Introduction: The use of kidneys from expanded criteria donors (ECD) is increasing due to donor shortage. Predicting the outcome of these grafts is still a challenge. The aim of this study is to determine which factors are related to primary non-function (PNF), delayed graft function (DGF) and overall graft survival for kidneys retrieved from expanded criteria donors (ECD).
Methods: From January 2017 to December 2019 we retrospectively evaluated the pre-transplantation renal biopsy results and the pulsatile machine renal vascular resistance (RVR) of 97 kidneys from ECD that were implanted in our hospital. Those kidneys came from 40 donors after brain death and 57 from donors after cardiac death (6 Maastricht II, 50 Maastricht III and 1 Maastricht IV).
The recipients’ evolution was analyzed. The association of the studied factors with PNF and DGF of the graft were studied with a logistic univariate regression. A Kaplan-Meier model was used to study its relationship with overall graft survival.
Results: The renal biopsy score was the only analyzed variable that presented with a statistically significant relation with PNF (OR 1.86, p<0.05), specifically the % of glomerulosclerosis (OR 1.11, p<0.05) and the grade of interstitial fibrosis (OR 5.36, p<0.05).
Regarding DGF, the age of the donor (OR 0.90, p<0.05), serum creatinine >1.5 mg/dl (OR 11.57, p<0.05) and donation after cardiac death (OR 3.1 p<0.05) showed statistical difference. The recipient’s age and having diabetes were also related to developing DGF (OR 0.95, p<0.05 and OR 2.83, p<0.05). None of the biopsy results or the perfusion machine parameters resulted in statistically significant differences.
Overall graft survival was inferior for grafts with RVR = 0.5 and/or renal biopsy score = 4 (p < 0.05) (Figure 1). Presenting with DGF was not related to a worse graft survival (p=0.114).
Conclusions: In this unicenter study, factors associated with PNF were related to graft biopsy results, whereas DGF was influenced by clinical donor and recipient characteristics. Overall survival of the graft is inferior for those grafts with RVR = 0.5 or renal biopsy score = 4.
Source of Funding: There is no source of funding to disclose.