title: Unilateral duplicated system: comparative length and function of the kidneys.
abstract: OBJECTIVE
  The objective of this study was to estimate kidney length and function in patients with unilateral duplex kidney.
  
  
  METHODS
  Thirteen patients with a unilateral duplicated system were reviewed retrospectively. The length of the kidneys was measured by ultrasound, and the relative function of the kidneys was estimated by renal scan.
  
  
  RESULTS
  In all patients, the duplex kidney was the left one. The length of the right kidney on the renal ultrasound growth chart was from -1.5 to +0.4 standard deviations from the mean for age, and the left kidney length was from -0.5 to +4.3 standard deviations from the mean. On renal scans the kidneys with a duplicated system contributed 51 to 67% to total renal function; the contralateral ones, 33 to 49%.
  
  
  CONCLUSIONS
  Kidneys with a duplicated system may be larger than their counterparts and they may contribute more to total renal function. When a disparity in length between the 2 kidneys is encountered, 1 of the possibilities that should be taken into account is a unilateral duplicated system.
authors.affiliation: Department of Nephrology, Schneider Children's Medical Center of Israel, Petah Tiqva. mdavidovits@clalit.org.il.
authors.forename: Miriam
authors.initials: M
authors.lastname: Davidovits
authors.forename: Bella
authors.initials: B
authors.lastname: Eisenstein
authors.forename: Niza
authors.initials: N
authors.lastname: Ziv
authors.forename: Irit
authors.initials: I
authors.lastname: Krause
authors.forename: Roxanna
authors.initials: R
authors.lastname: Cleper
authors.forename: Zvi
authors.initials: Z
authors.lastname: Bar-Sever
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007668:Kidney / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000473:pathology; D007674:Kidney Diseases / Q000175:diagnosis* / Q000473:pathology; D007677:Kidney Function Tests; D008297:Male; D009929:Organ Size; D011877:Radionuclide Imaging; D012189:Retrospective Studies; D014463:Ultrasonography