Neutrophils in asthma.

Asthma is a complex disease with a significant inflammatory component. Multiple cell types are involved in its pathophysiology. The presence of eosinophils, the cell usually associated with allergic diseases, does not fully explain the inflammation found in asthma.

Infectious triggers of asthma.

There is abundant evidence that asthma is frequently exacerbated by infectious agents. Several viruses have been implicated in the inception and exacerbation of asthma. Recent attention has been directed at the role of infections with the atypical bacteria Mycoplasma pneumoniae and Chlamydia pneumoniae as agents capable of triggering asthma exacerbations and potentially as inciting agents for asthma.