Asthma: pathology and pathophysiology.

CONTEXT: Asthma has been defined as a chronic inflammatory disorder of the airways that is associated with recruitment of inflammatory cells and the clinical development of wheezing, shortness of breath, chest tightness, and cough. Asthma is a major public health issue. It affects 5% of the United States population and accounts for 2 million emergency department visits, 470,000 hospitalizations, and 4500 deaths annually.

OBJECTIVE

To review the pathophysiology and characteristic pathologic patterns of this disease and discuss the possible mechanisms of production of the lesions.

DATA SOURCES: We searched the literature using MEDLINE and OVID. We also searched related conference abstracts and bibliographies of selected studies.

CONCLUSIONS

There has been a significant evolution in our understanding of asthma. Specific pathways and mechanisms in recent years have been studied; however, numerous mediators and cell receptors have raised new questions that remain to be answered.