title: Does the presence of vesicoureteral reflux affect in vitro uropathogenic E. coli growth rate in urine?
abstract: BACKGROUND
  Uroepithelial molecules like uroplakins are involved both in the development of urinary tract and in colonization, attachment and invasion of uropathogenic Escherichia coli (UPEC). Uroplakin disorders are also associated with vesicoureteral reflux (VUR). We hypothesized that urine contents, as well as urinary flow, may be altered in VUR, and aimed to determine whether in vitro UPEC growth is increased in urine from the refluxing systems.
  
  
  METHODS
  Children evaluated by voiding cystourethrography for UTI were enrolled. Groups 1 and 2 included children with and without VUR, respectively. Sterile urine samples were obtained from all patients, and 2 × 10(2) cfu/mL UPEC suspension was inoculated into these samples. After incubation for 24 h, colony counts were assessed. Both groups were compared for UPEC growth and colony counts.
  
  
  RESULTS
  Forty-two urine samples were included (21 in each group). UPEC was cultured in 9 (43 %) and 3 (14 %) samples in Groups 1 and 2, respectively (p = 0.040, OR 4.5). Colony counts were similar in both groups (log x; 2.36 ± 0.25 vs. 2.37 ± 0.12, p = 0.923).
  
  
  CONCLUSIONS
  Inoculation of 2 × 10(2) cfu UPEC resulted in growth in almost half of the urine samples from refluxing systems, while UPEC growth was inhibited in most urine samples from non-refluxing systems suggesting that urine contents in refluxing units change in such a way that UPEC growth is facilitated.
authors.affiliation: Dokuz Eylül University Medical Faculty, Balçova 35340, İzmir, Turkey. alper.soylu@deu.edu.tr.
authors.forename: Alper
authors.initials: A
authors.lastname: Soylu
authors.affiliation: Dokuz Eylül University Medical Faculty, Balçova 35340, İzmir, Turkey.
authors.forename: Meral
authors.initials: M
authors.lastname: Karaman
authors.affiliation: Dokuz Eylül University Medical Faculty, Balçova 35340, İzmir, Turkey.
authors.forename: Demet
authors.initials: D
authors.lastname: Alaygut
authors.affiliation: Dokuz Eylül University Medical Faculty, Balçova 35340, İzmir, Turkey.
authors.forename: Seçil Arslansoyu
authors.initials: SA
authors.lastname: Çamlar
authors.affiliation: Dokuz Eylül University Medical Faculty, Balçova 35340, İzmir, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Türkmen
authors.affiliation: Dokuz Eylül University Medical Faculty, Balçova 35340, İzmir, Turkey.
authors.forename: Salih
authors.initials: S
authors.lastname: Kavukçu
mesh_terms: D002675:Child, Preschool; D004927:Escherichia coli Infections / Q000209:etiology / Q000382:microbiology* / Q000652:urine; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D008297:Male; D012008:Recurrence; D016482:Urinalysis; D014552:Urinary Tract Infections / Q000209:etiology / Q000382:microbiology* / Q000652:urine; D056689:Uropathogenic Escherichia coli / Q000302:isolation & purification*; D019459:Urothelium / Q000382:microbiology / Q000473:pathology; D014718:Vesico-Ureteral Reflux / Q000150:complications* / Q000473:pathology
keywords: Growth rate; Urine; Uropathogenic Escherichia coli; Vesicoureteral reflux