Febrile urinary tract infection, vesicoureteral reflux, and renal scarring: current controversies in approach to evaluation.

The ideal approach to the radiological evaluation of children with urinary tract infection (UTI) is in a state of confusion. The conventional bottom-up approach, with its focus on the detection of upper and lower urinary tract abnormalities, including vesicoureteral reflux, has been challenged by the top-down approach, which focuses on confirming the diagnosis of acute pyelonephritis before more invasive imaging is considered. Controversies abound regarding which approach may best assess the ultimate risk for reflux-related renal scarring. Evolving practices motivated by the emerging evidence, the desire to minimize unnecessary interventions, as well as improve compliance with recommended testing, have added to the current controversies. Recent guideline updates and ongoing clinical trials hopefully will help in addressing some of these concerns.