[Xerosis: a dysfunction of the epidermal barrier].

Xerosis or dry skin is a common skin disorder among the general population. It is characterized clinically by rough, scaly, and often itchy skin. This disorder is present in the course of some dermatoses such as atopic dermatitis, although it can also occur in healthy individuals if a combination of certain etiologic factors is present. It is characterized pathophysiologically by a disrupted stratum corneum, dehydration, and impaired keratinocyte differentiation. Treatment of xerosis should seek to restore physiologic lipids in the epidermis and provide substances that facilitate epidermal differentiation.