title: Measurement of chronic damage in the donor kidney and graft survival.
abstract: BACKGROUND
  So-called marginal kidneys are used increasingly in renal transplantation, but features of marginal kidneys are disputed.
  
  
  METHODS
  To help define marginal, a morphometric measure, the index of chronic damage, was applied retrospectively to 500 implantation biopsy specimens of cadaveric grafts, and death-censored graft survival was calculated, up to 14 years after transplantation.
  
  
  RESULTS
  An index of 0% (n=242) was associated with better survival than 1%, with little difference between 1% and 39% (n=249). An index of 40% or more (n=9) was associated with the worst survival (chi=14.2, 2 df, P <0.001). After controlling for donor age, the only values of the index related to survival were 40% and above (hazard ratio, 2.96; P =0.01). Donor age group 10 to 39 years old (n=238) had better survival than 1 to 9 years old (n=26) and 40 to 73 years old (n=236) (hazard ratios, 2.83 and 2.06, respectively; P <0.001). An early episode of acute rejection affected survival even at 6 years and later after transplantation (hazard ratio, 1.94; P <0.04).
  
  
  CONCLUSIONS
  Marginal kidneys are identified using the index of chronic damage, but they are so rare that measurement is not necessary on every graft. After routine graft allocation and in the absence of acute rejection, a kidney from virtually any donor in an age group has the same potential as a graft from nearly all others in that group.
authors.affiliation: Department of Pathology, University of Birmingham, Birmingham, United Kingdom. a.j.howie@bham.ac.uk
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Howie
authors.forename: Maria Alice S
authors.initials: MA
authors.lastname: Ferreira
authors.forename: Graham W
authors.initials: GW
authors.lastname: Lipkin
authors.forename: Dwomoa
authors.initials: D
authors.lastname: Adu
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D006084:Graft Rejection; D006085:Graft Survival; D006801:Humans; D007668:Kidney / Q000473:pathology*; D016030:Kidney Transplantation; D008875:Middle Aged; D012189:Retrospective Studies; D014019:Tissue Donors