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Epidemiology, pathogenesis, and microbiology of community-acquired pneumonia in adults

Thomas J Marrie, MD
Thomas M File, Jr, MD
Section Editors
John G Bartlett, MD
Julio A Ramirez, MD, FACP
Deputy Editor
Sheila Bond, MD


Community-acquired pneumonia (CAP) is defined as an acute infection of the pulmonary parenchyma in a patient who has acquired the infection in the community, as distinguished from hospital-acquired (nosocomial) pneumonia (HAP).

CAP is a common and potentially serious illness [1-3]. It is associated with considerable morbidity and mortality, particularly in older adult patients and those with significant comorbidities. (See "Prognosis of community-acquired pneumonia in adults".)

The epidemiology, pathogenesis, and microbiology of CAP in adults will be reviewed here. A variety of other important issues related to CAP are discussed separately. These include:

The diagnostic approach to patients with CAP (see "Diagnostic approach to community-acquired pneumonia in adults")

The use of sputum cultures for the evaluation of bacterial pneumonia (see "Sputum cultures for the evaluation of bacterial pneumonia")

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Literature review current through: Nov 2017. | This topic last updated: Feb 01, 2017.
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