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Diagnostic approach to community-acquired pneumonia in adults

John G Bartlett, MD
Section Editor
Stephen B Calderwood, MD
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. 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 diagnostic approach to CAP in immunocompetent adults will be reviewed here. A variety of other important issues related to CAP are discussed separately. These include:

The epidemiology and microbiology of CAP (see "Epidemiology, pathogenesis, and microbiology of 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")

The approach to patients with nonresolving pneumonia (see "Nonresolving pneumonia")

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Literature review current through: Nov 2017. | This topic last updated: Jul 13, 2017.
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