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Pneumonia caused by Chlamydia pneumoniae in adults

Dori F Zaleznik, MD
Margaret R Hammerschlag, MD
Section Editors
John G Bartlett, MD
Thomas M File, Jr, MD
Deputy Editor
Sheila Bond, MD


Chlamydia pneumoniae is an obligate intracellular bacterium that causes respiratory tract infections including pharyngitis, bronchitis, and pneumonia. Pneumonia caused by C. pneumoniae is typically community acquired and mild.

Pneumonia caused by C. pneumoniae in adults will be discussed here. Pneumonia caused by Chlamydia psittaci, a related zoonotic bacterium that can also cause respiratory infections in humans, is discussed separately (see "Psittacosis" and "Pneumonia caused by Chlamydia species in children"). Pneumonia due to Chlamydia trachomatis, which is most often seen in neonates, is discussed separately. (See "Chlamydia trachomatis infections in the newborn".)

The epidemiology, clinical features, diagnosis and management of community-acquired pneumonia are discussed separately:

(See "Epidemiology, pathogenesis, and microbiology of community-acquired pneumonia in adults".)

(See "Diagnostic approach to community-acquired pneumonia in adults".)

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Literature review current through: Nov 2017. | This topic last updated: Nov 29, 2017.
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