Immunology of atopic dermatitis.

Atopic dermatitis is a chronic eczematous skin disease which characteristically starts early in life and later tends to disappear. Genetic predisposition seems important for the development of the disease. The immune system is involved through a lymphocyte-mediated inflammation in the skin creating the eczema, and an increased incidence of type I and possibly type IV allergies induced by environmental allergens. Recent findings of a changed concentration of some interleukins in atopic patients support the evidence for an increased T-lymphocyte activation and may explain the increased amount of polyclonal IgE in many of the patients. Hypothetically, atopic dermatitis can be considered to be due to an inborn error of the maturation of epithelial tissue. Maturation of epithelial tissue is essential for both the appearance of normal skin and for correct maturation of the cell-mediated immune system. The immune deviation is later more or less corrected through maturation which explains why the disease in most patients disappears in childhood. However, it still leaves a certain increased capacity for inflammation of the atopic persons.