Combined Dual-Kidney Liver Transplantation in the United States: A Review of United Network for Organ Sharing/Organ Procurement and Transplantation Network Data Between 2002 and 2012.

In kidney-alone recipients, dual-kidney transplantation using "higher-risk" donor organs has shown outcomes comparable to those of single-kidney transplantation using extended criteria donor (ECD) organs. To investigate the feasibility of a similar approach with combined kidney-liver transplantation, we identified 22 dual-kidney liver transplantations (DKLTs) and 3044 single-kidney liver transplantations (SKLTs) performed in the United States between 2002 and 2012 using United Network for Organ Sharing/Organ Procurement and Transplantation Network registry data. We compared donor/recipient characteristics as well as graft/recipient survival between DKLT recipients and SKLT recipients of "higher-risk" kidneys (ECD and high kidney donor profile index [KDPI; >85%] donors). Despite having overall similar donor and recipient characteristics compared with both "higher-risk" donor groups, recipient survival in the DKLT group at 36 months was markedly inferior at 40.9% (compared with 67.5% for ECD SKLT recipients and 64.5% for high-KDPI SKLT recipients); nondeath-censored graft survival did not differ. Death was the most common cause of graft loss in all groups. Contrary to dual-kidney transplantation data in kidney-alone recipients, DKLT recipients in our study had inferior survival when compared with SKLT recipients of "higher-risk" donor kidneys. These findings would suggest that dual kidney-liver transplantation has an uncertain role as a strategy to expand the existing kidney donor pool in combined transplantation.