title: Elevated postvoid residual urine volume predicting recurrence of urinary tract infections in toilet-trained children.
abstract: BACKGROUND
  The aim of this study was to examine whether toilet-trained children with a history of febrile urinary tract infection (fUTI) and elevated postvoid residual (PVR) urine volume according to a recently published PVR nomogram were at greater risk of UTI recurrence.
  
  
  METHODS
  One month after recovery from febrile UTI, constipation was diagnosed according to the Rome III criteria, and lower urinary tract (LUT) function was evaluated with two sets of uroflowmetry and PVR by ultrasonography. For children aged ≦ 6 and ≧ 7 years, elevated PVR is defined as >20 and >10 ml, respectively. Cox proportion hazards regression was used to evaluate the risk factors for recurrence of UTI.
  
  
  RESULTS
  Between 2005 and 2011, 60 children aged 6.5 ± 2.5 years (boy:girl ratio 27:33) were enrolled for analysis. Univariate analysis showed that recurrent febrile UTI was more commonly observed in children with elevated PVR [repetitive elevated PVR: hazard ratio (HR) 5.75, 95% confidence interval (CI) 1.41-23.4; one elevated PVR: HR 4.53, 95% CI 1.01-20.2] and high-grade vesicoureteral reflux (VUR; HR 4.53, 95% CI 1.46-14.07). Multivariate analysis showed that younger age (HR 1.37, 95% CI 1.03-1.82, p < 0.01) and elevated PVR (HR 2.88, 95% CI 1.44-5.73, p = 0.01) were significant, independent risk factors for recurrent febrile UTI--but not gender, presence of high-grade VUR and constipation.
  
  
  CONCLUSIONS
  Elevated PVR defined by the new PVR nomogram predicted recurrent UTI in children with history of febrile UTI. Care should be taken to manage children with elevated PVR.
authors: Division of Urology, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, 16F, 289 Chienkuo Road, Xindian, New Taipei, 231, Taiwan.
authors: Shang-Jen
authors: SJ
authors: Chang
authors: Li-Ping
authors: LP
authors: Tsai
authors: Chun-Kai
authors: CK
authors: Hsu
authors: Stephen S
authors: SS
authors: Yang
mesh_terms: D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003248:Constipation / Q000150:complications / Q000453:epidemiology; D003556:Cystitis / Q000453:epidemiology / Q000209:etiology; D005260:Female; D005334:Fever / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D015994:Incidence; D059411:Lower Urinary Tract Symptoms / Q000453:epidemiology / Q000652:urine; D008297:Male; D011237:Predictive Value of Tests; D012008:Recurrence; D012307:Risk Factors; D012737:Sex Factors; D014039:Toilet Training; D014552:Urinary Tract Infections / Q000453:epidemiology / Q000652:urine*; D014563:Urodynamics; D014718:Vesico-Ureteral Reflux / Q000150:complications