How is atopy (type I HS immediate)?

➢ Type I HS include atopic diseases, which are an exaggerated IgE mediated immune responses (i.e., allergic: asthma, rhinitis, conjunctivitis, and dermatitis), and allergic diseases, which are immune responses to foreign allergens (i.e., anaphylaxis, urticaria, angioedema, food, and drug allergies). ➢ Atopy is defined as “a genetic predisposition toward the development of immediate HS reactions (to make IgE) against common environmental antigens (allergen)”. ➢ There are certain risk factors that increase the risk of allergic diseases. These factors include geographical distribution, environmental risks such as pollution or socioeconomic status, genetic predisposition, or the “hygiene hypothesis”. ➢ Hygiene hypothesis proposes that childhood exposure to antigens from a diverse range of microbes leads to a better-functioning immune system later in life. ➢ The lack of early challenges to the immune system by organisms may result in failures in immune system functioning later in life