Recent Improvements in the Pathogenesis of Atopic Dermatitis

Atopic dermatitis (AD) is a multifactorial skin disease manifested by the interaction between environmental factors, immune system and the genes predisposing to the disease. It affects the quality of life of patients and their family considerably. The prevelance for children is 10-20% in developed countries, while frequency of AD is considered as rising all over the world. According to the studies conducted in our country, the frequency is about 4.9% to 8.1%. Currently, there are two main hypothesis accepted to explain disease pathogenesis; inside-outside and outside-inside hypotheses. However, these are even not able to define the pathogenetic mechanisms underlying AD in all details. In the recent years, genetic studies have revealed significant role of filaggrin gene in the pathogenesis of AD. Further, epidermal barier dysfunction is found to play an important role in the pathogenesis by causing dryness and pruritus in skin and cause predisposition to infections with some viruses and bacteria. In this review, recent data about genetic, immunologic mechanisms and the dysfunction of epidermal barier complex underlying the pathogenesis of AD will be discussed.