Peters A Michael, Bird Nicholas J, Halsall Ian, Peters Christina, Michell A Robert
Department of Nuclear Medicine, Addenbrooke's Hospital, Cambridge, UK.
Ann Clin Biochem. 2009 Jan;46(Pt 1):58-64. doi: 10.1258/acb.2008.008078.
Estimation of glomerular filtration rate (GFR) using plasma creatinine remains controversial, especially when GFR approaches normal values. The aim was to re-examine estimated GFR (eGFR) using dual-reference GFR measurements.
eGFR (simplified modified Modification of Diet in Renal Disease equation) was compared with GFR measured with iohexol for predicting GFR measured with (51)Cr-ethylenediaminetetraacetic acid (EDTA). Dual six-sample GFR (20-240 min postinjection) was measured in 60 patients and 20 normal volunteers with (51)Cr-EDTA (GFR(EDTA)) and iohexol (GFR(iohexol)) injected into separate arms and sampled contralaterally. This was repeated in the normal volunteers under fasting conditions (twice in nine). Percentage bias, imprecision (SD of bias) and disagreement (sign-less difference) between eGFR and GFR(EDTA) were compared with those between GFR(iohexol) and GFR(EDTA).
Changes between fasting and postprandial eGFR correlated significantly with corresponding changes in GFR(iohexol) and GFR(EDTA). eGFR predicted GFR(EDTA) less precisely (SD 19.9%) than GFR(iohexol) (10.5%; P < 0.01). Although eGFR showed a poorer correlation with GFR(EDTA) when GFR(EDTA) > 80 mL/min/1.73 m(2) compared with <80 mL/min/1.73 m(2), there was no significant difference with respect to imprecision or disagreement of >20 or 30%. However, eGFR was closer than GFR(iohexol) to GFR(EDTA) in a higher fraction of studies when GFR(EDTA) > 80 mL/min/1.73 m(2) (28/60) than when it was <80 mL/min/1.73 m(2) (9/37; P < 0.05).
eGFR is inferior to GFR(iohexol) for predicting GFR(EDTA). The disagreement between GFR(iohexol) and GFR(EDTA) illustrates the extent to which uncertainty in GFR(EDTA) contributes to the performance of eGFR. eGFR performs no better at lower, compared with higher levels of GFR.
使用血肌酐估算肾小球滤过率（GFR）仍存在争议，尤其是当GFR接近正常范围时。本研究旨在通过双参考GFR测量值重新评估估算GFR（eGFR）。
将eGFR（简化的改良肾脏病饮食公式）与用碘海醇测量的GFR进行比较，以预测用（51）铬 - 乙二胺四乙酸（EDTA）测量的GFR。对60例患者和20名正常志愿者进行双六样本GFR测量（注射后20 - 240分钟），将（51）铬 - EDTA（GFR（EDTA））和碘海醇（GFR（碘海醇））分别注入两侧手臂，并从对侧取样。在正常志愿者空腹状态下重复上述操作（9例中有2例）。比较eGFR与GFR（EDTA）之间的百分比偏差、不精密度（偏差的标准差）和不一致性（无符号差异）以及GFR（碘海醇）与GFR（EDTA）之间的相应指标。
空腹和餐后eGFR的变化与GFR（碘海醇）和GFR（EDTA）的相应变化显著相关。eGFR预测GFR（EDTA）的准确性低于GFR（碘海醇）（标准差分别为19.9%和10.5%；P < 0.01）。尽管当GFR（EDTA）> 80 mL/min/1.73 m²时，eGFR与GFR（EDTA）相比相关性较差，但在不精密度或不一致性> 20%或30%方面没有显著差异。然而，当GFR（EDTA）> 80 mL/min/1.73 m²时，在更高比例的研究中，eGFR比GFR（碘海醇）更接近GFR（EDTA）（28/60），而当GFR（EDTA）< 80 mL/min/1.73 m²时，这一比例为9/37（P < 0.05）。
在预测GFR（EDTA）方面，eGFR不如GFR（碘海醇）。GFR（碘海醇）与GFR（EDTA）之间的不一致性表明GFR（EDTA）的不确定性对eGFR性能的影响程度。与较高GFR水平相比，eGFR在较低GFR水平时表现并无更好。
Zotero 插件