Is Renal Ultrasound After First UTI Necessary?

Some research suggests that renal ultrasound is not warranted after a first urinary tract infection (UTI) in young infants if their prenatal ultrasounds were normal (Journal Watch Pediatrics and Adolescent Medicine Feb 10 2003). To evaluate the concordance between prenatal renal ultrasound (RUS) and post-UTI RUS, Israeli physicians prospectively compared 209 children (age, ≤5 years) who were hospitalized with first simple UTIs.

Complete concordance of prenatal and post-UTI RUS findings occurred in 96% of cases. In only one patient with a normal prenatal RUS did the post-UTI examination reveal new abnormal findings that affected management. Even in that patient, no therapy was required for the anomaly. Seven children with normal prenatal RUSs had abnormal post-UTI findings. Children with normal prenatal RUSs were 17 times more likely to have normal post-UTI RUS findings than were children with abnormal prenatal RUSs. Six of the nine patients with abnormal post-UTI RUSs had vesicoureteral reflux. The predictive value of a normal prenatal RUS for predicting a normal post-UTI voiding cystourethrogram was 73%.