in early childhood. These factors are now recognized as key drivers of atopic diseases, including food allergies. This understanding underpins current recommendations for early introduction of peanuts to infants to prevent peanut allergy. However, Warren emphasizes that even mild eczema warrants attention, as it can be a harbinger of future allergic sensitivities.

“Clinicians should prioritize this eczema and provide the right treatment,” Warren said, “to help prevent or detect food allergy early when This proves easier to mitigate.”

The FORWARD cohort continues to grow, now encompassing nearly 1,600 children, and Warren anticipates further insights will emerge as the data matures. “Stay tuned for a lot more coming out of this cohort,” he said. “It’s a gift that keeps on giving.”

For more information:

Christopher Warren, PhD can be reached at [email protected].

You can find more information about food allergies and current research on the Food Allergy Research & Education (FARE) website. The National Institute of Allergy and Infectious Diseases (NIAID) also provides resources and updates on allergy research. For guidance on managing food allergies, consult with a qualified allergist or healthcare provider.