The links between allergen skin test sensitivity, airway responsiveness and airway response to allergen

Background: The allergen‐induced early asthmatic response [provocation concentration (PC) 20 , the concentration causing a 20% forced expiratory volume in 1 s (FEV) 1 fall] depends on the level of IgE sensitivity and the degree of nonallergic airway hyperresponsiveness (AHR) and can be predicted from histamine PC 20 and allergen skin test endpoint. Objectives: We examined the relationships between allergen PC 20 , methacholine PC 20 , and...