Emollients for the prevention of atopic dermatitis.

Atopic dermatitis/Eczema (AD) is the most common chronic inflammatory skin disease affecting up to 30% of children. Eczema typically develops during infancy, characterized by pruritus, dry skin, and eczematous dermatitis/skin irritation and often represents the initial manifestation of the so-called atopic march. Thus, skin barrier dysfunction due to environmental factors and genetic predisposition paired with skin inflammation is linked to AD and consequently food sensitization, food allergy (FA) and progression of the allergic disease complex (Figure 1).1 The importance of barrier integrity for AD is supported by filaggrin (FLG). It is integral in maintaining stratum corneum integrity.1 Loss of function mutations of FLG gene confer a greater risk of AD.2 The association between mutations in the FLG gene and FA independently of AD is under debate due to conflicting epidemiological data.2 However, skin barrier dysfunction may also be relevant at subclinical levels facilitating type-2 skin inflammation which in turn reduces FLG expression.2 By connecting the dots between skin barrier dysfunction and food avoidance in the context of environmental food exposure compared to concurrent consumption, the dual-allergen exposure hypothesis has been developed. It is strongly supported by the results of the LEAP study.3 The hypothesis suggests that cutaneous allergen exposure and concurrent compromised barrier with skin inflammation while delaying food introduction results in a greater susceptibility for FA. Allergen exposure in such an inflammatory skin context is considered to promote type-2 inflammation.