title: A single-center cohort of Canadian children with VUR reveals renal phenotypes important for genetic studies.
abstract: BACKGROUND
  Many genes and loci have been reported in genetic studies of primary vesicoureteral reflux (VUR), but few have been reproduced in independent cohorts, perhaps because of phenotype heterogeneity. We phenotyped children with VUR who attended urology clinics so we could establish criteria to stratify patients based on the presence or absence of a renal malformation.
  
  
  METHODS
  History, chart review, and DNA were obtained for 200 children with VUR from 189 families to determine the grade of VUR, the mode of presentation, and the family history for each child. Kidney length measured on ultrasound (US) and technetium dimercaptosuccinic acid (DMSA) scans at the time of VUR diagnosis were used to establish the presence of a concurrent renal malformation and identify the presence of renal scarring.
  
  
  RESULTS
  There was an even distribution of girls and boys, and most patients were diagnosed following a urinary tract infection (UTI). Thirty-four percent of the children had severe VUR, and 25 % had undergone surgical correction. VUR is highly heritable, with 15 % of the families reporting multiple affected members. Most patients had normally formed kidneys as determined by US and DMSA imaging. Of the 93 patients who underwent DMSA imaging, 17 (18 %) showed scarring, 2 (2 %) showed scarring and diffuse reduction in uptake, and 13 (14 %) showed an isolated diffuse reduction in uptake.
  
  
  CONCLUSIONS
  Prospective long-term studies of patients with primary VUR combined with renal phenotyping using US and DMSA imaging are needed to establish the presence of a renal malformation. The majority of patients in our study had no renal malformation. This cohort is a new resource for genetic studies of children with primary VUR.
authors.affiliation: Research Institute of McGill University Health Centre, Montreal Children's Hospital, Montréal, Québec, Canada.
authors.forename: Jasmine
authors.initials: J
authors.lastname: El Andalousi
authors.forename: Inga J
authors.initials: IJ
authors.lastname: Murawski
authors.forename: John-Paul
authors.initials: JP
authors.lastname: Capolicchio
authors.forename: Mohamed
authors.initials: M
authors.lastname: El-Sherbiny
authors.forename: Roman
authors.initials: R
authors.lastname: Jednak
authors.forename: Indra R
authors.initials: IR
authors.lastname: Gupta
mesh_terms: D000293:Adolescent; D000375:Aging / Q000502:physiology; D002170:Canada / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004247:DNA / Q000235:genetics; D005006:Ethnicity; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000209:etiology; D007223:Infant; D007231:Infant, Newborn; D007668:Kidney / Q000002:abnormalities / Q000000981:diagnostic imaging; D007677:Kidney Function Tests; D008297:Male; D010641:Phenotype; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012737:Sex Factors; D012959:Socioeconomic Factors; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D014463:Ultrasonography; D014513:Ureter / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000601:surgery; D014718:Vesico-Ureteral Reflux / Q000235:genetics* / Q000473:pathology* / Q000601:surgery
chemical_list: D019275:Radiopharmaceuticals; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D004247:DNA