Newer concepts of atopic dermatitis

Abstract

Atopic dermatitis is a [human] disease characterized by abnormalities related to both type 1 and type 4 immune responses, yet the skin lesions cannot be classified under either of these reaction types. The disease is difficult to define; diagnosis depends on a combination of morphologic, distributional and historical features. Skin lesions typical of atopic dermatitis are seen in a number of immune deficiency conditions, especially those characterized by depressed cell-mediated immunity, elevated IgE[immunoglobulin]E production and in some instances IgA deficiency suggesting a common disorder in the ontogeny of immunoglobulin-producing cells. Defective T [thymus-derived] lymphocyte mediation of the B [bone marrow-derived] lymphocytes producing these immunoglobulins may explain the combined cellular and humoral abnormalities observed. Homologies between T cells and epidermal cells could account for the combined immunologic and cutaneous defects seen in atopic dermatitis.