Performance scores and kidney discard rates: the challenging balance for transplant centers

This month in BMC Nephrology, a study by Lee et al. found that the survival rates of dual kidney transplant grafts, from deceased donors over the age of 70, were similar to those of single kidney transplant grafts. This study questioned whether this practice could in the future expand the donor pool. In our third BMC Nephrology blog, Blog Editor Dr. Sumeska Thavarajah explores the challenges that transplant centers face in sourcing sufficient, acceptable kidney allografts and how this new research could inform future strategies to overcome current barriers.

With the rising rates of obesity, type II diabetes and an aging population, the number of individuals developing end-stage renal disease (ESRD) is increasing globally.  With more individuals seeking kidney transplantation, the gap between those waiting for a transplant, and available kidney allografts, is unfortunately widening. Efforts with more potent immunosuppressive agents, protocols with desensitization, educational efforts, altruistic donors, and swap programs have made live donor transplants more accessible.

However, the expansion of live donor programs alone cannot accommodate all those on transplant waiting lists so nephrology care providers are looking more closely at the practices of using deceased donor allografts. Many of these allografts are discarded following biopsy, due to disease or damage during organ procurement. Discard rates of up to 20% have been reported in the US.  The difference in discard rates in other countries such as the 9% rate in France raise the question about possible differences in criteria for discards.

Are we discarding too many kidneys?

This week in BMC Nephrology, Lee et al. reported on a South Korean hospital’s experience of utilizing allografts from deceased donors over the age of 70, with creatinine levels of >3.0mg/dl or GFR of less than 30mL/min. In these cases, both kidneys were transplanted into recipients that tended to be older and more likely to have co-morbidities, such as hypertension and diabetes.  Though a small study of 15 cases of dual kidney transplants, versus 124 recipients of standard criteria donor (SCD) and 80 recipients of the expanded criteria donor (ECD), the positive results at least warrant the examination of current practices which can lead to discarding allografts. The groups had similar patient survival rates, nadir creatinine and time to nadir creatinine. This single center’s experience prompts the question – are we discarding too many kidneys that could provide older recipients with comorbidities possibly improving their survival compared to remaining on dialysis and a better quality of life?

Chess pieces
Image Source: Pixabay

Recognition of the number of hepatitis C positive allografts that were being discarded due to the lack of Hepatitis C positive recipients led to work on protocols allowing for transplantation into hepatitis C negative recipients while using new antiviral therapies. Beyond the development of new protocols, we need to look at current policies and regulations that may impact on the decisions by transplant centers to use certain organ offers.

Doctor, stethoscope
Image Source: Pixabay

In the US, regulations by Centers for Medicare Services (CMS) help to protect patients by reporting patient and graft survival rates and how this could influence transplant centers to be less conservative about using those allografts from donors that are older and have more comorbidities. In a 2016 analysis of low-performance score transplant centers, Schold et al. noted in subsequent years the outcomes would improve but this was accompanied by greater rate of patient removal from waiting lists (28.6 more removals /1000 year follow up, p < 0.001) and from a drop in transplant rates (-11.9/1000 years follow up, p < 0.001). While it is important to look at all allograft offers with a goal of a successful transplant, are we too quick or too conservative in our use of less than perfect kidneys?

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