Pöge Uwe, Gerhardt Thomas, Stoffel-Wagner Birgit, Palmedo Holger, Klehr Hans-Ulrich, Sauerbruch Tilman, Woitas Rainer P
Department of Internal Medicine I, University of Bonn, Bonn, Germany.
Clin Transplant. 2006 Mar-Apr;20(2):200-5. doi: 10.1111/j.1399-0012.2005.00466.x.
To overcome disadvantages of serum creatinine two strategies have been suggested to identify patients with reduced glomerular filtration rate (GFR). On the one hand, the Modification of Diet in Renal Disease (MDRD) equation is now recommended to classify the stage of chronic kidney disease. On the other hand, cystatin C (Cys C) has been investigated in numerous studies, finding a higher sensitivity than creatinine in detecting diminished GFR. To date, no comparison of both strategies in patients after renal transplantation has been performed.
One hundred and five consecutive renal transplant recipients underwent (99m)Tc-DTPA-- clearance measurement. Simultaneously, MDRD estimates were calculated and Cys C serum levels were determined. ROC analyses were performed at different decision points from 20 to 70 mL/min/1.73 m(2).
Although the area under the curve did not differ significantly between MDRD and Cys C within the tested GFR range, the AUC for Cys C tended to be higher when GFR exceeded 55 mL/min/1.73 m(2). A significantly higher diagnostic accuracy for Cys C compared with MDRD (p = 0.045 at 65 mL/min/1.73 m(2)) was found when investigating the subgroup of patients with well-functioning grafts (GFR>40 mL/min/1.73 m(2)).
MDRD equation is equivalent to Cys C measurement in renal transplant recipients. As availability of MDRD is superior to Cys C, we recommend GFR estimation using the MDRD equation. Nevertheless, Cys C may serve as a confirmation test of high MDRD estimates in patients with well-functioning grafts because of superior accuracy in these patients.
为克服血清肌酐的缺点，已提出两种策略来识别肾小球滤过率（GFR）降低的患者。一方面，目前推荐使用肾脏病饮食改良（MDRD）方程来对慢性肾脏病的分期进行分类。另一方面，胱抑素C（Cys C）已在众多研究中得到调查，发现在检测GFR降低方面其敏感性高于肌酐。迄今为止，尚未对肾移植术后患者的这两种策略进行比较。
对105例连续的肾移植受者进行了（99m）Tc-DTPA清除率测量。同时，计算MDRD估算值并测定Cys C血清水平。在20至70 mL/min/1.73 m²的不同决策点进行ROC分析。
尽管在测试的GFR范围内，MDRD和Cys C的曲线下面积无显著差异，但当GFR超过55 mL/min/1.73 m²时，Cys C的AUC往往更高。在研究移植肾功能良好（GFR>40 mL/min/1.73 m²）的患者亚组时，发现Cys C的诊断准确性显著高于MDRD（在65 mL/min/1.73 m²时p = 0.045）。
在肾移植受者中，MDRD方程与Cys C测量等效。由于MDRD的可用性优于Cys C，我们建议使用MDRD方程估算GFR。然而，由于Cys C在这些患者中的准确性更高，它可作为移植肾功能良好患者中MDRD高估算值的确认试验。
