Study suggests new strategies to combat peanut allergies bring both progress and controversy

July 2, 2020

There are a number of ways clinicians can tackle peanut allergies, but allergy screening and early peanut exposure are still up for debate.

Peanut allergies are one of the most common food allergies in children, with prevalence increasing significantly over the last few decades. Emerging evidence supports early peanut introduction as a tool to combat peanut allergies, but this is still considered a controversial step in allergy management.

A recent report set out to investigate advances in peanut allergy diagnosis and treatment, as well as some of the barriers to accepting these therapies. The study,1 published in Pediatrics, reveals that although there is a lot of progress being made in mitigating peanut allergies, there is still a lot of debate about the best steps to take.

Peanut allergies affect roughly 1% to 3% of children and although the number is relatively small, the impact is great. Peanut allergies have a significant negative impact on quality of life, highlighting the importance of accurate diagnosis and management early on, the study notes.

Whereas peanut allergies may be more common in children with immediate family members who also have a peanut allergy, peanut allergies can be rooted in both genetic and environmental factors, according to the report. For example, the study notes some evidence pointing to vitamin D deficiencies and high latitudes being associated with higher rates of both peanut allergies and anaphylactic reactions to exposures.

The report highlights recent acceptance that the dual-allergen exposure hypothesis2 supports the idea that avoidance of certain foods—like peanuts—in a child’s early years can lead to an increased chance of allergic reactions later. Specifically, the theory suggests that allergen exposure in these children happens through cutaneous exposure whereas eating allergenic foods appears to increase immune tolerance. This theory is related to mutations of the FLG gene, which has been linked to atopic dermatitis. Therefore, early peanut introduction has emerged as a preventive tool in mitigating peanut allergies.

Early peanut introduction has been tested in a number of studies over more than a decade, with one of the most recent reports indicating that allergy risk is reduced when peanuts are introduced to children between 4 and 11 months of age.3 These studies have led the National Institute of Allergy and Infectious Diseases (NIAID) to release a guideline on preventing peanut allergies in 2017 that included a recommendation to introduce peanut-containing foods as early as 4 to 6 months of age in infants with severe eczema and/or egg allergies.4

Despites strong recommendations in the United States and abroad, a number of questions about using peanut exposure to combat allergy development remain. A few of these include the amount and frequency of peanut products that have to be ingested to the best effect, and how well this therapy works on children who are at lower risk of developing peanut allergies. There is also some controversy as to whether high-risk infants should have additional screenings before starting peanut introduction. These tests have high false negative rates and although the guidelines suggest additional testing for children with other severe allergies, international recommendations do not. This could lead to a slippery slope when it comes to costly screening, the study notes. There are certain criteria that should be used when considering preemptive testing for peanut allergies, and clinicians should consider balance and practicality when making a decision on testing protocol. Medically supervised oral food challenges are the “gold standard” for peanut allergy diagnosis. Development of better—more effective and less risky—testing methods are still needed, the authors add.

The study also tackles the controversy surrounding peanut bans in schools and other facilities, noting the low risk of accidental exposure in these environments, as well as low efficacy of these bans in preventing accidental ingestion. The more pressing issue, the study notes, is how ill-prepared most of these facilities are for dealing with allergic reactions when they do occur.

Immunotherapies like early peanut exposure have been shown to have a significant effect on the development of peanut allergies, but this treatment remains controversial to some for the level of risk it presents with uncertain benefit. The focus should be more research aimed at home to improve quality of life in children with peanut allergies.

References

1. Abrams EM, Chan ES, Sicherer S. Peanut allergy: new advances and ongoing controversies. Pediatrics. 2020:145(5):e20192102. doi:10.1542/peds.2019-2102

2. West C. Introduction of complementary foods to infants. Annals of Nutrition and Metabolism. 2017:70(2):47-54. doi:10.1159/000457928

3. Ierodiakonou D, Garcia-Larsen V, Logan A et al. Timing of allergenic food introduction to the infant diet and risk of allergic or autoimmune disease. JAMA. 2016: 316(11):1181. doi:10.1001/jama.2016.12623

4. Togias A, Cooper SF, Acebal ML, et al. Addendum guidelines for the prevention of peanut allergy in the United States: report of the National Institute of Allergy and Infectious Diseases-sponsored expert panel. J Allergy Clin Immunol. 2017:139(1):29-44. doi:10.1016/j.jaci.2016.10.010