Purpose <p>Additional evaluation after pediatric febrile urinary tract infection (UTI) is required to identify children at risk of long-term renal complications. Because these complications are difficult to directly assess in clinical practice, we sought to identify clinical predictors that may guide additional evaluation, using subsequent intervention as a pragmatic indicator of clinically significant urological concern following a first febrile UTI.</p> Methods <p>We retrospectively reviewed 2,155 children aged &lt; 10&#xa0;years with a first febrile UTI. Clinical factors at diagnosis were analyzed to identify predictors associated with subsequent intervention. The sensitivity and specificity of renal and bladder ultrasonography (RBUS) for predicting subsequent intervention were evaluated when performed universally or selectively according to these predictors.</p> Results <p>Of the 2,155 children, 88 (4.1%) subsequently underwent intervention, including continuous antibiotic prophylaxis in 40 and surgical procedures in 48. Hospitalization or antibiotic use within the preceding month (p &lt; 0.001), age ≥ 24&#xa0;months (p &lt; 0.001), infection with a non-<i>E.coli</i> pathogen (p &lt; 0.001), failure to achieve defervescence ≤ 2&#xa0;days after antibiotic therapy (p = 0.038), and peak body temperature &gt; 39.0 ℃ (p = 0.007) were independently associated with subsequent intervention. Among the 2,047 children who underwent RBUS, 993 (48.5%) had at least one identified risk factor. Universal (n = 2,047) and selective (n = 993) RBUS demonstrated similar sensitivity and specificity for identifying children requiring intervention, while selective use reduced RBUS utilization by 51.5%.</p> Conclusion <p>Clinical factors identified at diagnosis may help guide selective additional evaluation in children after their first febrile UTI.</p>