title: Prevalence of upper urinary tract anomalies in hospitalized premature infants with urinary tract infection.
abstract: OBJECTIVE
  The 2011 American Academy of Pediatrics (AAP) guidelines address imaging after initial febrile urinary tract infection (UTI) in infants >2 months of age. We sought to determine the frequency of upper urinary tract anomalies (hydronephrosis and vesicoureteral reflux (VUR)) in hospitalized premature infants with UTI.
  
  
  METHODS
  We retrospectively reviewed the electronic medical records of neonatal intensive care unit (NICU) admissions at a tertiary care children's hospital between 1 January 2006 and 31 December 2010. We queried the records for UTI, renal ultrasound (US) and voiding cystourethrogram (VCUG).
  
  
  RESULTS
  We identified 3518 unique admissions. UTI occurred in 118 infants (3%). Sixty-nine (60%) had a normal US. Renal dilation was predominantly renal pelvic dilation (12%) and isolated caliectasis (22%). VUR was identified in 15 (14%) infants evaluated with a VCUG. VUR was identified in nine (12%) infants without and in seven (16%) with an abnormality on US. Reflux was identified in 7% of male and 38% of female infants with a UTI.
  
  
  CONCLUSIONS
  Anatomic abnormalities of the upper urinary tract are uncommon in premature infants with a UTI that occurs during neonatal hospitalization. In concordance with the AAP guidelines, a VCUG may not be required in all NICU infants under age 2 months after a single UTI.
authors.affiliation: Division of Newborn Medicine, Department of Pediatrics, Washington University School of Medicine and St Louis Children's Hospital, Saint Louis, MO, USA.
authors.forename: A
authors.initials: A
authors.lastname: Vachharajani
authors.affiliation: Division of Urology, Department of Surgery, Washington University School of Medicine and St Louis Children's Hospital, Saint Louis, MO, USA.
authors.forename: G J
authors.initials: GJ
authors.lastname: Vricella
authors.affiliation: Division of Newborn Medicine, Department of Pediatrics, Washington University School of Medicine and St Louis Children's Hospital, Saint Louis, MO, USA.
authors.forename: T
authors.initials: T
authors.lastname: Najaf
authors.affiliation: Division of Urology, Department of Surgery, Washington University School of Medicine and St Louis Children's Hospital, Saint Louis, MO, USA.
authors.forename: D E
authors.initials: DE
authors.lastname: Coplen
mesh_terms: D057286:Electronic Health Records; D005260:Female; D006801:Humans; D006869:Hydronephrosis / Q000175:diagnosis*; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D017410:Practice Guidelines as Topic; D012189:Retrospective Studies; D062606:Tertiary Care Centers; D014463:Ultrasonography; D014551:Urinary Tract / Q000002:abnormalities / Q000000981:diagnostic imaging*; D014552:Urinary Tract Infections / Q000150:complications* / Q000453:epidemiology*; D014567:Urography; D014718:Vesico-Ureteral Reflux / Q000175:diagnosis*