ICU患者血流感染早期诊断的临床研究

目的探讨血清降钙素原(PCT)、C反应蛋白(CRP)和D-二聚体(DD)联合检测对ICU患者血流感染早期诊断的价值。方法收集239例ICU患者同时进行血培养和PCT、CRP和DD检测,根据血培养结果分为血培养阳性(BC阳性)组和血培养阴性(BC阴性)组,分析其敏感度、特异度、阳性似然比、阴性似然比、阳性预测值、阴性预测值,应用受试者工作特性(ROC)曲线进行分析,评估PCT、CRP和DD在ICU患者血流感染早期诊断中的价值,并确定其Cut-off值。计算PCT、CRP和DD联合检测在ICU患者血流感染早期诊断中的敏感度和特异度。结果BC阳性组PCT、CRP和DD水平(中位数分别为0.60ng/mL、33.33mg/L和2 785.70ng/mL)均显著高于BC阴性组(中位数分别为0.09ng/mL、2.28mg/L和1 625.0ng/mL),差异有统计学意义(P0.01)。ROC曲线显示,PCT、CRP和DD的曲线下面积(AUC)分别为0.852、0.715和0.643,最佳诊断界点分别为0.405 0ng/mL、3.440 0mg/L和2 083.90ng/mL,其敏感度分别为0.775、0.875和0.656,特异度分别为0.825、0.525和0.629,阳性似然比分别为4.43、1.84和1.77,阴性似然比分别为0.27、0.24和0.55,阳性预测值分别为0.898 6、0.823 5和0.750 0,阴性预测值分别为0.647 1、0.714 3和0.511 6。PCT、CRP和DD联合检测敏感度为0.422,特异度为0.971。结论 PCT、CRP和DD对于ICU患者血流感染的早期临床诊断具有重要价值,三者联合检测能提高诊断的特异度。

Clinical research on early diagnosis of blood stream infection in ICU patients

Objective To investigate the value of combined detection of procalcitonin (PCT ) ,C reactive protein (CRP) and D‐dimmer(DD) in the early diagnosis of bloodstream infection of ICU patients .Methods A total of 239 ICU patients were collected and performed the blood bacterial culture(BC) and the detection of PCT ,CRP and DD .The patients were divided into the blood cul‐ture positive group(BC positive) and BC negative group(BC negative) according to the BC results .The sensitivity ,specificity ,posi‐tive likelihood ratio(LR+ ) ,negative likelihood ratio(LR-) ,positive predictive value(PV+ ) and negative predictive value(PV -) were analyzed .The receiver operating characteristic(ROC) curve was analyzed for evaluate the values of PCT ,CRP and DD in the early diagnosis of bloodstream infection .The cutoff value was determined .The sensitivity and specificity of combined detection of PCT ,CRP and DD in the early diagnosis of bloodstream infection of ICU patient were calculated .Results The median of PCT ,CRP and DD in the BC positive group were 0 .60 ,33 .33 ,2 785 .70 ng/mL respectively ,which were significantly higher than 0 .09 ng/m2 , 2 .28 ng/mL ,1 625 .00 ng/mL in the BC negative group ,the differences were statistically significant (P<0 .01) .The ROC curves showed that the areas under ROC curve(AUC) of PCT ,CRP and DD were 0 .852 ,0 .715 and 0 .643 respectively .The optimal diag‐nostic cut‐off values were 0 .405 8 ,3 .440 0 mg/L ,2 083 .90 ng/mL respectively .Their sensitivities were 0 .775 ,0 .875 and 0 .656 respectively ,specificities were 0 .825 ,0 .525 and 0 .629 respectively ,LR+ were 4 .43 ,1 .84 and 1 .77 respectively ,LR- were 0 .27 , 0 .24 and 0 .55 respectively ,PV+ were 0 .898 6 ,0 .823 5 and 0 .750 0 respectively and PV - were 0 .647 1 ,0 .714 3 and 0 .511 6 re‐spectively .The sensitivity and specificity of combined detection of PCT ,CRP and DD were 0 .422 and 0 .971 .Conclusion PCT ,CRP and DD have important value for the early diagnosis of bloodstream infection of ICU patients and their combined detection can im‐prove the specificity of diagnosis .