Urinary tract infections in children: Defining the problem Pediatric urinary tract infection (UTI) is one of the most common childhood infections constituting an area of concern for parents and clinicians alike.1,2 Girls are more likely to be diagnosed with a UTI while about half the boys with UTI are likely to be diagnosed within the first 12 months of life. Prevalence and incidence further varies by age, race/ ethnicity, sex and circumcision status.2 Children frequently present with complaints of fever, lethargy, anorexia, and vomiting, but UTIs may have several adverse consequences as well, especially in the young.1,3 Susceptibility to UTIs in this vulnerable population has been attributed to an array of causes, with vesicoureteral reflux (VUR) being the most frequent (Figure 1).4 The infection may affect the upper urinary tract (pyelonephritis) or the lower urinary tract (cystitis), although clinical distinction based on symptoms and signs is difficult, especially in infants and young children.