Review: Pathogenesis of canine atopic dermatitis: skin barrier and host-micro-organism interaction

BackgroundCanine atopic dermatitis (AD) is a common, genetically predisposed, inflammatory and pruritic skin disease. The pathogenesis of canine AD is incompletely understood. ObjectivesThe aim of this review is to provide an in-depth update on the involvement of skin barrier and host-microbiome interaction in the pathogenesis of canine AD. MethodsOnline citation databases and abstracts from international meetings were searched for publications related to skin barrier and host-microbiome interaction (e.g. bacteria, yeast, antimicrobial peptides). ResultsA total of 126 publications were identified. This review article focuses on epidermal barrier dysfunction and the interaction between cutaneous microbes (bacteria and yeasts) and the host (antimicrobial peptides). Epidemiological updates on the presence of pathogenic organisms and canine AD are also provided. Conclusions and clinical importanceMajor advances have been made in the investigation of skin barrier dysfunction in canine AD, although many questions still remain. Skin barrier dysfunction and host-microbiome interactions are emerging as primary alterations in canine AD. Based on this review, it is clear that future studies focused on the development of drugs able to restore the skin barrier and increase the natural defences against pathogenic organisms are needed.