Donor evaluation is crucial in organ allocation for kidney graft, especially with the growing use of ECDs. Donor kidney function is decisive to predict graft outcome. Nevertheless, serum creatinine (sCr) is still a widespread benchmark, and few data about eGFR equations are available.

Aim was to compare the accuracy of eGFR formulas in estimating donor kidney function and predicting recipient and graft outcome. Secondary endpoint was to assess the predictive role of donor demographic, clinical and renal histological data.

The study enrolled 625 single kidney graft recipients and the corresponding 481 donors (144 kidneys were allocated elsewhere). Mean f-up: 1072.6±702.7 days. Donor GFR was estimated with Cockcroft-Gault (CG), MDRD and CKD-EPI. To counterbalance GFR overestimation in obese donors, CG formula was assessed with actual (ABW) as well as with ideal body weight (IBW). Recipient kidney function was evaluated with MDRD formula at discharge and after 3, 6, 12, 24 months from surgery. BMI, age, gender, history of hypertension or diabetes mellitus, cause of death and histology were recorded. Survival curves were obtained for grafts and recipients.

Recipients: male 61.6%, age 57.5±11.8 ys, BMI 24.1±3.7 kg/m2 (>25=37.3%).

Donors: male 50.1%, age 57.6±15.1 ys, sCr 0.8±0.3 mg/dL, hypertension 51.3%, diabetes mellitus 8.4%, BMI 25.3±3.8 kg/m2 (>25=49.5%). Preimplantation biopsy was performed in 57.6%. Median eGFR (mL/min): CG (ABW)=104, CG (IBW)=87, MDRD=99, CKD-EPI=92.

All eGFR formulas were equally predictive of recipient renal function during f-up (p<0.05), but only CG was significantly correlated with graft survival (p=0.03). Univariate analysis showed, as for 1-year graft function, a negative predictive role of donor hypertension (p=0.00), donor age (p=0.00), female donor gender (p=0.00), cerebrovascular death (p=0.01) and high recipient BMI (p=0.002). No correlation was found between donor histology, donor eGFR and graft outcome. Multivariate analysis confirmed the negative impact of donor hypertension, age and female gender as well as high recipient BMI.

In conclusion, donor eGFR with all formulas predicted graft function. Since CG predicts graft survival, its use with IBW may be more appropriate. Other clinical (donor hypertension, recipients BMI) and demographic (donor age and gender) data should be considered in organ allocation, while the role of histology might be reassessed.

« Back to 2013 American Transplant Congress