To the Editor:
We read with interest the article by Vacher-Coponat et al  demonstrating inferior early posttransplant outcomes for recipients of right versus left deceased donor kidneys in a large registry from Australia and New Zealand. Aside from an increased risk of early failure, the analysis reveals that right kidneys are associated with a greater incidence of delayed graft function and slower decline in serum creatinine. Several small series have previously examined whether right-sided kidneys have a higher risk of graft loss [2, 3]. The current report by Vacher-Coponat et al  offers ongoing support for a technical etiology.
Although donor renal laterality is generally not one of great importance in the allocation decision for deceased donor kidneys, the decision is important for live donor transplantation. In general, the left kidney is selected due to the longer renal vein, particularly in the setting of laparoscopic donor nephrectomy where the renal vein length may be compromised by the method used to secure the vein. We previously tested the hypothesis that right-sided living donor kidneys would have an increased risk of graft loss compared to the left side among a cohort of over 35 000 live donor kidney transplants from the United States . Right-sided nephrectomy increased the risk of allograft loss within 90 days of transplant compared to the left (OR = 1.49, p < 0.01). Stratification by procedure type demonstrated that both right laparoscopic (OR 1.58, p < 0.01) and right open donor nephrectomy (OR = 1.38, p = 0.02) were associated with an increased risk of graft failure compared to the left side. Right-sided kidneys, whether procured via laparoscopic or open techniques, had an increased incidence of delayed graft function, indicating that issues related to laparoscopic donation were unlikely contributors to right-sided allograft loss. Additional potential technical explanations for these findings were not discernable from the data.
These articles by Vacher-Coponat et al and Hsu et al support a greater risk of allograft loss among both deceased and living right-sided kidneys [1, 4]. While the overall magnitude of the hazard is modest, it may be of some importance when selecting the laterality of either a deceased or living donor allograft, may warrant consideration in the statistical evaluation of renal transplant cohorts, and offers opportunities for clinical innovation to reduce risk associated with the right kidney.
J. W. Hsu1, P. P. Reese2,3, A. Naji4, M. H. Levine4, and P. L. Abt4,*
1St. Francis Medical Center, Department of Transplantation, Peoria, IL
2Department of Biostatistics and Epidemiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA
3Renal Division, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA
4Division of Solid Organ Transplant, Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA
*Corresponding author: Peter L. Abt, firstname.lastname@example.org