ABSTRACT
Atopic dermatitis (AD) is a chronically relapsing skin disorder that is associated with severe pruritis and a “classic” distribution. There are international standards for diagnosis based upon the criteria recommended by Hanifin and Rajka (1) and a standardized method for gauging severity based on the SCORAD Index (2) adapted by the European Task Force on Atopic Dermatitis. Symptoms present in the first year of life in about 50% of patients, and in 80% by 5 years. Depending upon a patient’s age, the distribution of lesions will vary. The cheeks and extensor surfaces of the arms and legs are typically affected in infants, the flexor surfaces of the arms and legs in the young child, and the flexor surfaces, hands, and feet in the teenage patient and young adult (3). Lesions are erythematous, papulovesicular eruptions, which are sometimes associated with weeping and crusting in early life, and progress to a scaly lichenified eruption with age (4). Most patients have a significant elevation in total serum IgE as well as environmental-and food-specific IgE antibody concentrations (5). A large number of cell types are involved in the pathogenesis of AD, including B cells, T cells, monocytes, macrophages, dendritic cells, eosinophils, platelets, and Langerhans cells (6-8). Early (9) studies showed that the intense pruritus and resultant scratching that develops in patients following exposure to irritants and relevant allergens is an important cause of the physical signs and typical distribution of this disorder.
