title: Significance of preimplantation analysis of kidney biopsies from expanded criteria donors in long-term outcome.
abstract: BACKGROUND
  The shortage of organs has led to expanding the criteria for donors. Histologic evaluations before transplantation may enable the identification of organs unsuitable for single implantation. The aim of this study was to evaluate the histologic findings as prognostic factors of allograft survival from expanded criteria donors (ECDs).
  
  
  METHODS
  We included a cohort of 136 single transplantations with kidneys from ECD and correlated the preimplantation pathologic findings with graft failure. Renal structures from ECD older (n=104) or younger (n=32) than 60 years were evaluated histologically for renal senescence and rated with a total histologic score. A multivariate Cox analysis was performed to identify predictors of graft failure.
  
  
  RESULTS
  Glomerulosclerosis was the most prevalent lesion in biopsies from donors older and younger than 60 years (P=0.002); interstitial fibrosis was more severe in biopsies from older donors (P=0.001); older donors showed a higher prevalence of tubular atrophy (P=0.022), and vascular compartment showed no significant differences. Kidney biopsy-based scoring system ranged from 0 to 15 points, indicating the presence of changes in the renal parenchyma. Biopsies with total histologic scores less than or equal to 5 showed significantly better 5-year graft survival than those with scores more than 5 (P<0.001). A preimplantation score more than 5 points remained an independent predictor of graft failure (hazard ratio 6.95; 95% confidence interval 1.57-30).
  
  
  CONCLUSIONS
  Histologic analysis of kidney biopsies before transplantation is a valuable tool for facilitating the selection of viable grafts from ECD donors. When the total score is more than 5, single kidney transplantation from ECD should not be recommended for patients similar to this study population.
authors.affiliation: Servicio de Nefrología, Hospital Universitario Reina Sofía, Córdoba, Spain. mariad.navarro.sspa@juntadeandalucia.es
authors.forename: María Dolores
authors.initials: MD
authors.lastname: Navarro
authors.forename: María
authors.initials: M
authors.lastname: López-Andréu
authors.forename: Alberto
authors.initials: A
authors.lastname: Rodríguez-Benot
authors.forename: Rosa
authors.initials: R
authors.lastname: Ortega-Salas
authors.forename: María Luisa Agüera
authors.initials: ML
authors.lastname: Morales
authors.forename: Fernando
authors.initials: F
authors.lastname: López-Rubio
authors.forename: Pedro Aljama
authors.initials: PA
authors.lastname: García
mesh_terms: D000368:Aged; D001706:Biopsy; D015331:Cohort Studies; D005260:Female; D005355:Fibrosis; D005921:Glomerulonephritis / Q000473:pathology; D006085:Graft Survival; D006801:Humans; D007668:Kidney / Q000473:pathology*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012720:Severity of Illness Index; D014019:Tissue Donors; D009927:Tissue and Organ Procurement; D016896:Treatment Outcome