title: Normal host defenses and impairments associated with the delayed resolution of pneumonia.
abstract: The lung is constantly exposed to infectious challenges and depends on a complex system of defense mechanisms to facilitate the clearance of pathogens and prevent the development of infection. Both the upper airway and lower respiratory tract have mechanical, humoral, and cellular mechanisms in place to protect the airways from diverse microorganisms. Impairment in any arm of this system can result in the predisposition of the host to respiratory infections, which may be of a recurrent nature. Defects may be congenital or acquired, and may be iatrogenic in the hospitalized patient. An understanding of these defects may lead to more effective therapies and preventive modalities for decreasing the number and severity of respiratory infections.
authors.affiliation: Department of Pulmonary/Critical Care Medicine, Louisiana State University Medical Center, New Orleans 70112.
authors.forename: C M
authors.initials: CM
authors.lastname: Mason
authors.forename: S
authors.initials: S
authors.lastname: Nelson
mesh_terms: D000375:Aging / Q000276:immunology; D000428:Alcohol Drinking / Q000453:epidemiology; D006801:Humans; D007239:Infections / Q000453:epidemiology; D008168:Lung / Q000276:immunology*; D016676:Macrophages, Alveolar / Q000276:immunology; D011014:Pneumonia / Q000453:epidemiology / Q000276:immunology*; D012008:Recurrence; D012137:Respiratory System / Q000276:immunology; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology