【作者】 李克鹏；

【导师】 陆士奇；

【作者基本信息】 苏州大学 ， 急诊医学， 2009， 硕士

【摘要】 目的探讨血清胱抑素C(SCysC)作为肾小球滤过率标志物在诊断急性肾损伤中的价值。方法本研究共纳入ICU患者共46例,男36例(78%),女10例(22%),年龄( 56.2土18(20-80))岁。对每例入住ICU的患者于入院当日采静脉血1.5 mL保存,测血清肌酐作为基线资料。此后,每日检测血清肌酐,并密切观察尿量变化。对按标准诊断为AKI的患者,每日清晨8:00采静脉血1.5 mL,3000转离心10分钟后留取血清并保存于-70℃冰箱,直至患者出院、转科、行RRT治疗或死亡。将肌酐值最大日的标本集中测量SCysC。采用酶法测定血清肌酐。采用酶免法(ELISA)测SCysC。肌酐清除率(Ccr)采用Cockroft--Gault公式计算,以此作为GFR的估计值。应用SPSS 13.0统计软件对数据进行统计处理。计量资料以( x土s)表示,两组均数的比较用t检验;计数资料用百分率表示,应用X2 (卡方)检验;正常人中各项指标的95%参考值范围表示为( x土2s);相关关系采用Pearson相关系数和一元线性回归分析;运用ROC分析曲线评价SCysC诊断AFR的准确性、敏感性和特异性,并且寻找SCysC的最佳截断值;应用多元线性回归分析影响SCysC浓度的因素。结果发生急性肾损伤的46例患者处于1,2,3期的患者分别为19,11和16例。71名健康人作为对照组。在急性肾损伤患者中SCysC较正常组明显升高(P<0.01);46例AKI患者血清SCysC与Scr成显著线性相关,相关系数(r=0.877,p<0.01); 46例AKI患者( SCysC ) -1与eGFR成显著线性相关,相关系数R=0.924,p<0.01,回归方程eGFR=-32.15+150.003(SCysC)-1或(SCysC)-1 =0.24+0.006eGFR。以患者Scr升高1.5倍作为AKI诊断标准,由ROC曲线可以看出SCysC在AKI的诊断中,曲线下面积为0.949,95%可信区间为(0.890-1.008,p<0.01)。以估算的eGFR<=60 ml/min/1.732作为AKI的诊断标准,由ROC曲线可以看出SCysC在AKI的诊断中,曲线下面积为0.970,95%可信区间为(0.964-1.014,p<0.01) ,最佳截断值为1.832 mg/l,敏感性和特异性分别为97.4%和100%。以此标准由ROC曲线可以看出Scr在AKI的诊断中,曲线下面积为0.925,95%可信区间为(0.934-1.022,p<0.01),最佳截断值为123.5μmol/l,敏感性和特异性分别为93.4%和100%,两者AUC差别有统计学意义。以估算的eGFR<=60 ml/min/1.732作为AKI的诊断标准,将第1期患者比较发现Scr在AKI的诊断中,曲线下面积为0.864,95%可信区间(0.791-1.066,p<0.01), SCysC在AKI的诊断中,曲线下面积为0.932,95%可信区间为(0.885-1.044,p<0.01),两者比较有显著差异性。以最佳截断值评价诊断效能,发现SCysC准确性(88.7%v82%)、阳性及阴性预测值较Scr高,两者总体敏感性(Sen)、特异性(Spe)无明显差异。根据求得的正常人群各项检测指标,采用参考值范围上限(SCysC为1.7 mg/l,Scr为133μmol/l )为截断值,求得两指标的灵敏度,发现所有患者CysC(95.7%)及第一期患者CysC(89.5%)的灵敏度要明显优于所有患者Scr (82.6%)及第一期患者Scr(57.9%)。SCysC浓度的变化主要受Ccr的影响,而与患者的年龄、性别、体重、血糖、血红蛋白、总胆红素、血清蛋白、血前白蛋白等因素无关。结论在ICU内SCysC可以作为急性肾损伤患者GFR的内源性标志物,SCysC能较Scr更敏感、更及时地发现AKI患者肾功能的早期损害。更多还原

【Abstract】 Objective:To evaluate the feasibility and clinical value of serum cystatinC in assessing glomerular filtration rate in patients with acute kidney injury.Methods:Fourty-six acute kidney injury (36male/10female), aged 56.2土18 years in intensive care unit were recruited in the study and blood saples were collected daily. Serum creatinine(Scr)was measured by enzymic method.Cys C was detected by ELISA(Enzyme-Linked Immunoadsorbent Assay) and glomemlar filtration rate(GFR)was estimated by Cockrofi—Gault equation.AKI was diagnosed according to ADQI(RIFLE) criteria.The correlations among SCysC, Scr and Ccr were compared by using pearson correlation analysis. Multiple regression analysis was also used to understand the influential factors to the SCysC concentration. In order to compare the diagnostic value of SCysC and Scr, the Receiver Operating Charateristic curve(ROC) was calculated and sensitivity(Sen), specificity (Spe), accuration(Acc) of SCysC and Scr were obtained and analyzed. All data were analyzed by using statistical software of SPSS13.0.Result:46 patients developed AKI to some degree,among which 19,11and 16patients fulfilled staging 1 ,staging 2 ,and staging 3 respectively. 71 patients without AKI served as controls.In patients with AKI,Cys C was significantly increased than that in patients who did not develop AKI(P<0.01). Serum Cys C was linearly correlated with serum creatinine(r=0.877,P<0.01),also[CysC]-1 with estimated GFR (R=0.924,P<0.01). when AKI was diagnosed according to eGFR<=60 ml/min/1.732,with the staging 1 patients serum Cys C was demonstrated a highly diagnostic value to detect AKI ,The area under the curve(AUC)of the ROC for SCysC was 0.932(95%confidence interval,0.885-1.044,p<0.01) and The area under the curve(AUC)of the ROC for SCr was 0.864(95% confidence interval,0.791-1.066,p<0.01), there are significant statistical differentce between SCysC and Scr (P<0.01).With total patients there is also signifence difference. At a cutoff of 1.832mg/L, SCysC reached a 88.7% ACC, while at a cutoff of 123.5 umol/L, Scr has a 82% ACC ,there are significant statistical differentce between SCysC and Scr (P<0.05). The sensitivities were 95.7% for CysC and 82.6% for Scr with total patients, the sensitivities were 89.5% for CysC and 57.9% for Scr with staging 1 patients, there are significant statistical differentce between SCysC and Scr. The concentration of SCysC is not affected by age, gender, body weight, hemoglobin, serum protin, glucose,total bilirubin .Conclusions:Cystatin C can be one of the early detection markers of AKI.Serum cystatin C is superior to serum creatinine as a predictive marker of AKI in an early stage.更多还原