光抑素C与血肌酐对2型糖尿病患者肾小球滤过功能评价比较

目的 比较光抑素C(Cystatin C)和血清肌酐及8小时肌酐清除率，评价其对2型糖尿病患者肾小球滤过率(GFR)的判断价值。方法 选择80例2型糖尿病患者，检测其血肌酐、肌酐清除率、尿微量白蛋白排泌率(UAER)及Cystatin C水平，同时通过^99mTc-DTPA排泌率，应用Gates法计算GFR。结果 Cystatin C水平随GFR下降逐渐升高。相关性分析示Cystatin C与GFR呈相关性(r=-0．663，p=0．000)，明显高于肌酐(r=-0．444，P=0．009)及8小时肌酐清除率(r=0．300，P=0．000)。ROC曲线分析示Cystatin C具有更大的曲线下面积(AUC)，敏感性(82％)、特异性(96％)均好，而肌酐特异性好(98％)、敏感性差(20％)，8小时肌酐清除率敏感性(68％)、特异性(79％)均不理想。Cystatin C诊断精确性(80％)明显高于肌酐(63％)。结论 Cystatin C是反映GFR的更敏感指标，可更早、更准确地反映2型糖尿病患者GFR的变化。

The comparison of cystatin C and serum creatinine for estimating glomerular filtration function in type 2 diabetic patients

Objective To test the value of serum cystatin C and serum creatinine to glomerular filtration rate(GFR) in type-2 diabetic patients by comparing cystatin C and serum creatinine as well as 8h creatinine clearancerate. Methods Cystatin C,Serum creatinine, creatinine clearance rate and urine albumin excretion rate(UAER) were measured in 80 type 2 diabetic patients.GFR was estimated by the clearance of 99mTc-DTPA and calculated by Gates formula. Results Cystatin C concentration progressively increased as GFR decreased. The correlation between Cystatin C and GFR(r=-0.663,P=0.000) was stronger than that between creatinine and GFR(r=-0.444,P=0.009) and between 8 hours creatinine clearance rate and GFR(r=0.300,P=0.000). ROC curve analysis demonstrated that the area under the curve(AUC) of Cystatin C was greater than that of creatinine and 8 hours creatinine clearance rate, and cystatin C was more sensitive and specific, 82% and 96%, respectively, while the specificity of creatinine was better(98%),but the sensitivity was worse (20%), and the sensitivity and specificity of 8h creatinine clearance rates were not statisfactory, 68% and 79%, respectively. The diagnostic accuracy(80%)of cystatin C was higher than that of creatinine(63%). Conclusion Cystatin C is a more sensitive serum marker for early and accurat estimation of GFR in type 2 diabetes patients.