Atopic Dermatitis and its Relation to Food Allergy

François Graham; Philippe A. Eigenmann


Curr Opin Allergy Clin Immunol. 2020;20(3):305-310. 

In This Article

Early Introduction of Allergenic Foods

Early introduction of allergenic foods for prevention of food allergy in patients with atopic dermatitis has been investigated for peanuts,[56,57] eggs,[58,59] and multiple foods.[60] The Learning Early about Peanut Allergy (LEAP) study was the first interventional study to address the issue.[56] This landmark study consisted of a double-blind placebo-controlled trial in which high-risk infants 4 to 11 months of age (moderate-to-severe atopic dermatitis and/or egg allergy) were separated in high peanut consumption or no consumption groups for 60 months. A much lower incidence of peanut allergies was seen in the group with high peanut consumption (1.9%) when compared with the avoidance group (13.7%), suggesting that infants with allergic potential became tolerant to peanuts after early peanut exposure. A follow-up study with the same cohort (LEAP-On) showed that a 12-month period of peanut avoidance at five years of age was not associated with an increase in prevalence of food allergy in the high consumption group, suggesting that primary prevention was sustained rather than a temporary phenomenon. Similar positive results were found in high-risk groups with atopic dermatitis with early introduction of egg[58,59] and recently with multiple foods.[60] In the Enquiring About Tolerance (EAT) study, infants with moderate-to-severe atopic dermatitis developed significantly less food allergy to one or more foods, and less egg allergy with early introduction of allergenic foods (peanut, cooked egg, cow's milk, sesame, whitefish, and wheat) at the age of three months compared with standard introduction at six months.[60] This trial had previously been unsuccessful at preventing food allergy using an intention-to-treat analysis in infants recruited from the general population.[61] One caveat of early introduction is the safety of performing such a task, as some infants with atopic dermatitis may already be allergic at time of introduction. This is highlighted by the Solids Timing for Allergy Research trial where a high rate of allergic-reaction in egg-sensitized children at the age of four months forced an early termination of the trial.[58] Thus, guidelines generally suggest performing SPTs and/or sIgE before early introduction of allergenic foods in children with moderate-to-severe atopic dermatitis.[62,63] In addition, real-life parents' assiduity at regularly introducing allergenic foods may not be as stringent as in the aforementioned study protocols (patients were instructed to eat three times a week), depending on family's personal dietary habits, which could ultimately limit the benefit of early introduction. Further studies are needed to better determine the best approach of introducing these allergenic foods in these high-risk patients for the prevention of food allergy.