Role of the skin microbiome in atopic dermatitis

Atopic dermatitis (AD) is a common inflammatory skin disorder and characterized by abnormalities in both skin barrier structures and alternations of the immune response. Molecular genetics have dramatically changed our vision of the micro-organisms colonizing the human skin and recently well-documented changes in the skin microbiome in atopic dermatitis have become evident. The microbiome shifts have been primarily documented during disease flares and localized to sites of disease predilection, e.g. folds or facial area. In contrast, active treatment has been associated with a recolonisation and higher cutaneous microbial diversity. Additionally to the known dysfunctions in barrier function of the skin (e.g. filaggrin mutations) and immunologic disturbances (e.g. Th2-shift), evidence is rising that atopic dermatitis is also connected to a dysbiosis of the microbial community without an invading pathogen. In the future the investigation of the patient's skin microbiome may have a foothold in the clinician's diagnostic repertoire and treatment of atopic dermatitis.