Division of Nephrology, University of Wisconsin School of Medicine and Public Health, Madison, WI.
Department of Nephrology and Hypertension, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH.
Transplantation. 2020 Mar;104(3):575-582. doi: 10.1097/TP.0000000000002797.
Glomerular filtration rate (GFR) assessment is a key aspect in the evaluation of living kidney donor candidates; however, data on performance of commonly used methods are limited.
We examined 769 living kidney donor candidates with 24-hour urine collections assessed as accurate by comparing measured creatinine excretion rate (CER) to CER estimated using a 4-variable equation previously developed and validated using robust methodology.
Of all collections, 42.6% would have been deemed inaccurate, mostly under-collections, using the conventional weight- and gender-based CER estimation. Creatinine clearance (CrCl) overestimated I-iothalamate GFR (iGFR), estimated GFR (eGFR), underestimated iGFR, and their average [Avg (CrCl and eGFR)] essentially eliminated the GFR bias (median bias = +2.2, -5.4, and -1.0 mL/min/1.73 m, respectively; P < 0.001). This held true for all subgroups except blacks, where all 3 measures overestimated iGFR. Avg (CrCl and eGFR) also offered modestly improved accuracy compared with CrCl alone, as measured by the proportion of values falling within 10% (50.7% versus 45.3%; P = 0.009) and 30% of iGFR (94.5% versus 89.3%; P < 0.001).
When measured GFR is unavailable, the Avg (CrCl and eGFR) provides a better estimate of kidney function in kidney donor candidates than either measure alone, although in blacks the estimates are neither better nor worse.
肾小球滤过率（GFR）评估是评估活体肾供体候选人的关键方面；然而，常用方法的性能数据有限。
我们检查了 769 名活体肾供体候选人，他们的 24 小时尿液收集通过比较测量的肌酐排泄率（CER）与使用先前使用稳健方法学开发和验证的 4 变量方程估计的 CER 来评估为准确。
所有收集物中，使用传统的基于体重和性别的 CER 估计，42.6% 的收集物将被认为不准确，主要是收集不足。肌酐清除率（CrCl）高估了碘海醇 GFR（iGFR）、估计的 GFR（eGFR），低估了 iGFR，并且它们的平均值 [平均（CrCl 和 eGFR）] 基本上消除了 GFR 偏差（中位数偏差分别为+2.2、-5.4 和-1.0 mL/min/1.73 m；P <0.001）。这在除黑人以外的所有亚组中均成立，其中所有 3 种测量方法均高估了 iGFR。平均（CrCl 和 eGFR）也与单独的 CrCl 相比，提供了略高的准确性，以值落在 iGFR 的 10%（50.7% 对 45.3%；P = 0.009）和 30%（94.5% 对 89.3%；P <0.001）内的比例来衡量。
当无法测量 GFR 时，平均（CrCl 和 eGFR）提供了比单独测量更好的肾供体候选者的肾功能估计，尽管在黑人中，这些估计既不差也不好。
