How do I get a kidney from a deceased donor?

The new kidney allocation system was implemented in December 2014 after more than a decade of careful consideration. It was designed to maximize the years of life gained through transplantation and to reduce the discard rate for marginal kidneys. There is more sharing of kidneys outside of the local area due to regional and national priority for very highly sensitized patients, as well as the use of a combined local/regional list for more marginal kidneys. However, substantial geographic disparities continue to exist as this was not the primary goal of the new system.

The new system does use dialysis start time to calculate waiting time but early referral and listing are still very important. Patients that never go on dialysis and those with shorter duration on dialysis prior to transplant have better outcomes. I am fortunate to work in the Midwest where the waiting time for organs is very short. Iowa is a flyover state but because of the very long waiting times for organs on the east and west coasts, Iowa has become a fly to state for kidney transplants. As patients have become more aware of the allocation system, they are willing to travel to transplant program outside of their region to improve their chances of being transplanted.

The origin of the patients served by the Iowa Methodist Transplant Center. 

The current kidney allocation system has several major components:

• Pre-registration dialysis time is used to calculate the candidate’s waiting time.
• If not on dialysis at time of registration, waiting time will begin to accrue once they have a glomerular filtration rate (GFR) <20 ml/min.
• Kidney Donor Profile Index (KDPI) is used to measure the quality of the kidney. 
• Expected Post Transplant Survival (EPTS) score is calculated for adult recipients  based on four factors: age, time on dialysis, current diabetes, and previous transplant.
• The donor KDPI and the recipient EPTS score are used for longevity matching. 
• KDPI <20% kidneys are first offered to adult candidates with EPTS scores < 20%. If a match is not found then they are offered to candidates with EPTS score>20% 
• Pediatric recipients (age<18yrs) receive priority for kidneys with KDPI <35%
• Sensitized patients receive priority points on a sliding scale. The very highly sensitized candidates with CPRA of 98%, 99%, and 100% also receive local, regional, and national priority, respectively.
• Blood type B candidate can accept a kidney from an A2  or A2B  donor. This requires informed consent and monitoring of titers every 90 days to remain eligible. 
• Kidneys with KDPI>85% are placed on a separate list to increase utilization. This requires informed consent. 
• If a patient has donated a kidney, liver segment, lung segment, partial pancreas, or small bowel within the U.S. or its territories, he or she is qualified to receive priority.

What is KDPI? 

The kidney donor profile index (KDPI) combines 10 donor factors into a single number that summarizes the potential risk of graft failure after kidney transplant. 

1.  Age
2. Height 
3. Weight 
4. Ethnicity
5. History of Hypertension 
6. History of Diabetes 
7. Cause of Death
8. Serum Creatinine 
9. Hepatitis C Virus (HCV) Status 
10. Donation after Circulatory Death (DCD) Status

It is not intended to serve as the only metric for determining donor suitability. Indeed the C-statistic for this is 0.6, so a little better than a coin toss. Many of the factors have no bearing on long-term function.  Pediatric en-bloc kidneys and dual kidneys will have very high KDPI even though they will work far better than a single adult kidney with KDPI<85.

The dual usage of kidneys has been shown to confer a survival advantage compared to single kidney transplantation. Kidneys from donors that meet at least two of the following donor criteria are eligible to be allocated to the same patient:

• age>60

• eCrCl<65 ml/min based on admission creatinine (Cr)

• rising Cr (>2.5mg/dl)

• long-standing hypertension or diabetes

• 15%<glomerulosclerosis<50%

The transplant rate at The Iowa Methodist Transplant Center is several times higher than the region and it has one of  the shortest waiting times for kidney transplantation in the country. I am often asked by Iowans and non-Iowans why this is.  For me the biggest barrier to transplantation is the cold ischemia time. That is the time from clamping of the vessels in the donor to restoring the blood flow to the organ in the recipient. For kidneys, I aim to keep this less than 24 hours as each hour of cold ischemia time is associated with a 5% increased odds of delayed graft function.

The outcome depends on many donor, graft and recipient factors; there is no substitute for experience. I consider the donor's comorbidities, the biopsy of the kidney and its performance on the pulsatile perfusion machine to determine usability. This approach allows me to consider kidneys other surgeons/centers may decline. Our patients have benefited tremendously from this and renal failure patients from around the country are flocking to Iowa to list with the Iowa Methodist Transplant Center.

A very helpful resource for patients looking to list with centers with shorter waiting times is www.txmultilisting.com

Patients should also visit the SRTR website to compare center outcomes and the OPTN webiste to assess transplant center volumes/activity.

SRTR
OPTN center data