Measurement of epidermal hydration and skin ph in infants with atopic dermatitis before and after a bath

Introduction: The skin barrier function resides primarily in the stratum corneum (SC). Defect in SC hydration and skin surface pH leads to barrier impairment causing atopic dermatitis (AD). We have noticed a clinical improvement in infants with AD after a bath. We aimed to assess barrier functions in infants with AD before and after a single bath. There are no large controlled studies that clarify the optimal parameters of bathing. However, there are few studies recommending bath in AD. We proposed a "twenty minutes immersion bath." Materials and Methods: We conducted an interventional analytic study without comparison group. The main instruments used were the corneometer and skin pH meter. Results: The measured values of SC hydration were significantly higher on the lesional skin immediately after a bath (P < 0.001). The mean SC hydration dropped dramatically within one hour and gradually reduced further over the next three hours. However, healthy looking skin had short climb and slow drop of SC hydration. The measured values of skin pH were lower on the lesional skin after bathing (P = 0.026). Discussion: An immersion bath improves SC hydration and helps to maintain skin pH and warrants further evaluation in the context of atopic dermatitis.