title: Validation of the Maryland Aggregate Pathology Index (MAPI), a pre-implantation scoring system that predicts graft outcome.
abstract: Predicting graft outcome after renal transplantation based on donor histological features has remained elusive and is subject to institutional variability. We have shown in a retrospective study that the Maryland Aggregate Pathology Index score reliably predicts graft outcome. We sought to validate the scoring system in our center and a second transplant center. We analyzed 140 deceased donor kidneys pre-implantation biopsies from center 1 and 65 from center 2. The patients had a mean follow-up of 695 ± 424 and 656 ± 305 d respectively. Although MAPI scores were similar, there were significant differences in donor and recipient parameters between both centers. Despite this, MAPI was predictive of graft outcome for both centers by Cox univariate, multivariate and time dependent ROC analysis. For center 1 and 2, three yr graft survival within each MAPI group was statistically equivalent. The three-yr graft survival at center 1 for low, intermediate, and high MAPI groups were 84.3%, 56.5%, and 50.0%, respectively, p ≤ 0.0001, and at center 2 were 83.3%, 33.3%, and 33.3%, p = 0.006. MAPI, which is based on a pre-implantation biopsy, demonstrated similar predictive and outcome results from both centers. As expanded criteria donors (ECD) criteria have redefined marginal kidneys, MAPI has the potential to further define ECD kidneys, increase utilization, and ultimately improve outcomes.
authors.affiliation: Department of Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Philosophe
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Malat
authors.forename: Sunganthi
authors.initials: S
authors.lastname: Soundararajan
authors.forename: Rolf N
authors.initials: RN
authors.lastname: Barth
authors.forename: Wana
authors.initials: W
authors.lastname: Manitpisikul
authors.forename: Nikita S
authors.initials: NS
authors.lastname: Wilson
authors.forename: Karthik
authors.initials: K
authors.lastname: Ranganna
authors.forename: Cinthia B
authors.initials: CB
authors.lastname: Drachenberg
authors.forename: John C
authors.initials: JC
authors.lastname: Papadimitriou
authors.forename: Brian P
authors.initials: BP
authors.lastname: Neuman
authors.forename: Raghava B
authors.initials: RB
authors.lastname: Munivenkatappa
mesh_terms: D005260:Female; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D006084:Graft Rejection / Q000175:diagnosis* / Q000401:mortality; D006085:Graft Survival; D006801:Humans; D007676:Kidney Failure, Chronic / Q000601:surgery*; D007677:Kidney Function Tests; D016030:Kidney Transplantation / Q000379:methods*; D008297:Male; D008396:Maryland; D008875:Middle Aged; D018579:Patient Selection; D019836:Preimplantation Diagnosis / Q000379:methods* / Q000706:statistics & numerical data; D011379:Prognosis; D012307:Risk Factors
keywords: deceased donor kidneys; kidney scoring; marginal donors; suboptimal organs