Asthma

Asthma is an obstructive airway disorder characterized by reversible airway narrowing, mucus hypersecretion, chronic inflammation, and episodic shortness of breath. Severe recurrent bouts of asthma lead to airway scarring, termed remodeling, which is not reversible and can lead to an increased frequency and severity in asthma exacerbations and lung infections. Asthma can be allergen provoked, which is termed atopic, or asthma may be due to unknown factors and termed intrinsic. There is a broad consensus that the prevalence of asthma has increased dramatically in most industrialized countries over the past several decades, prompting the development of several asthma study cohorts that have attempted to address asthma incidence, etiology, prevention, and control. What has come to be appreciated in the past decade due to the use of conditional gene expression systems, and transgenic animals, is the true complexity of the multiple molecular pathways that are involved in the development and progression of asthma and the understanding that asthma is more accurately characterized as a collection of diseases comprising a syndrome rather than a distinct homogenous entity. Therefore, in terms of a cure, there is no single ‘magic bullet’ with regard to the treatment or the prevention of asthma.