Background: Active dermatitis causes a disturbance in skin barrier function. This can be evaluated by the measurement of transepidermal water loss (TEWL) and percutaneous absorption of hydrocortisone.
Objective: The study objective was to evaluate changes in skin barrier function during treatment of atopic dermatitis.
Methods: Nine patients with widespread atopic dermatitis were studied longitudinally by measuring the severity of the dermatitis and TEWL at intervals of 1 to 3 days. Percutaneous absorption of hydrocortisone was measured at entry and during treatment.
Results: At entry, both TEWL and percutaneous absorption of hydrocortisone were elevated. Four to six days later, a significant decline was observed in both variables, indicating rapid improvement in skin barrier function. Individual changes in TEWL correlated with the changes in the systemic absorption of hydrocortisone.
Conclusion: TEWL reflects changes in the systemic absorption of topical hydrocortisone during treatment of atopic dermatitis.