Optimizing recovery, utilization and transplantation outcomes for kidneys from small, ≤20 kg, pediatric donors.

The optimal balance between maximizing the number versus the outcome of transplantation utilizing kidneys from small (≤20 kg) pediatric donors remains unclear, complicated by the choice of single versus en bloc transplantation with their attendant technical risks. Using the Organ Procurement and Transplantation Network (OPTN) database, we examined kidney recovery and utilization patterns, and 1-year transplant outcomes by single kilogram weight strata. Between January 1, 2005 and June 30, 2010, 2352 kidneys from ≤20 kg donors were transplanted into 1531 recipients, 710 single kidney transplants (SKTs) and 821 en bloc kidney transplants (EBKTs). Increased donor weight was associated with higher rates of recovery, transplantation and SKT. Low donor weight (linear p < 0.001; quadratic p = 0.003), SKT versus EBKT (p = 0.008), increased cold ischemia time (p = 0.003), local versus nonlocal donor (p = 0.0044), low versus high volume center (p = 0.003) and the interaction term between center volume and donor weight (p = 0.0024) were associated with graft failure. Notably, lower donor weight exacerbated the negative impact of low center volume but did not worsen the negative impact of SKT on outcomes. Our data show that EBKT offers superior 1-year survival at the expense of accomplishing one rather than two transplants. However, SKTs yield excellent outcomes when performed at experienced centers.