Expanded criteria donors for kidney transplantation.

The shortage of deceased donor kidneys for transplantation continues to restrict the full application of this lifesaving procedure to all who might benefit. Increasing reliance on donors with characteristics previously thought to be unsuitable for use in transplantation has led to questions about graft outcomes for recipients of such organs. Careful definition of the expanded criteria donor (ECD) for kidney has facilitated modifications of national organ allocation policy that are designed to increase procurement, improve use, decrease cold ischemia time, and lead to improved outcome. The effects of these policy changes in the United States have been studied recently and are reviewed here. In addition, the impact of ECD kidney transplantation on mortality risk among candidates awaiting deceased donor renal transplantation is examined. Further studies of ECD organs and their recipients are needed to optimize the use of these scarce resources.