The Effect of Donor Kidney Volume on Recipient Outcomes

Abstract

We read with great interest the article by Sikora et al. (1) that outlined the recipient outcomes in relation to the volume of the donor kidney. We recently published a similar study conducted at our institution that documented recipient outcomes 36 months after transplantation. Our analysis revealed that total renal volume and cortical volume adjusted to recipient’s body weight and body surface area correlated with serum creatinine and estimated glomerular filtration rate at 6, 12, and 36 months after transplantation. The odds of the recipient having a serum creatinine greater than 1.5 mg/dL were significantly higher with smaller kidney cortical volume to recipient weight ratio (odds ratio, 4.07; 95% confidence interval, 1.10–15.09) (2). Our study population was also primarily Caucasian, and therefore, this necessitates validation in other populations. However, it corroborates the findings by Sikora et al. (1), and our 3-year follow-up supports their conclusion that “dose” of the kidney is a determinant of recipient graft function. Based on our study, renal volumes are reported routinely at our institution for living kidney donors. We recommend that renal volumes be measured along with renal lengths during the evaluation of the kidney donor. If there is a significant discrepancy between renal volumes and renal lengths, our current practice calls for a split renal function scan to help determine which donor kidney should be harvested. Despite this new data that renal volume can potentially affect recipient renal function, it is imperative to emphasize that the larger kidney or the kidney with the superior function should always remain with the donor. Anitha Vijayan 1 Motoyo Yano2 Vamsi R. Narra2 Kelsey Hoffman3 Thomas K. Pilgram2 Michael F. Lin2 1 Renal Division Washington University in St. Louis St. Louis, MO 2 Mallinckrodt Institute of Radiology Washington University in St. Louis St. Louis, MO 3 Department of Internal Medicine Washington University in St. Louis St. Louis, MO