半胱氨酸蛋白酶抑制剂C在评价老年人肾小球滤过功能中的应用价值

目的探讨血清半胱氨酸蛋白酶抑制剂C(Cystatin C)对评价老年人肾小球滤过功能的临床应用价值.方法采用胶乳颗粒增强的免疫散射浊度法测定189例患各种肾脏病及相关疾病60岁以上老年患者的血清Cystatin C水平,同时测定了他们的血清肌酐及肌酐清清除率(Ccr),分别对血清Cystatin C和血清肌酐与肌酐清除率进行相关性分析.结果老年患者的血清Cystatin C与肌酐有显著正相关(P＜0.001),与Ccr的对数呈显著负相关(P＜0.001),回归方程分别为:Cystatin C=0.0112 Cr 0.2604(r=0.92)和Cystatin C=-3.406logCcr 7.593(r=-0.814).当Ccr(50～80)ml/min时,Cystatin C异常率(77.9%)高于肌酐异常率(9.1%).结论血清Cystatin C可作为老年人肾小球滤过功能指标,并可能比肌酐更能真实地反映老年人的肾小球滤过功能.

Evaluation of serum Cystatin C in elderly patients as a marker for renal filtration function

Objective:To study the clinical significance of serum Cystatin C in evaluation of renal filtra-tion function in elderly patients.Methods:A particle-enhanced nephelometric immunoassay(PENIA)was used to measure concentration of serum cystatin C.We determined the correlation between cystatin C and levels of serum creatinine(Scr)and creatinine clearance(Ccr)in189cases of elderly patients.Results:There was a significant positive correlation between serum cystatin C and serum creatinine level(r=0.92,P<0.001).Signif-icant negative correlation was observed between serum cystatin C and logCcr(r=-0.814,P<0.001).When Ccr was50~80ml/min,the abnormal rate of cystatin C(77.9%)was far higher than that of creatinine(9.1%).Conclusions:Serum cystatin C seems to be an attractive alternative and more accurate than serum creatinine for the estimation of GFR in elderly patients.