title: Maximal kidney length predicts need for native nephrectomy in ADPKD patients undergoing renal transplantation.
abstract: BACKGROUND
  Native nephrectomy in patients with autosomal dominant polycystic kidney disease (ADPKD) is performed on a case-by-case basis. We determine if pre-transplant maximal kidney length (MKL) can be used to predict ultimate nephrectomy status.
  
  
  METHODS
  We performed a retrospective review of ADPKD patients who underwent renal transplantation at our centre between January 2000 and December 2012. Pre-transplant measurements of MKL alone, MKL adjusted for height (HtMKL), weight (WtMKL) and body mass index (BMI-MKL) were each assessed for their predictive ability via a receiver operating characteristic (ROC) curve analysis.
  
  
  RESULTS
  In total, 84 patients met our inclusion criteria, of which 17 (20.2%) underwent native nephrectomy. An MKL ROC curve analysis revealed an area under the curve (AUC) of 0.867 (95% confidence interval [CI] 0.775-0.931; p < 0.001). An optimal cutoff criterion of >21.5 cm revealed a sensitivity of 94.1% (95% CI 71.3-99.9) and specificity of 70.1% (95% CI 57.7-80.7) for eventual nephrectomy. The AUC of HtMKL, WtMKL and BMI-MKL ROC curves did not differ significantly from MKL alone. HtMKL improved specificity, but not overall test performance. The determination of the cut-off MKL may be influenced by the single-centre retrospective nature of this analysis, as well as the fact that renal size was determined by ultrasound and not computerized tomography or magnetic resonance imaging.
  
  
  CONCLUSIONS
  MKL in patients with ADPKD is associated with the eventual need for nephrectomy and may be a useful clinical tool to risk stratify these patients and therefore guide patient conversations to a decision to leave the native kidneys in situ.
authors.affiliation: Schulich School of Medicine & Dentistry, Western University, London, ON;
authors.forename: Octav
authors.initials: O
authors.lastname: Cristea
authors.affiliation: Department of Surgery, Division of Urology, Western University, London, ON;
authors.forename: Daniel
authors.initials: D
authors.lastname: Yanko
authors.affiliation: Department of Surgery, Division of Urology, Western University, London, ON;
authors.forename: Sarah
authors.initials: S
authors.lastname: Felbel
authors.affiliation: Department of Medicine, Division of Nephrology, Western University, London, ON.
authors.forename: Andrew
authors.initials: A
authors.lastname: House
authors.affiliation: Schulich School of Medicine & Dentistry, Western University, London, ON; ; Department of Surgery, Division of Urology, Western University, London, ON; ; Multi-Organ Transplant Program, London Health Sciences Centre, Western University, London, ON; ; Matthew Mailing Centre for Translational Transplant Studies, London Health Sciences Centre, Western University, London, ON;
authors.forename: Alp
authors.initials: A
authors.lastname: Sener
authors.affiliation: Schulich School of Medicine & Dentistry, Western University, London, ON; ; Department of Surgery, Division of Urology, Western University, London, ON; ; Multi-Organ Transplant Program, London Health Sciences Centre, Western University, London, ON; ; Matthew Mailing Centre for Translational Transplant Studies, London Health Sciences Centre, Western University, London, ON;
authors.forename: Patrick P W
authors.initials: PP
authors.lastname: Luke