Revisiting the Etiology and Management of Atopic Dermatitis: A Perspective on Skin Microbiota, Bathing Habits, and Surfactant-Free Skincare

The current consensus on the pathophysiology of atopic dermatitis (AD) involves Th2/Th22 inflammation, genetic predisposition such as filaggrin mutations, and skin barrier dysfunction. Meanwhile, AD has been hypothesized to be primarily caused by the defective formation of the commensal microbial community with insufficient skin regeneration as a secondary aggravating factor. AD presents with itchy, red, swollen, and cracked skin. Conventional treatments include emollients, topical corticosteroids, calcineurin inhibitors, and newer biologics. In Japan, moist wound healing techniques that promote autologous tissue regeneration have shown promising results, which have led to the development of novel, surfactant-free moisturizers designed to combat skin dryness. Based on these findings, this perspective proposes a new etiology of AD and considers suitable countermeasures. Recommendations include limiting newborn bathing to three times per week, discontinuing soap and shampoo applications, and using bathing additives containing petroleum jelly to neutralize the residual chlorine in tap water. Cognitive behavioral therapy strategies that substitute scratching with moisturizer application are also recommended. Additional measures, including smoking cessation by both patients and family members, and stress management, may reduce disease severity. This perspective article outlines hypotheses rather than established evidence. Some suggestions (eg, bathing frequency) are based on clinical experience or emerging findings that require further study.