Food allergy in atopic dermatitis

Food allergy predominantly affects children rather than adult patients with atopic dermatitis (AD). Early sensitization to foods has been found to be significantly associated with AD. Three different patterns of clinical reactions to food allergens in AD patients exist: i. immediate-type reaction, ii. isolated late-type reaction, iii. combined reaction (i. + ii.). While in children allergens from cow's milk, hen's egg, soy, wheat, fish, peanut or tree nuts are mostly responsible for allergic reactions, birch-pollen related food allergens seem to play a major role in adolescent and adults with AD in Central and Northern Europe. Defects of the epidermal barrier function seem to facilitate the development of sensitization to allergens following epicutaneous exposure. The relevance of defects of the gut barrier as well as genetic characteristics associated with an increased risk for food allergy remain to be further investigated. Numerous studies focus on prevention strategies which include breast-feeding or feeding with hydrolyzed milk substitute formula during the first 4 months of life.