Expanded Criteria Yield Larger Pool of Kidneys for Transplant

‘A good solution in certain situations’

Robert Merion Photo: Lin Jones

More than 64,000 people in the United States today are waiting for a kidney transplant. The need for donated kidneys is growing much faster than the current supply, so some people have to wait for years before a healthy kidney is available. Unfortunately, many can’t afford to wait.

So instead of remaining on kidney dialysis and continuing to wait, more patients are accepting kidneys from expanded criteria donors (ECD). These are older donors and those with pre-existing kidney or medical problems whose kidneys were often not used for transplants in the past.

Even though organs from expanded criteria donors have a higher risk of organ failure, their growing use is adding to the pool of kidneys available for transplantation, and increasing the chances for survival in certain patients with end-stage renal disease.

Robert M. Merion (M.D. 1979, Residency 1986), professor of surgery in the Medical School, directed a nationwide Scientific Registry of Transplant Recipients study to determine which patients would benefit most by taking the ECD kidney now and which patients would be better off waiting for a healthier kidney. Results of the study were published in the December 7, 2005, issue of the Journal of the American Medical Association.

Merion and his colleagues measured the outcomes of patients on dialysis from the day they were placed on the organ wait list. The study looked at all patients in the United States — a total of 109,127 people — who were on dialysis for kidney failure and were added to an organ wait-list between 1995 and 2002, and then followed their progress through July 2004.

In terms of survival, ECD kidneys were shown to have the greatest benefits for patients over the age of 40 and those who would have to wait more than 44 months before a non-ECD kidney was available. Only diabetic patients were found to benefit from ECD kidneys in areas where wait times were shorter. For patients younger than 40, there was no significant advantage to accepting an ECD kidney.

“ECD kidneys are clearly a good solution in certain situations,” says Merion. “This study’s results allow us, with greater clarity than before, to maximize the benefits of ECD kidneys for patients and to match patients with a transplant option that will offer them the best chance for survival.”

—Krista Hopson

For an expanded version of the story:
www.med.umich.edu/opm/newspage/2005/kidneytransplant.htm

For patient information on chronic kidney failure:
www.med.umich.edu/1libr/aha/aha_kdnyfail_sha.htm