Kidney transplantation is the preferred treatment for end stage renal disease (ESRD), yet demand for kidneys far exceeds supply. One strategy to increase the donor pool is to use kidneys from small, pediatric donors. However, programs may be reluctant to transplant single kidneys from small pediatric donors due to technical challenges, which may result in inferior outcomes.

To mitigate the complications associated with transplanting kidneys from small pediatric donors singly, both kidneys, including the vena cava and aorta, can be transplanted en bloc into a single recipient. However, there are currently several challenges to allocating en bloc kidneys:

• There is currently no OPTN policy regarding allocation of en bloc kidneys
• The Kidney Donor Profile Index (KDPI) programmed into DonorNet® doesn’t consider how kidneys will be used (en bloc or single) or acknowledge the improved function of en bloc kidneys, which could screen medically suitable candidates off the match run. In addition, there are other programming limitations that make en bloc kidney allocation a challenge

The proposed policy resolves these problems by providing explicit direction to organ procurement organizations (OPOs) on when to allocate en bloc kidneys. The policy includes donor criteria regarding the type of kidneys that can be allocated en bloc and mandates that programs must indicate in WaitListSM that they accept en bloc kidneys, thus expediting placement of en bloc kidneys to programs that will transplant them. In addition, the Kidney Transplantation Committee (Committee) proposes masking the KDPI score for en bloc kidney offers to prevent potentially eligible candidates from being screened off the match run for kidneys from high KDPI donors.

This proposal aligns with three OPTN strategic goals. First, it should increase the number of transplants by utilizing kidneys previously left unrecovered or discarded. Second, it should improve outcomes for waitlisted kidney candidates and transplant recipients as studies indicate when kidneys from a small pediatric donor are transplanted into a recipient en bloc versus singly, they confer comparable to superior outcomes. In addition, accepting kidneys en bloc may shorten a candidate’s time on the waitlist, conferring not only a survival advantage, but also several other additional benefits. Finally, this proposal should increase efficiency in management of the OPTN as OPOs should no longer have to contact the Organ Center for guidance or assistance in allocating en bloc kidneys.

The proposal has been amended after its first round of public comment. Following the spring 2017 cycle, the Committee voted to remove the provision granting OPOs the option to allocate kidneys from donors weighing between 15 and 25 kg en bloc or as singles and added a provision mandating en bloc allocation for en bloc kidneys from donors weighing 20kg or less. Following the June 2017 Board of Directors meeting, the Committee lowered the mandatory en bloc allocation donor weight threshold to 18kg in response to feedback.