Another interesting area of research is whether there are techniques available to prevent the development of food allergy. Much of this work came from an observation described almost a decade ago (J Clin All Immunol. 2008; 122: 984-91). Researchers found a difference between two groups of children of Jewish ancestry, those living in the United Kingdom and Israel. The kids in England were found to have higher rates of peanut allergy compared with the kids in Israel.
Several hypotheses were developed to explain these differences; Vitamin D exposure from sunlight exposure differences, differences in childhood infections and dietary variability. Scientists soon discovered that infants in Israel are often fed a peanut snack called Bamba very early whereas British children did not have the same early exposure to peanut.
These kids were skin tested and if negative to peanut, they were started on a diet that included a total of 6g peanut protein per week for five years. After five years the peanut ingestion was stopped. When compared with the kids who were not given peanut, the LEAP kids had an 81% risk reduction in the likelihood to develop peanut allergy (N Eng J Med, 2015; 372: 803).
A second study called LEAP-On follow the same kids in the year after they stopped peanut ingestion and the effect seemed to be maintained for that 12 month period, suggestion long-term effects (N Eng J Med, 2016; 374: 1435).
Because of the convincing outcomes of this research, the National Institute of Allergy Infectious Diseases (NIAID) has recently made the following three updated recommendations to their 2010 food allergy guidelines (J Allergy Clin Immunol, 2017; 139(1): 33). They have stratified infants into three categories, with high risk infants (group 1) recommended to undergo assessment and treatment for early introduction of peanut.
As I mentioned, these results are compelling and the recommendations are paradigm-shifting. However, one of the challenges facing us in the allergy community is to identify at-risk patients and initiate early feeding in a timely manner. Too often, by the time patients are referred to our clinic, it is too late to start peanut introduction.
Therefore, the providers at the Allergy Station are currently asking for help from our local pediatric and family practice providers to identify children who may benefit from early introduction to peanut. Once identified, assessment and treatment protocols can be initiated in the primary care provider’s office or in our clinic (see Figure 1).
If you would like to discuss the possibility of early peanut introduction for your child or to address any other allergic issues, please call Dr. Travis Miller and Dr. Matthew Bowdish at the Allergy Station, 916-736-6644.
References:
1. Du Toit G, et al, Early consumption of peanuts in infancy is associated with a low prevalence of peanut allergy, J Allergy Clin Immunol. 2008; 122: 984-91.
2. Du Toit G, et al, Randomized trial of peanut consumption in infants at risk for peanut allergy. N Eng J Med. 2015; 372: 803-813. Full text available free online http://www.nejm.org/doi/full/10.1056/NEJMoa1414850#t=article
3. Du Toit G, Effect of Avoidance on Peanut Allergy after Early peanut consumption N Eng J Med. 2016; 374: 1435. Full text available free online at http://www.nejm.org/doi/full/10.1056/NEJMoa1514209
4. Togias A, 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. Full text available free online http://www.jacionline.org/article/S0091-6749(16)31222-2/pdf
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