Factors Associated with Abnormal Imaging and Infection Recurrence after a First Febrile Urinary Tract Infection in Children.

 We determined factors associated with abnormal imaging and recurrent infections after a first febrile urinary tract infection (UTI) in children younger than 3 years.  We retrospectively reviewed the records of all patients treated at our institute during the years 2000-2009, for a first febrile UTI in children younger than 3 years, who underwent ultrasonography and voiding cystourethrography. We evaluated data regarding factors potentially associated with abnormal ultrasonography and voiding cystourethrography results and recurrence of infections, and formulated a risk score system to assess risk of reflux and high-grade reflux.  There were 282 patients. The only factor predicting abnormal ultrasonogram was non- infection. Risk factors for vesicoureteral reflux included abnormal ultrasonogram, atypical infection, non- infection and infection recurrence. Patients with no identified risk factors for vesicoureteral reflux were unlikely to have high-grade reflux. Higher risk scores were associated with a higher risk for reflux. Non- infection was the only statistically significant predictor of infection recurrence.  All children younger than 3 years with first febrile UTI should undergo ultrasonography. Thereafter, patients with no predictive factors for vesicoureteral reflux may be followed up without further imaging. A non- infection is associated with reflux and infection recurrence.