Xerosis: a modern view on the problem

Xerosis — a multifactorial condition, occurring associated with impaired barrier function of the epidermis, decreased hydration of the stratum corneum and changes in the lipid matrix. The review systematizes current understanding of pathogenesis, classification and treatment options for skin dryness. Special attention is paid to the role of natural moisturizing factor (NMF), epidermal lipid barrier and aquaporins (especially AQP-3) in regulating water exchange and maintaining the structural integrity of the skin cover. Endogenous, exogenous and iatrogenic causes, including impact of climate, occupational factors, systemic diseases and drugs, have been considered. Clinical importance of differential diagnosis of xerosis as an independent condition and as a symptom of dermatoses and somatic pathology has been noted. Current therapeutic strategies have been presented: creation of occlusion barrier, substitution therapy with NMF components, application of emollients, use of osmotic and hygroscopic moisturizers (e.g., glycerin and hyaluronic acid), as well as the recovery of the lipid layer by ceramide-containing systems. Pharmacological modulation of the expression of aquaporins is recognized as a promising direction. Safety of long-term occlusion and dependence of hygroscopic agent efficacy on ambient humidity are discussed separately. The need for a comprehensive, pathogenetically substantiated approach and individualization of care is emphasized; clinical manifestations (dryness, tightness, desquamation, microfissures, itching) are considered in the context of their impact on the quality of life.