Impact of Graft Kidney Volume and Weight on Graft Function in Living Donor Kidney Transplantation

Abstract

Background: Low functional nephron mass and graft kidney-recipient body size mismatch can lead to poor graft function. To examine the impact of the ratios of the surrogates to recipient body surface area (BSA) and body weight on graft function within 5 years post-transplantation, we measured the graft kidney volume, using computed tomography with 3-dimensional reconstruction before transplantation, and measured the graft kidney weight during surgery in living donor kidney transplantation (LDKT). Methods: Between February 2004 and November 2013, 142 LDKT recipients without delayed graft function, acute rejection, or infection within 5 years of transplantation were included. The graft function and its relations with graft kidney volume and its weight were analyzed. Results: The graft kidney volume/recipient BSA ratio showed correlation with the estimated glomerular filtration rate (eGFR) of recipients after 3 years post-transplantation. We found a difference in the graft function between recipients with a graft kidney volume/recipient BSA ratio of ≥80.4 mL/m and those with a ratio of <80.4 mL/m (P<0.05). Multivariate analysis showed that the graft kidney volume/recipient BSA ratio, the graft kidney weight/recipient body weight ratio, donor age, donor eGFR, and donor/recipient BSA ratio are independent predictors of graft function at each period of transplantation (P<0.05). Conclusions: The graft kidney volume of living donors may predict graft function and during living donor and recipient matching, both the potential volume of the donated kidney and the body size of the recipient should be considered.