Computer Models Successfully Link Donors and Kidney Transplant Patients

New computer models can link strangers in a life-saving chain of kidney transplants, promising to increase the overall number of transplants and overcome obstacles posed by logistics or donors who renege, reveals a new study.

Researchers at Boston College (MA, USA) designed the donor registry software programs to optimize economic "matching market" principles involved in kidney transplantation by sifting through thousands of pairs of recipients and their living donors, analyzing participant characteristics, and then constructing an optimal chain of transplant pairs based on similar scores, imposing an order on these exchanges by overcoming issues that disrupt a market. By generating a donation chain, the software allows for greater flexibility, since not all surgeries must take place at the same time in the same hospital as in paired kidney donation surgeries, which are performed simultaneously to reduce the possibility of a donor backing out once a friend or relative has received a kidney.

The researchers highlighted a chain of kidney transplantations that started with a 28-year-old man in July of 2007 and led to 10 transplantations coordinated during 8 months by two large paired-donation registries, the U.S. 25-state Alliance for Paired Donation and the Incompatible Kidney Transplantation Program at Johns Hopkins Hospital (Baltimore, MD, USA). The transplantations took place at six medical centers in five U.S. states. In the case of five of the transplantations, the donors and their coregistered recipients underwent surgery simultaneously. In the other five cases, "bridge donors" continued the chain as many as 5 months after the coregistered recipients in their own pairs had received transplants. Three kidneys from living donors were shipped, two of them using commercial flights, rather than requiring donors to travel to the recipient's hospital. The study describing the new donations chain and the specific case was published in the March 12, 2009, of the New England Journal of Medicine (NEJM).

"The 'Good Samaritan' who comes forward to donate a kidney serves as the catalyst for a series of donations in a much more efficient system," said lead author associate professor Utku Unver, Ph.D., a theoretical economist. "It is not an easy decision to give up a kidney to help a stranger. These advances may encourage more donors because they now know they can save many lives."

The researchers conclude further that kidney donor chains could shorten wait times on lists of unmatched patients in line for deceased-donor organs, since the data-driven approach to transplantation pairings should shrink the rolls of patients on waiting lists. The scope of the databases can pair these patients with suitable living donors, who account for approximately one-third of the 14,000 kidney transplantations that take place annually in the United States.

Related Links:
Boston College