Background: The number of patients with end-stage renal disease is growing, while the number of transplanted organs remains quite stable. Using expanded criteria donor's (ECD) organs is one of the strategies for making more transplants available. Histological findings of biopsies obtained prior to transplantation may play a significant role in kidney evaluation. Aim: The aim of this study was to investigate the influence of histopathological lesions on transplant kidney graft's function and survival.
Material/Methods: One hundred and seventy two patients received cadaveric renal transplants between January 1st, 2006 and August 31st, 2008. Data on recipients was collected. In one hundred forty seven cases, renal biopsy specimens obtained perioperatively were available. Chronic histological changes were evaluated. Patient's and graft's survival, as well as immediate, delayed and slow graft function were analysed. Kidney function was assessed by serum creatinine concentration and creatinine clearance according to Cockroft-Gault formula at seven days, 1, 3, 6, 12 and 24 months post transplantation.  All patients were followed-up for three to thirty five months.
Results: Average 1-year graft's survival was 86.9% for the whole group and mean creatinine concentration was 1.58 mg/dl. One case of primary nonfunction was observed (0.6%). More than 25% of transplanted kidneys were harvested from ECD. A correlation was observed between chronic histological changes "inherited" from the donor and graft's survival/function. Cortical interstitial fibrosis, cortical tubular atrophy, arteriosclerosis, arteriolar hyalinization and glomerulosclerosis found in biopsies were associated with higher creatinine concentration and lower creatinine clearance. Additionally cortical interstitial fibrosis, arteriosclerosis and glomerulosclerosis were associated with higher incidence of graft's loss.
Conclusions: There is a correlation between chronic histological lesions and
kidney graft function and survival.

Keywords: Kidney Transplantation