血清半胱氨酸蛋白抑制剂C在肾病早期诊断中的价值

目的:探讨半胱氨酸蛋白抑制剂C(Cystatin C)在早期诊断肾病中是否优于血清肌酐(Scr)和肌酐清除率(Ccr)。方法:收集我院58例肾病患者和63例2型糖尿病患者的血清和尿液标本。以99mTc-DTPA清除率测得的肾小球滤过率(GFR)作为诊断的金标准,同时用酶法测血清肌酐水平;用颗粒增强透射免疫比浊法(PENIA)检测血清半胱氨酸蛋白酶抑制剂C水平,比较半胱氨酸蛋白酶抑制剂C、血清肌酐、肌酐清除率与肾小球滤过率的相关性。结果:随着肾功能的减退,血清半胱氨酸蛋白酶抑制剂C和血清肌酐值逐渐升高,肌酐清除率值逐渐下降;半胱氨酸蛋白酶抑制剂C与血清肌酐、肌酐清除率均有相关性,在肾功能正常组(Ccr≥80ml/min)的患者中,有47%(35/74)的半胱氨酸蛋白酶抑制剂C水平大于正常人参考值上限,肌酐清除率<80ml/min组,半胱氨酸蛋白酶抑制剂C升高率达96%(45/47);而血血清肌酐在正常组无一例升高,仅1例在轻度下降组(60≤Ccr<80ml/min,n=22)中升高。结论:半胱氨酸蛋白酶抑制剂C是一种较理想的反映肾小球滤过率的血清标志物。半胱氨酸蛋白酶抑制剂C可以作为肾病的诊断指标,在肾病的诊断时间较血清肌酐更早,可作为肾病的早期预测指标之一。

The Early Diagnosis Value of Cystatin C in Renal Impairment

Objective To study the early diagnosis value of cystatin C in the renal impairment.Methods The study was performed on 58 renal impairment patients and 63 type 2 diabetic patients. And GFR as the golden standard was estimated by plasma clearance of 99m Tc-DTPA, serum creatinine (Scr) and cystatin C were detected by enzymic method and particle-enhanced turbidimetric immunoassay (PETIA),then studied the relationship between Cystatin C、Scr、Ccr and GFR.Results With the decrease of the renal function,the degree of serum cystatin C and Scr were found to increase with decreasing degree of Ccr. Scr and Ccr were all correlated with cystatin C concentration significantly. The correlation of Cys C and Ccr was superior to that of others and Scr. In patients with normal renal function,there were 47 percent patients’ degree of serum cystatin C preponderate over the upper limit of normal person; and there were 96 percent patients preponderate over the upper limit of normal person in patients with abnormal. But in patients with normal renal function, there was no persons’ degree of serum creatinine over the upper limit of normal person, and only one persons’ degree of serum creatinine over the upper limit of normal person.Conclusion Serum Cystatin C is a more sensitive and specific marker for GFR, Serum Cystatin C is superior to serum creatinine as a predictive marker of renal impairment in an early stage. Cystatin C can be one of the early detection markers of renal impairment.