title: Characteristics of the bladder in infants with urinary tract infections: an ultrasound study.
abstract: BACKGROUND
  Patients with urinary tract infection (UTI) are known to have impaired bladder function as demonstrated by urodynamic (UD) studies. UD is rarely performed in infants.
  
  
  OBJECTIVE
  To evaluate bladder function in infants with UTI using a dynamic US protocol. Maximal bladder volume (MaxBV), residual volume (RV) and bladder wall thickness (BWT) were measured and compared with values from normal controls.
  
  
  METHODS
  A total of 57 consecutive infants (47 males, 10 females; mean age 0.48+/-0.30 years) with proven UTI, and 63 age-matched normal controls (37 males, 26 females; mean age 0.47+/-0.37 years) were recruited. MaxBV was determined just before voiding, and RV and BWT were measured after spontaneous voiding.
  
  
  RESULTS
  Infants with UTI had smaller MaxBV (34.89 vs. 42.91 ml), larger RV (3.46 vs. 1.51 ml) and greater BWT (4.21 vs. 3.68 mm) than normal infants (P<0.05, Mann-Whitney test).
  
  
  CONCLUSIONS
  Smaller bladder volume, larger residual volume and thicker bladder wall in infants with UTI can be explained by bladder instability, hypercontractility and infection-induced oedema of the bladder wall during UTI. The US measurement of bladder parameters might serve as an objective guide for clinical diagnosis and allow objective evaluation of bladder function during posttreatment follow-up.
authors.affiliation: Department of Surgery, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China.
authors.forename: Ji-Xian
authors.initials: JX
authors.lastname: Liu
authors.forename: Vivian Yee-Fong
authors.initials: VY
authors.lastname: Leung
authors.forename: Winnie Chiu-Wing
authors.initials: WC
authors.lastname: Chu
authors.forename: Biji
authors.initials: B
authors.lastname: Sreedhar
authors.forename: Constantine
authors.initials: C
authors.lastname: Metreweli
authors.forename: Chung-Kwong
authors.initials: CK
authors.lastname: Yeung
mesh_terms: D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D018709:Statistics, Nonparametric; D014463:Ultrasonography; D001743:Urinary Bladder / Q000000981:diagnostic imaging* / Q000503:physiopathology; D014552:Urinary Tract Infections / Q000000981:diagnostic imaging* / Q000503:physiopathology; D014563:Urodynamics