不同胱抑素方程对我国慢性肾脏病患者的适用性评估

Evaluation of cystatin C-based glomerular filtration rate estimation formulae in chronic kidney disease

目的评价在血清胱抑素C(Cys-C)含量基础上开发的肾小球滤过率(GFR)评估方程在我国慢性肾脏病(CKD)患者的适用性。方法选择2008年1月至2009年11月我院肾内科就诊的412例CKD患者,将简化MDRD方程、Cys-C方程1～5计算的GFR值与99mTc-DCPA测定的GFR(sGFR)进行比较。结果各方程计算的GFR与sGFR总体上均呈显著性相关(P<0.001),Cys-C方程4和Cys-C方程5估算的GFR与sGFR的一致性最佳,Cys-C方程4、5的准确性和精确度均高于其他方程。在CKD1～5期,Cys-C方程4、5的准确性高于其它方程(P<0.001)。所有方程中仅Cys-C方程5的偏差一致性限度在事先规定的专业界值60ml·min-1·1.73m-2之内。结论Cys-C方程4、5的准确性、精确度均优于以往的GFR评估方程,并在不同CKD分期病人中有较好的适用性。但该方程的一致性限度仍存在不足,有必要进行进一步的检验和方程,为临床提供更加准确和适用的肾功能评估方法。

Objective To evaluate the validity of the simplified Modification of Diet in Renal Disease formula （MDRD） and the formulae based upon cystain C （Cys-C） for estimation of glomerular filtration rate （GFR） in Chinese patients with chronic kidney disease（CKD）. Methods Serum creatinine and serum Cys-C were measured in 412 patients admitted in our hospital for determining the GFR by 99mTc-DTPA plasma clearance （sGFR） method betweeb January 2008 to November 2009, and the difference, limits of agreement, precision and accuracy were calculated. Result The estimated GFRs by all the formulae were significantly correlated to the sGFR （P0.001）. The Cys-C formulae 4 and 5 showed better consistence with sGFR than the other formulae. The Cys-C fomulae 4 had greater diagnostic precision and accuracy for predicting the renal function. Compared with the other formulae, the Cys-C formulae 4 and 5 had better accuracy in stages 1 to 5 CKD （P0.001）. However, Bland-altman analysis demonstrated that only the Cys-C formulae 5 was well consistent with sGFR, for the limits of agreement was within the professional agreement of 60 ml·min-1·1.73 m-2. Conclusion Compared with the MDRD equation, the Cys-C formulae 4 and 5 has greater advantages in predicting the GFR in Chinese CKD patients. However, the limits of agreement of the formula should be improved by large-sample clinical trials.