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Clinical manifestations and diagnosis of Legionella infection

Victor L Yu, MD
Janet E Stout, PhD
Nieves Sopena Galindo, MD
Section Editor
Stephen B Calderwood, MD
Deputy Editor
Sheila Bond, MD


Since the organism was first recognized in 1976 during an outbreak at an American Legion Convention in Philadelphia, Legionella has been identified as a relatively common cause of both community-acquired and hospital-acquired pneumonia.

Legionellosis refers to the two clinical syndromes caused by bacteria of the genus Legionella:

Legionnaires' disease is the more common syndrome of pneumonia caused by Legionella species

Pontiac fever is an acute, febrile, self-limited illness that has been linked to Legionella species

The clinical manifestations and diagnosis of Legionella infection will be reviewed here. The epidemiology, pathogenesis, treatment, and prevention of this entity are discussed separately. (See "Epidemiology and pathogenesis of Legionella infection" and "Treatment and prevention of Legionella infection".)

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Literature review current through: Nov 2017. | This topic last updated: Apr 07, 2016.
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