Wednesday, July 3, 2013

KIDNEY TRIAGE BECOMING MORE SEVERE

Acknowledging reality, the Board of Directors of the United Network for Organ Sharing (UNOS)  accepted recommended changes to the allocation policy for deceased donor kidneys throughout the U.S. at its meeting on June 24-25, 2013. This policy determines how a specific kidney is offered to a specific waiting patient by defining how the UNOS computer generates the specific list in response to availability of a donor.  In the context of the extraordinary discrepancy between people waiting and the number of organs available, several fundamental problems are intended to be improved with the amended policy (see below).

A key change involves implementation of the Kidney Donor Profile Index (KDPI) as a measure of the risk of kidney failure after transplantation, with 100% being the worst and 1% the best possible values. An organ with a KDPI of 20% is more likely to function than 80% of transplanted kidneys - pretty darned good. Since one would not like to transplant an organ that is likely to fail, the KDPI is used as a direct measure of donor kidney quality.

Waiting candidates are stratified into 4 groups based on the KDPI and a second formula, the estimated post-transplant survival (EPTS).  This not-so-subtle means of including the candidate's statistical life expectancy following transplantation is a major step in the allocation scheme, taken in order to maximize the number of life years for the kidney following transplantation (LYFT).  It is based on the candidate age, length of time on dialysis, prior transplantation and presence of diabetes. However, the new policy amendment will incorporate the EPTS to advantage just those 20% of candidates with the best likely survival.

Now, combining the KDPI and EPTS will lead to the 20% of best KDPI organs being matched to pediatric patients and adult patients with the best EPTS. Pediatric patients are still given an advantage for organs with a KDPI up to 35%. Between KDPI of 35-85% adult recipients are addressed by the standard allocation factors already in effect. Above 85% broad sharing (beyond local areas) will be undertaken promptly in order to avoid discarding potentially transplantable organs. 

These changes have been neither reactive nor rapid, but have followed years of debate and formal procedure that included opportunities for input from all stakeholders. Nonetheless, the starkness of  including some healthier candidates while excluding sicker ones from access to the best kidneys, is not lost on anyone involved. This "cherry-picking" of transplant candidates is a deeply distasteful but necessary response to the lack of sufficient resources. Please take a moment to register your opinion about these changes by answering the poll at the bottom right of this webpage - thanks.