Antimicrobial prophylaxis to prevent febrile recurrent urinary tract infection in infants aged 2 months to 2 years without vesicoureteral reflux or with grade I to IV VUR is not supported by currently available data, and therefore voiding cystourethrography to detect VUR should no longer be used routinely after a first UTI in this population, according to a newly updated American Academy of Pediatrics practice guideline.
The update – the first since 1999 to the guideline regarding the diagnosis and management of the initial UTI in febrile infants and young children – is published in the Aug. 29 issue of Pediatrics (2011;128:595-610 [doi:10.1542/peds.2011-1330]).
The previous guideline included strong encouragement of imaging studies despite insufficient evidence supporting a routine voiding cystourethrogram (VCUG), but the "position of the current subcommittee reflects the new evidence demonstrating antimicrobial prophylaxis not to be effective as presumed previously. Moreover, prompt diagnosis and effective treatment of a febrile UTI recurrence may be of greater importance regardless of whether VUR is present or the child is receiving antimicrobial prophylaxis," according to the AAP Subcommittee on Urinary Tract Infection, which authored the updated guideline.
The update, which is intended for use in various clinical settings including offices, hospitals, and emergency departments for the diagnosis and management of the approximately 5% of children in this age group who are affected by UTIs, is based in large part on new data regarding imaging and diagnostic criteria in this population.
It also includes changes as to which children should undergo urine testing, how the sample should be obtained, and how treatment and follow-up should be conducted in those found to have a UTI, according to lead author Dr. Kenneth B. Roberts of Greensboro, N.C., and his subcommittee colleagues.
The "long-awaited update" provides an "exceptionally evidence-based guideline that differs in important ways from the 1999 guidelines and sets a high standard for transparency and scholarship," Dr. Thomas B. Newman of the University of California, San Francisco, wrote in an accompanying editorial (Pediatrics 2011;128:572-75 [doi:10.1542/peds.2011-1818]).
Dr. Newman also said that the guideline and a technical report containing the data on which the recommendations are based represent "a significant advance."
The guideline includes seven recommendations or action statements:
• Action Statement 1. It calls for obtaining a urine specimen for both culture and urinalysis prior to administration of an antimicrobial agent in infants with no apparent source for their fever, and in whom the clinician decides antimicrobial therapy should be administered due to ill appearance or another pressing reason. Since they assert that the diagnosis of UTI cannot be reliably established through culture of urine collected in a bag, the subcommittee says the specimen should be obtained through catheterization or suprapubic aspirate (SPA). The evidence quality for this "strong recommendation" was level A, meaning it is based on well-designed randomized controlled trials or diagnostic studies of relevant populations.
Although catheterization is invasive, the subcommittee determined that the risks of this approach are outweighed by the potential benefit of diagnosing a UTI and treating it appropriately before renal scarring occurs, and, conversely, by avoiding overtreatment and unnecessary and expensive imaging.
• Action Statements 2a and 2b. These also represent "strong recommendations" based on level A evidence, but address those febrile infants who the clinician does not feel require immediate antimicrobial therapy. In these infants, the clinician should assess whether the likelihood of UTI is low or high. Those with a low likelihood of UTI (such as those with another obvious infection, which reduces the likelihood of UTI) can undergo clinical follow-up monitoring without testing; those not in a low-risk group (such as girls and uncircumcised boys, who have a higher risk for UTI) can be managed either by obtaining a urine specimen via catheterization or SPA for culture and urinalysis, or by the most convenient means for urinalysis. If the urinalysis results suggest a UTI, a specimen should then be obtained by catheterization or SPA for culture.
A negative urinalysis, however, suggests it is reasonable to monitor the clinical course without initiating antimicrobial therapy.
• Action Statement 3. This also addresses UTI diagnosis, and states that clinicians should require both urinalysis results that suggest infection (pyuria and/or bacteriuria) and the presence of at least 50,000 colony-forming units per milliliter of a uropathogen cultured from a specimen obtained via catheterization or SPA. Unlike the first two action statements, this one is based on observational studies, and thus is considered level C evidence and represents a "recommendation" rather than a "strong recommendation."
"These criteria reduce the likelihood of overdiagnosis of UTI in infants with asymptomatic bacteriuria or contaminated specimens," the subcommittee wrote.