Abstract: SA-OR079

Estimated GFR before Living Kidney Donation as a Predictor of Postdonation Measured GFR

Session Information

Category: Transplantation

  • 1702 Transplantation: Clinical and Translational

Authors

  • van Londen, Marco, University Medical Center Groningen, Groningen, Netherlands
  • Weijden, Jessica Van der, University Medical Center Groningen, Groningen, Netherlands
  • Pol, Robert, University Medical Center Groningen, Groningen, Netherlands
  • Sanders, Jan-Stephan, University Medical Center Groningen, Groningen, Netherlands
  • Berger, Stefan P., University Medical Center Groningen, Groningen, Netherlands
  • Bakker, Stephan J.L., University Medical Center Groningen, Groningen, Netherlands
  • Navis, Gerjan, University Medical Center Groningen, Groningen, Netherlands
  • De Borst, Martin H., University Medical Center Groningen, Groningen, Netherlands
Background

In living kidney donor screening, precise renal function measurement is vital to ensure adequate postdonation renal function. Measured GFR (mGFR) is the gold standard, but costly and laborious. We tested the capacity of predonation estimated GFR (eGFR) equations to predict postdonation mGFR.

Methods

In a single-center prospective cohort study in 750 living kidney donors, we determined predonation mGFR (continuous iothalamate) including dopamine stimulation, and creatinine-based eGFR (CKD-EPI, Cockcroft-Gault and MDRD equations), as well as mGFR at 3 months postdonation. We used linear regression, Receiver Operating Characteristic curves, and Bayesian statistics to test the performance of eGFR equations.

Results

Mean donor age was 51±11 years, 48% of donors were male. Predonation mGFR was 102±16 ml/min/1.73 m2, stimulated mGFR was 110±18 ml/min/1.73 m2, eGFRCKD-EPI was 88±14 ml/min/1.73 m2, eGFRCG was 93±19 ml/min/1.73 m2, and eGFRMDRD was 86±16 ml/min/1.73 m2. Postdonation mGFR was 65±11 ml/min/1.73 m2. Predonation mGFR and the results of the three eGFR formulas were positively associated with postdonation mGFR (mGFR R2=0.49, dopamine stimulated mGFR R2=0.34, eGFRCKD-EPI R2=0.21, eGFRCG R2=0.22, eGFRMDRD R2=0.14). A predonation eGFRCKD-EPI >102 ml/min/1.73 m2 (present in 16% of donors) excludes a postdonation mGFR <60 ml/min/1.73 m2 with a specificity of 100% (AUC 0.74), for predonation eGFRCG this threshold is 114 ml/min/1.73 m2 (AUC 0.78) and for eGFRMDRD 114 ml/min/1.73 m2 (AUC 0.70). A predonation eGFRCKD-EPI of 95 ml/min/1.73 m2 (present in 30% of donors) excludes a postdonation mGFR of <50 ml/min/1.73 m2 with 100% specificity (AUC 0.78), for predonation eGFRCG this threshold is 105 ml/min/1.73 m2 (AUC 0.82) and for eGFRMDRD 97 ml/min/1.73 m2 (AUC 0.74).

Conclusion

We provide cut-off values for predonation donor eGFR to select donors with a high probability of good renal function postdonation without requiring mGFR measurement. In order to avoid incorrect exclusion of a large proportion of donors, additional renal function tests such as measured GFR are warranted in donors with an eGFRCKD-EPI <95 ml/min/1.73 m2.

Funding

  • Government Support - Non-U.S.