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Urinary tract infections in children: Epidemiology and risk factors

Nader Shaikh, MD
Alejandro Hoberman, MD
Section Editors
Morven S Edwards, MD
Tej K Mattoo, MD, DCH, FRCP
Deputy Editor
Mary M Torchia, MD


Urinary tract infection (UTI) is a common and important clinical problem in childhood. Upper UTIs (ie, acute pyelonephritis) may lead to renal scarring, hypertension, and end-stage renal disease. Although children with pyelonephritis tend to present with fever, it is often difficult on clinical grounds to distinguish cystitis from pyelonephritis, particularly in young children (those younger than two years) [1]. Thus, we have defined UTI broadly here without attempting to distinguish cystitis from pyelonephritis. Acute cystitis in older children is discussed separately. (See "Acute cystitis: Clinical features and diagnosis in children older than two years and adolescents".)

The presence of risk factors for UTI and renal scarring in a child presenting with fever and/or urinary symptoms is helpful in guiding diagnostic testing and management. The epidemiology and risk factors for UTI and renal scarring in children will be reviewed here. Clinical features, diagnosis, and management of UTI, and UTI in newborns (younger than one month of age) are discussed separately. (See "Urinary tract infections in infants and children older than one month: Clinical features and diagnosis" and "Urinary tract infections in infants older than one month and young children: Acute management, imaging, and prognosis" and "Urinary tract infections in children: Long-term management and prevention" and "Urinary tract infections in neonates".)


Prevalence — Awareness of the prevalence of UTI in various subgroups of children enables the clinician to grossly estimate the probability of infection in the patient (ie, the pretest probability) (table 1). This information is important in the evaluation of a child with suspected UTI. (See "Urinary tract infections in infants and children older than one month: Clinical features and diagnosis", section on 'Laboratory evaluation'.)

In young children with fever — The prevalence of UTI in children <2 years presenting with fever has been the subject of several large prospective studies and a meta-analysis (table 1) [2-4]. Important points that emerged from these studies include:

The overall prevalence of UTI is approximately 7 percent in febrile infants and young children but varies by age, race/ethnicity, sex, and circumcision status.

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Literature review current through: Nov 2017. | This topic last updated: May 31, 2017.
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