title: Ultrasound as a screening test for genitourinary anomalies in children with UTI.
abstract: BACKGROUND
  The 2011 American Academy of Pediatrics guidelines state that renal and bladder ultrasound (RBUS) should be performed after initial febrile urinary tract infection (UTI) in a young child, with voiding cystourethrogram (VCUG) performed only if RBUS shows abnormalities. We sought to determine test characteristics and predictive values of RBUS for VCUG findings in this setting.
  
  
  METHODS
  We analyzed 3995 clinical encounters from January 1, 2006 to December 31, 2010 during which VCUG and RBUS were performed for history of UTI. Patients who had previous postnatal genitourinary imaging or history of prenatal hydronephrosis were excluded. Sensitivity, specificity, and predictive values of RBUS for VCUG abnormalities were determined.
  
  
  RESULTS
  We identified 2259 patients age <60 months who had UTI as the indication for imaging. RBUS was reported as "normal" in 75%. On VCUG, any vesicoureteral reflux (VUR) was identified in 41.7%, VUR grade >II in 20.9%, and VUR grade >III in 2.8%. Sensitivity of RBUS for any abnormal findings on VCUG ranged from 5% (specificity: 97%) to 28% (specificity: 77%). Sensitivity for VUR grade >III ranged from 18% (specificity: 97%) to 55% (specificity: 77%). Among the 1203 children aged 2 to 24 months imaged after a first febrile UTI, positive predictive value of RBUS was 37% to 47% for VUR grade >II (13% to 24% for VUR grade >III); negative predictive value was 72% to 74% for VUR grade >II (95% to 96% for VUR grade >III).
  
  
  CONCLUSIONS
  RBUS is a poor screening test for genitourinary abnormalities. RBUS and VCUG should be considered complementary as they provide important, but different, information.
authors: Department of Urology;
authors: Caleb P
authors: CP
authors: Nelson
authors: Emilie K
authors: EK
authors: Johnson
authors: Tanya
authors: T
authors: Logvinenko
authors: Jeanne S
authors: JS
authors: Chow
mesh_terms: D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008403:Mass Screening / Q000379:methods / Q000592:standards*; D014463:Ultrasonography; D014552:Urinary Tract Infections / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D014564:Urogenital Abnormalities / Q000000981:diagnostic imaging* / Q000453:epidemiology*
keywords: imaging; pediatrics; urinary tract infection; vesicoureteral reflux