Does Histopathology of Implanted Kidney According to Banff 07 Help Predict Long-term Transplantation Outcome?

Analyses of peritransplant biopsies of deceased-donor kidneys show high incidence of chronic abnormalities. The question arises whether chronic abnormalities present at implantation determine engrafted kidney fate regardless of other concomitant variables. The aim of this study was to identify risk factors of graft loss considering histopathological changes present at implantation scored according to Banff 07 criteria.

Patients and methods: Inclusion criteria (n = 300) was engraftment between years 2000 and 2008 and availability of implantation biopsy. Analyzed abnormalities present in donor biopsy were arteriolar hyalinization, interstitial fibrosis, intimal sclerotization, tubular atrophy, total inflammation, and percentage of sclerotic glomeruli (Banff classification). Allograft function was estimated by abbreviated Modification of Diet in Renal Disease formula and proteinuria semi-quantitatively by standard dip-stick test. Kaplan-Meier estimate was used to assess graft survival. Searching for independent risk factors of graft survival was performed by means of Cox proportional hazards models (SAS System, SAS Institute Inc, Cary, NC, United States).

Results: In one-factor analyses, predictors of kidney allograft loss were donor age, donor history of diabetes, kidney allograft dysfunction within first posttransplant year, and recipient chronic hepatitis C. In terms of chronic abnormalities, arteriolar hyalinization of any intensity nearly doubled the risk of allograft loss. Independent risk factors of kidney allograft loss in multivariate analysis were donor age, posttransplant diabetes mellitus, proteinuria after engraftment, and recipient hepatitis C.

Conclusion: The effect of arteriolar hyalinization on renal transplant survival is probably interwoven with other predictors of graft loss. Recognizing the negative impact of recipient chronic hepatitis C on graft survival, hepatitis C virus treatment should be provided to patients with advanced chronic kidney disease, patients on wait lists, or patients already transplanted.