Kidney Allocation System (KAS)

On Dec. 4, 2014, the United Network for Organ Sharing (UNOS) and the Organ Procurement and Transplantation Network (OPTN) enacted a new approach to allocating kidneys to those on the transplant waiting list.

The previous kidney matching system helped tens of thousands of people successfully receive kidney transplants, but there were things that could be improved. Issues included some kidney recipients were not receiving kidneys that work as long as they needed them to, thus requiring re-transplantation at some point later in life. Another issue was that patients with difficult-to-match blood type or highly sensitive immune response were waiting significantly longer than other patients.

The new Kidney Allocation System (KAS) is the result of years of review and consensus-building among transplant professionals, patients and others personally connected to kidney donation and transplantation. They set out with one primary goal in mind: make the system better without making major changes to the parts of the system that worked well.

KAS and the PKD community

UNOS’s new KAS aims to help more people have longer function with their transplanted kidney by matching the donated kidney that has the longest potential life with the recipient who has the longest potential life. Additionally, the KAS will give priority to groups of people who are hard to match based on blood type or immune sensitivity.

This system is will be beneficial to younger patients with ARPKD but may negatively impact patients who need transplants later in life, including ADPKD patients. Age is only one factor, however, and an individual in their 50’s or 60’s who are not diabetic and not on dialysis could be among the top candidates. This is why we encourage you to speak with your medical team to be referred to the transplant list early and, ideally, before starting dialysis.


The PKD Foundation does not offer medical advice. The information shared on this website is not intended to be a substitute for professional medical advice, diagnosis, or treatment. We strongly recommend that your care and treatment decisions be made in consultation with your healthcare professional team.