Influence of Preoperative Allograft Function (Effective Renal Plasma Flow) on the Short-Term Outcome Following Living Donor Kidney Transplantation

Objectives: Predonation kidney function is supposed to be an important factor affecting graft outcome. Controversial evidence suggests that higher predonation glomerular filtration rate (GFR) positively correlated with posttransplant graft outcome. The purpose of this study was to examine the relationship between living donor graft kidney function as measured by effective renal plasma flow (ERPF) and short-term graft function. Methods: We performed a retrospective analysis of 45 patients who underwent living donor renal transplantation at our institution from 2001 to 2007. The comprehensive nuclear medicine evaluation of donors' ERPF was performed before laparoscopic nephrectomy. The preoperative absolute ERPF-recipient body surface area (F/BSA) ratio and absolute ERPF-recipient body weight (F/Wt) ratio were determined for each donor-recipient pair. Posttransplant graft function was estimated by the four-variable Modification of Diet in Renal Disease (Chinese MDRD) equation. Results: Estimated GFR correlated with F/BSA ratio at 3 months and 6 months (Pearson r = .495, P = .001 and r = .441, P = .012). Estimated GFR correlated with F/Wt ratio at 3 months and 6 months (r = .567, P < .001 and r = .453, P = .009). The correlations between the estimated GFR at 3 months and other variables were investigated. However, in the final multivariate model, F/BSA ratio and F/Wt ratio were the independent predictors of graft function. Conclusion: Preoperative ERPF can be used to calculate F/BSA and F/Wt ratios before living donor kidney transplantation. Our study provided evidence that F/BSA and F/Wt ratios may be considered predictive indices for short-term outcomes. An extreme discrepancy should be avoided between preoperative allograft function (absolute ERPF) and recipient body surface area or body weight.