How Well Does Urinalysis Perform in Diagnosing Urinary Tract Infection in Young Infants?

Urinalysis has shown variable performance as a screening test for urinary tract infection (UTI) in young febrile infants, particularly those aged <60 days. The current guidelines from the American Academy of Pediatrics define UTI for infants aged >2 months as the presence of pyuria and a urinary bacterial colony count of >50,000 colony-forming units (CFUs)/mL. Criteria for infants younger than 2 months are not established.

As part of a larger cross-sectional study in febrile infants aged ≤60 days presenting to emergency departments across the U.S., researchers assessed the performance of urinalysis in detecting UTI (defined as a urine culture obtained by catheterization with growth ≥50,000 CFUs/mL). Results were as follows:

• In over 4000 infan…