OBJECTIVE: We explore the use of CrCl and combined urea and creatinine clearance as an alternative for GFR assessment.
METHODS: A retrospective study involving 81 kidney donors from 2007 to 2020, with mGFR collected by chromium 51-labeled ethylenediaminetetraacetic acid (51Cr-EDTA) and CrCl and combined urea and creatinine clearance. We analyzed the performance of CrCl and combined urea and creatinine clearance against 51Cr-EDTA. Adequacy of urine volume was taken into consideration.
RESULTS: A total of 81 candidates with a mean age of 44.80 ± 10.77 years were enrolled. Mean mGFR from 51Cr-EDTA was 123.66 ± 26.91 mL/min/1.73 m2, and combined urea and creatinine clearance and CrCl were 122.13 ± 47.07 and 133.40 ± 36.32 mL/min/1.73 m2, respectively. CrCl overestimated 51Cr-EDTA. Though combined urea and creatinine clearance had minimal bias, it had a lower correlation coefficient (0.25 vs 0.43), lower precision (49.51 vs 38.10), and slightly lower accuracy within 30% of 51Cr-EDTA (74.07% vs 76.54%).
CONCLUSIONS: Combined urea and creatinine clearance did not improve the performance of CrCl. Nevertheless, it can potentially be used as first-line GFR assessment, followed by mGFR in selected donors, to ascertain threshold of safe kidney donation. A stringent urine collection method is essential to ensure accurate measurement.
METHODS: This is a retrospective, single-centre study comprising 105 living kidney donor candidates from the year 2007 to 2020. By comparing against 51-Chromium ethylenediamine-tetraacetic acid (51Cr-EDTA), we analysed creatinine clearance for correlation, bias, precision and accuracy.
RESULTS: The study group had a mean age of 45.68 ± 10.97 years with a mean serum creatinine of 64.43 ± 17.68 µmol/L and a urine volume of 2.06 ± 0.83 L. Mean measured GFR from 51Cr-EDTA was 124.37 ± 26.83 ml/min/1.73m2 whereas mean creatinine clearance was 132.35 ± 38.18 ml/min/1.73m2. Creatinine clearance overestimated 51Cr-EDTA significantly with a correlation coefficient of 0.48 (p