Presentation and Management of Food Allergy in Breastfed Infants and Risks of Maternal Elimination Diets

Breastfeeding is currently recommended as the optimal source of nutrition to infants. However, there are several studies that have shown clinical IgE- and non–IgE-mediated reactions to foods in exclusively breastfeeding infants, specifically to cow's milk, egg, peanut, and fish. Literature suggests that antigenic food proteins present in human milk can be found in substantial enough amounts to elicit clinical reactions in some, already-sensitized infants, including anaphylaxis, eczema exacerbation, and non–IgE-mediated gastrointestinal food-allergic syndromes. Diagnosis of food allergy in a breastfed infant and identification of the trigger foods in the mother's diet can be especially challenging in infants with delayed symptoms, such as eczema and gastrointestinal symptoms. Management is further complicated in infants with atopic dermatitis, who have increased caloric needs and therefore in whom nutrition is an extremely important factor for growth and development. One needs to balance possible benefits with risks of further food sensitization through the skin when foods are eliminated from their diets. We review here the literature on clinical presentation and evidence for food allergy in exclusively breastfed infants, including the presence of food antigens in human milk. Incorporating clinical experience and the available data, which largely come from case reports and small, nonrandomized studies performed in referral centers with several limitations, we propose a novel algorithm to diagnosis and management, with emphasis on nutritional considerations.