The issue of whether ^99mTc-DTPA can replace ⁵¹Cr-EDTA for measurement of plasma clearance as a surrogate for glomerular filtration rate (GFR) is of great relevance to daily clinical practice. Prompted by the shortage of ⁵¹Cr-EDTA we conducted a head-to-head comparison in patients attending our department for GFR determination. The two tracers (3.7 MBq of ⁵¹Cr-EDTA and 8 MBq of ^99mTc-DTPA) were administered intravenously immediately after each other, and the standard number of blood samples were drawn. Fifty-four patients were enrolled. In 51 of these, single-sample measurement was performed with the following results: GFR_EDTA was 84.6 ± 23.3 mL/min, GFR_DTPA was 84.2 ± 24.7 mL/min. The mean difference was 0.4 ± 2.8 mL/min, p = 0.32, and results based on the two tracers were highly correlated (r = 0.995). GFR_DTPA exceeded GFR_EDTA at high GFR values (difference < 0 at GFR_EDTA >91.4 mL/min) and vice versa (difference > 0 at GFR_EDTA < 91.4 mL/min). However, differences fell within few GFR units that most often will have no clinical consequence. We therefore conclude that ^99mTc-DTPA can replace ⁵¹Cr-EDTA for single-sample determination of GFR in a clinical setting.

^99m Tc-DTPA是否可以代替⁵¹ Cr-EDTA来测量血浆清除率，以此作为肾小球滤过率（GFR）的替代品，这一问题与日常临床实践密切相关。由于缺乏⁵¹ Cr-EDTA，我们对参加我们科室测定GFR的患者进行了正面对比。彼此立即静脉内施用两种示踪剂（3.7 MBq的⁵¹ Cr-EDTA和8 MBq的^99m Tc-DTPA），并抽取标准数量的血样。入选了54例患者。在其中的51个样品中，单样品测量结果如下：GFR _EDTA为84.6±23.3 mL / min，GFR _DTPA为84.2±24.7mL / min。平均差异为0.4±2.8 mL / min，p  = 0.32，基于两种示踪剂的结果高度相关（r  = 0.995）。在高GFR值下（GFR _EDTA > 91.4 mL / min时差值<0），GFR _DTPA超过GFR _EDTA，反之亦然（在GFR _EDTA <91.4 mL / min时差值> 0 ）。但是，差异落在几个GFR单位内，大多数情况下不会产生临床后果。因此，我们得出结论，在临床环境中，^99m Tc-DTPA可以代替⁵¹ Cr-EDTA用于单样本测定GFR。