Diagnosis and Management of the Initial Urinary Tract Infection in Febrile Infants and Young Children 2–24 Months of Age

Publication Date: December 1, 2016
Last Updated: March 14, 2022

Action Statements

1. If a clinician decides that a febrile infant with no apparent source for the fever requires antimicrobial therapy to be administered because of ill appearance or another pressing reason, the clinician should ensure that a urine specimen is obtained for both culture and urinalysis before an antimicrobial is administered; the specimen needs to be obtained through catheterization or suprapubic aspiration (SPA), because the diagnosis of UTI cannot be established reliably through culture of urine collected in a bag. (A, )

2. If a clinician assesses a febrile infant with no apparent source for the fever as not being so ill as to require immediate antimicrobial therapy, then the clinician should assess the likelihood of UTI.
2a. If the clinician determines the febrile infant to have a low likelihood of UTI, then clinical follow-up monitoring without testing is sufficient. (A, )
2b. If the clinician determines that the febrile infant is not in a low-risk group (see below), then there are 2 choices: (A, )
  • Option 1 is to obtain a urine specimen through catheterization or SPA for culture and urinalysis.

  • Option 2 is to obtain a urine specimen through the most convenient means and to perform a urinalysis. If the urinalysis results suggest a UTI (positive leukocyte esterase test results or nitrite test or microscopic analysis results for leukocytes or bacteria), then a urine specimen should be obtained through catheterization or SPA and cultured; if urinalysis of fresh (less than 1 hour since void) urine yields negative leukocyte esterase and nitrite results, then it is reasonable to monitor the clinical course without initiating antimicrobial therapy, recognizing that a negative urinalysis does not rule out a UTI with certainty.


3. To establish the diagnosis of UTI, clinicians should require both urinalysis results that suggest infection (pyuria and/or bacteriuria) and the presence of at least 50,000 colony-forming units (cfu) per milliliter of a uropathogen cultured from a urine specimen obtained through transurethral catheterization or SPA. (C, )

4a. When initiating treatment, the clinician should base the choice of route of administration on practical considerations. Initiating treatment orally or parenterally is equally efficacious. The clinician should base the choice of agent on local antimicrobial sensitivity patterns (if available) and should adjust the choice according to sensitivity testing of the isolated uropathogen. (A, )
4b. The clinician should choose 7 to 14 days as the duration of antimicrobial therapy. (B, )

5. Febrile infants with UTIs should undergo renal and bladder ultrasonography (RBUS). (C, )

6a. Voiding cystourethrography (VCUG) should not be performed routinely after the first febrile UTI. VCUG is indicated if RBUS reveals hydronephrosis, scarring, or other findings that would suggest either high-grade VUR or obstructive uropathy, as well as in other atypical or complex clinical circumstances. (B, )
6b. Further evaluation should be conducted if there is a recurrence of febrile UTI. (X, )

7. After confirmation of UTI, the clinician should instruct parents or guardians to seek prompt medical evaluation (ideally within 48 hours) for future febrile illnesses to ensure that recurrent infections can be detected and treated promptly. (C, )

Recommendation Grading



Diagnosis and Management of the Initial Urinary Tract Infection in Febrile Infants and Young Children 2–24 Months of Age

Authoring Organization

Publication Month/Year

December 1, 2016

Last Updated Month/Year

January 16, 2024

Document Type


External Publication Status


Country of Publication


Document Objectives

To provide an updated review of the supporting evidence on febrile infant and young children with urinary tract infection (UTI) 

Target Patient Population

Urinary Tract Infection in Febrile Infants and Young Children 2–24 Months of Age

Inclusion Criteria

Child, Infant

Health Care Settings

Ambulatory, Hospital, Outpatient

Intended Users

Nurse, nurse practitioner, physician, physician assistant


Assessment and screening, Diagnosis, Management

Diseases/Conditions (MeSH)

D019072 - Antibiotic Prophylaxis, D014552 - Urinary Tract Infections, D005334 - Fever


urinary tract infection (UTI), pediatric, antibiotic, urinary tract infection

Source Citation

Pediatrics December 2016, 138 (6) e20163026; DOI: https://doi.org/10.1542/peds.2016-3026