Department of Urology, San Raffaele Scientific Institute, Milan, Italy,
Urological Research Institute, San Raffaele Scientific Institute, Milan, Italy,
Kidney Blood Press Res. 2020;45(2):166-179. doi: 10.1159/000504649. Epub 2020 Jan 24.
An accurate assessment of renal function is needed in the majority of clinical settings. Unfortunately, the most used estimated glomerular filtration rate (eGFR) formulas are affected by significant errors in comparison to gold standards methods of measured GFR (mGFR).
The objective of the study is to determine the extent of the error of eGFR formulas compared to the mGFR in different specific clinical settings.
A total retrospectively consecutive cohort of 1,320 patients (pts) enrolled in 2 different European Hospitals (Center 1: 470 pts; Center 2: 850 pts) was collected in order to compare the most common eGFR formulas used by physicians with the most widespread mGFR methods in daily clinical practice (Iohexol Plasma Clearance -Center 1 [mGFR-iox] and Renal Scintigraphy -Center 2 [mGFR-scnt]). The study cohort was composed by urological, oncological, and nephrological pts. The agreement between eGFR and mGFR was evaluated using bias (as median of difference), precision (as interquartile range of difference) accuracy (as P30), and total deviation index.
The most accurate eGFR formula in the comparison with gold standard method (Iohexol plasma clearance) in Center 1 was represented by s-creatinine and cystatin C combined Chronic Kidney Disease-Epidemiology Collaboration-cr-cy, even though the P30 is reduced (84%) under the threshold of 60 mL/min/1.73 m2. Similar results were found in Center 2, with a wider discrepancy between mGFR-scnt and eGFR formulas due to the minor accuracy of the nuclear tool in respect to the mGFR-iox.
The loss of accuracy observed for the formulas at lower values of GFR suggests the mandatory use of gold standards methods as Iohexol Plasma Clearance to assess the correct status of renal function for critical cases. The center 2 showed lower levels of agreement between mGFR and eGFR suggesting that the errors are partially accounted for the Renal Scintigraphy technique too. In particular, we suggest the use of mGFR-iox in oncological urological and nephrological pts with an eGFR lower than 60 mL/min/1.73 m2.
在大多数临床环境中，都需要准确评估肾功能。不幸的是，与金标准的肾小球滤过率（mGFR）测量方法相比，最常用的估计肾小球滤过率（eGFR）公式存在显著误差。
本研究旨在确定不同特定临床环境下，eGFR 公式与 mGFR 相比的误差程度。
本研究回顾性连续纳入了来自 2 家欧洲医院的 1320 例患者（中心 1：470 例；中心 2：850 例），旨在比较医生常用的最常见的 eGFR 公式与日常临床实践中最广泛使用的 mGFR 方法（碘海醇血浆清除率-中心 1 [mGFR-iox]和肾闪烁照相术-中心 2 [mGFR-scnt]）。该研究队列由泌尿科、肿瘤科和肾病科患者组成。使用偏差（差异中位数）、精度（差异四分位距）和准确性（P30）和总偏差指数来评估 eGFR 与 mGFR 的一致性。
在与金标准方法（碘海醇血浆清除率）的比较中，中心 1 最准确的 eGFR 公式是 s-肌酐和胱抑素 C 联合慢性肾脏病-流行病学合作组-cr-cy，尽管 P30 在 60mL/min/1.73m2 以下阈值时降低（84%）。在中心 2 中也发现了类似的结果，由于核工具在 mGFR-iox 方面的准确性较低，因此 mGFR-scnt 和 eGFR 公式之间的差异更大。
对于肾小球滤过率较低值的公式，观察到准确性降低，提示必须使用金标准方法（如碘海醇血浆清除率）来评估肾功能的正确状态，尤其是在危急情况下。中心 2 显示 mGFR 与 eGFR 之间的一致性较低，表明部分误差归因于肾闪烁照相术技术。特别是，我们建议在 eGFR 低于 60mL/min/1.73m2 的肿瘤泌尿科和肾病科患者中使用 mGFR-iox。
