P248
Variation of GFR measurements in potential live
kidney donors.
Emma Montgomery1, Caroline Wroe1, Mark Richardson2, Steve Hedley2
1
Renal Department.2 Nuclear Physics Department, James Cook University Hospital, Middlesbrough
BACKGROUND: Evaluation of a potential living kidney donor is a stepwise process to
determine both the suitability and safety for donation. Workup involves a detailed assessment of
renal function, both to ensure sufficient residual function after donation and to provide adequate
graft function in the recipient. The BTS/RA produced guidelines to evaluate renal function and
suggested that GFR should be measured using a reference GFR procedure e.g. 51Cr EDTA1. If
the potential donor has a corrected GFR below a minimum standard then they should not be
considered for donation.1
METHODS: All patients between 1/1/2008 and 1/12/2013 who were assessed as potential live
kidney donors in our area were included in this study. We retrospectively looked at their age,
sex, creatinine, eGFR and normalised GFR (assessed by 51Cr EDTA). The reference mean
values used were created from the British nuclear medicine society GFR guidelines 2 using the
Granerus & Aurell (1981) method. The minimum safety standard for donation was set based on
data from 2949 patients who had donated over a 40-year period 3.
RESULTS: 149 patients were assessed for potential kidney donation. 84(56%) were female and
65(44%) male with a mean age of 49 (range 20-70). 21 potential donors had a nGFR below the
acceptable level and 19 were declined as donors. 2 potential donors asked to be considered even
though their nGFR was below the acceptable level, one has since donated, one is under
consideration. 88.6 % (132) of the subjects all fell below the reference mean and our group was
on average 10% lower than the reference mean GFR.
CONCLUSION: 88.6% of our patients had a nGFR below mean reference values. The
explanation could be that a) within our region subjects have lower a GFR than the rest of the
UK, b) there is a difference in our nuclear physics laboratory performance or c) that the national
reference means created from previous donors are not representative of the overall population.
Our nuclear physics department have reviewed their practice and validated their method,
however no obvious methodological explanation was obtained4. Overall the explanation is
unclear and requires further investigation. Until then, the dilemma remains are we excluding
potential donors unnecessarily or are we appropriately identifying those at higher risk from our
catchment population?
REFERENCES:
1.Andrews PA, Burnapp L, Manas D,et al. Summary of the British Transplantation Society/Renal
Association U.K. Guidelines for living donor kidney transplantation. Transplantation.93(7):666.
2.Fleming JS, Zivanovic MA, Blake GM, Burniston M, Cosgriff PS. Guidelines for the measurement of
glomerular filtration rate using plasma sampling. Nucl Med Commun 2004;25: 759-69
3.Ibrahim HN, et al. Long-term consequences of kidney donation. N Eng J Med 2009; 360: 459-69
4.Peters AM, Howard B, Neilly M, et al. The reliability of glomerular filtration rate measured from
plasma clearance. Eur J Nucl Mol Imaging (2012) 39;715-722.