[Atopic dermatitis of the adult]

Atopic dermatitis (AD) of the adult is a common skin disease. Its prevalence has greatly increased during the past decades. AD is commonly associated with other atopic disorders. Its impact on quality of life is often underestimated. Various immunopathologic mechanisms are involved in AD: innate epidermal barrier dysfunction due to filaggrin gene mutations, innate and adaptative abnormalities of the immune system (an initial Th2 phase precedes a chronic Th1 phase), intestinal and cutaneous microbiomes dysbiosis, and environmental factors. Diagnosis of AD is clinical and there is no predictive biomarker of future severity. The main differential diagnoses are: scabies, psoriasis, cutaneous adverse reaction, cutaneous T cell lymphoma, primary immunodeficiency, and Netherton's syndrome. Therapeutic management is challenging and should integrate a therapeutic education program. Topical corticosteroids are the first line treatment, including a preliminary assessment of possible topical corticosteroids phobia. Systemic treatments are recommended in severe, chronic and resistant AD, after careful evaluation in a reference centre. Dupilumab, an IL4/IL13 inhibitor, might be the first effective targeted therapy in AD, whereas therapies that specifically target the mechanisms of pruritus represent an exciting perspective.