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Fever of unknown origin in children: Evaluation

Debra L Palazzi, MD, MEd
Section Editors
Sheldon L Kaplan, MD
Robert Sundel, MD
Jan E Drutz, MD
Deputy Editor
Mary M Torchia, MD


Fever is a common presenting complaint in children. Most febrile illnesses either resolve before a diagnosis can be made or develop distinguishing characteristics that lead to a diagnosis. Fever of unknown origin (FUO) refers to a prolonged febrile illness without an established etiology despite thorough evaluation.

An approach to the evaluation of FUO in children will be reviewed here. Causes of FUO in children, fever without a source, and fever in specific pediatric populations are discussed separately:

(See "Fever of unknown origin in children: Etiology".)

(See "Fever without a source in children 3 to 36 months of age".)

(See "Febrile infant (younger than 90 days of age): Outpatient evaluation" and "Febrile infant (younger than 90 days of age): Management".)

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