Researchers have developed a calculator that estimates the likelihood that a given patient who receives a kidney transplant from a particular living donor would have a functioning kidney five and 10 years after transplantation. The calculator is described in an upcoming issue of the Clinical Journal of the American Society of Nephrology.

To develop the calculator, a team led by John Kalbfleisch, PhD, and Valarie Ashby, MA, from the University of Michigan, analyzed data on 232,705 recipients of kidney transplants from 1998 to 2012 who were listed in the Scientific Registry of Transplant Recipients. After taking into consideration donor and recipient characteristics, the investigators found that certain mismatches with respect to gender, weight, body size, genetic make-up, and age were associated with increased risks of graft failure. The findings were used to create a calculator of estimated graft survival following transplantation of kidneys from living donors.

Kalbfleisch noted that an area where this calculator may be especially useful is in kidney paired donation (KPD). Many kidney transplant candidates have willing living donors, but there are often incompatibilities with respect to blood type or genetic makeup between the two.

In KPD programs, pools of incompatible donor and recipient pairs are formed with the aim of arranging exchanges to help overcome these incompatibilities. In some instances, a candidate with a compatible donor may decide to join a KPD pool with the purpose of seeking a better match through an exchange. When compatible pairs join a pool, this can be beneficial to other pairs in the pool as well.

“Our calculator allows the candidate with a compatible donor to compare the estimated graft survival for a kidney from their donor, versus one from another donor in the KPD pool,” said Kalbfleisch.

Study co-authors include Alan Leichtman, MD, Michael Rees, MD, Peter Song, PhD, Mathieu Bray, MS, and Wen Wang, MS.

Rees reports receiving grant support for the Alliance for Paired Donation from Novartis and Sanofi Pharmaceuticals and Optum. The authors reported no other financial disclosures.