血清Cyst C用于判断早期肾功能损害的敏感性与特异性研究

目的:评价血清胱蛋白酶抑制剂C(Cyst C)用于判断早期肾功能损害的敏感性与特异性。方法:采用固定时间颗粒增强的免疫透射比浊法(PETIA)测定116例肾科住院病人血清CystC浓度,同时测定血清肌酐(Scr,酶法),以目前国内最常用的内生肌酐清除率(Ccr)推算肾小球滤过率(GFR)的方法为判断肾功能损害与否的指标,计算并比较血清CystC、Scr用于判断肾功能损害的敏感性与特异性。结果:血清CystC诊断肾小球滤过功能受损的敏感性为99%,特异性为40%。而Scr则与之相反,敏感性为80%,特异性为100%。结论:血清CystC诊断肾小球滤过功能受损的敏感性高于Scr,尤其是在早期肾脏损害时更敏感。血清CystC诊断肾小球滤过功能受损的特异性低于Scr,进一步表明在早期肾功能损害时,血清CystC结果已经反映出早期肾功能损害,而此时的Scr值尚不能反映出早期肾功能损害。血清CystC测定在早期预测肾功能损害的发生中有重要的价值。

Assessment of the Diagnostic Sensitivity and Specificity of Serum Cystatin C (Cyst C) Levels Determination in Patients with Early Stage Renal Function Impairment

Objective To assess the diagnostic applicability of serum Cystatin C (Cyst C) determination in patients with early renal function impairment. Methods Serum Cyst C concentrations were determined with particle enhanced (turbidity) immunonephelometric assay (PETIA) in 116 patients with various kinds of renal disorders. Serum creatinime (SCr) levels were also determined with biochemistry (enzyme method) and endogenous creatinine clearance (CCr) calculated. Results Compared with the conventional SCr(CCr) determination, the Cyst C test was far more sensitive (sensitivity 99% vs 80%) but much less specific (specificity 40% vs 100%). Conclusion Cyst C determination was very useful for early detection of renal function impairment due to its high sensitivity.