On January 5, 2017, an expert panel sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, issued clinical guidelines to aid health care providers in early introduction of peanut-containing foods to infants to prevent the development of peanut allergy. The Larner College of Medicine (COM) medical communications staff interviewed pediatric allergy specialist Elizabeth Jaffe, M.D., Ph.D., clinical associate professor of pediatrics and a clinician at Timber Lane Allergy & Asthma Associates in South Burlington, Vt., regarding the revised guidelines. Jaffe received a Ph.D. in genetics from the University of Washington in 1988, an M.D. from the University of Washington in 1993 and completed a pediatrics residency at UVM in 1997 and a fellowship in allergy/immunology at McGill University in Montreal, Quebec, Canada, in 2000.
Larner COM: Can you provide us with some background on peanut allergies?
Jaffe: Peanut allergy has been on the rise for decades in Westernized countries. Part of this increase may have been due to advice to delay introduction of potentially allergenic foods, such as peanut, until after the first year of life. These recommendations were based on the best evidence at the time and the belief that the immature infant gut had not yet developed the capacity for full immunological tolerance. However, more recent studies indicate that early consumption of peanut in infancy is associated with a significantly lower incidence of peanut allergy.
Larner COM: What research has been conducted to investigate the issue of peanut allergy and what has it shown?
Jaffe: The first study was published in 2008 by Du Toit et al. in the Journal of Allergy and Clinical Immunology, Volume 122 (5):984-991. They noted that the incidence of peanut allergy in Jewish children in the UK is 10-fold higher than that of Israeli children. In Israel, peanut is frequently consumed by infants in the form of a dissolvable, “Cheetos”-type food called Bamba. In the UK, babies are rarely given any peanut in the first year of life. This led to a comparison study of the prevalence of development of peanut allergy in high-risk children randomized to either completely avoid peanut in the first five years of life or to eat peanut as early as four to 11 months of age. This is the LEAP (Learning Early about Peanut) study published by Du Toit et al. in the New England Journal of Medicine 2015; 372:803-813. This randomized controlled trial enrolled 640 children, four to 11 months of age, at high risk for allergy (severe eczema with or without egg allergy). Half of the children regularly consumed peanut – the equivalent of 1 teaspoon of peanut butter three times per week – from infancy to five years of age, and the other half completely avoided it. The results were that 17.2 percent of the children in the peanut avoidance group had food challenge-proven peanut allergy versus 3.2 percent in the peanut consumption group. The risk reduction was 86 percent in the peanut ingestion group without a positive skin test for allergy to peanut and 70 percent with a small positive skin test for allergy to peanut at start of the study.
Based on these data, an expert panel sponsored by NIAID issued new clinical guidelines on January 5, 2017. The expert panel provides three separate guidelines for infants at various levels of risk for developing peanut allergy, which are as follows:
1. Guideline for infants deemed at high risk of developing peanut allergy because they already have severe eczema and/ or another food allergy:
The expert panel recommends that these infants have peanut-containing foods introduced into their diets as early as four to six months of age to reduce the risk of developing peanut allergy, if they are cleared to do so. The health care provider may choose to perform an allergy blood test (IgE level specific to peanut) or send the infant to an allergist for a skin prick test, and if necessary, an in-office oral food challenge. The results of these tests will help decide if and how peanut should be safely introduced into the infant’s diet.
2. Guideline for infants with mild or moderate eczema:
The expert panel recommends that these infants should have peanut-containing foods introduced into their diets around 6 months of age to reduce the risk of peanut allergy. They do not need special testing beforehand.
3. Guideline for infants without eczema or any food allergy:
The expert panel recommends that peanut-containing foods can be freely introduced into their diets.
Larner COM: What are the takeaway messages for providers and parents?
Jaffe: In all cases, infants should start other solid foods before they are introduced to peanut-containing foods. Peanut butter is too thick to be fed directly to infants. Smooth peanut butter should be thinned with pureed fruit or warm water. Alternatively, Bamba, the peanut infant food used in Israel, is available for purchase on Amazon.
For those with concerns about introduction of solids in the first six months of life, there is currently an ongoing study called EAT (Enquiring About Tolerance), which randomized 1,303 infants to either avoid or introduce six potentially allergenic foods, including cow’s milk, peanut, egg, sesame, and cod, starting at three months of age. In this study, early introduction of foods at three months of age has not been shown to interfere with the frequency of breast-feeding or with nutritional status. It is too early to determine whether early introduction of these foods will also decrease the prevalence of these food allergies.