ABSTRACT
Asthma is a chronic disease of the airways in which airway inflammation is considered to play a major role in its development in the majority of asthma sufferers. The type and severity of asthma symptoms can also vary from an individual to another. For example, some will only have a cough (called cough variant of asthma), although an isolated cough is often due to upper airway cough syndrome (UACS) or gastroesophageal reflux disease (GERD), or only report effort intolerance while others have many symptoms. Asthma most often begins in childhood and is associated with atopy, following sensitization to common allergens. Almost all children developing asthma after the age of 6 are atopic. The physiological manifestations of asthma such as airway hyperresponsiveness (AHR), variable airway obstruction, mucus hypersecretion, and airway remodeling seem to result from the activation of innate and adaptive immune systems and their interaction with epithelial cells.
