IMPACT OF GENDER-RELATED DIFFERENCES OF RENAL MASS SUPPLY AND METABOLIC DEMAND ON THE EARLY GRAFT FUNCTION AFTER LIVING DONOR KIDNEY TRANSPLANTATION

Abstract

A40 Aims: It has been reported that graft survival was inferior when the donor was female and the recipient male. Difference of the survival may be explained by an inadequacy of the nephron supply to the functional demand of recipient. An insufficient number of functioning nephrons might fail to meet the metabolic demands of the kidney recipient and lead to hyperfiltration. Theoretically, several hypotheses regarding the gender impact on the early graft function may arise on a base of the nephron mass supply and functional demand. They include whether there are significant differences in renal mass supply of donated kidney by the donor gender, in metabolic demands by recipient gender, and consequently in the early graft functions. To address these questions, we compared the differences in the graft weight prior to implantation between male and female donors as well as in the metabolic demands of recipients such as weight, height, body surface area (BSA), lean body weight (LBW), and body mass index (BMI). Furthermore, we examined the differences in the early graft function in light of the balance between the metabolic demands of recipient and graft nephron supply. Methods: In order to limit other factors that might effect renal allograft function, the study population was restricted to live donor transplants demonstrating immediate function that had neither pretransplant diabetes, ischemic injury, episodes of rejection, nor any complication which might result in a functional decrease of the graft. The weight of donated kidney was measured after flush, and the recipient’s serum creatinine (Scr) was measured on a daily basis postoperatively. When the recipient’s Scr reached the baseline, the recipient’s 24-hour urine was collected for the amount of proteinuria (Upr), creatinine excretion (Ucr), and creatinine clearance (Ccr) calculation. As the parameters of the metabolic demands of donor and recipient, body weight, height, BSA, LBW, and BMI were noted. The variables were analyzed with accordance to donor and recipient gender by independent sample t-test and Chi-square statistics. Results: Male donors were significantly heavier and taller than female donors. Accordingly, the BSA, LBW and BMI of male donors were greater than those of female donors. Prior to the kidney donation, the Ucr, Scr and Ccr of male donors were greater than those of female donors. The true weight of the donated kidney was not statistically different by donor gender. Furthermore, after transplantation, recipient’s Ucr, Ccr, Scr, and Upr were not statistically different by the donor gender. Similarly, male recipients were significantly heavier and taller than female recipients. Post-transplantation, the Ucr and Scr of male recipients were greater than those of female recipients. The true weight of the transplanted kidney was not statistically different by recipient gender. Conclusions: The early graft functions by the gender of recipient and donor are affected by the recipient’s functional demands which are higher in male, rather than by the renal mass supply from donors.