血培养污染菌判定的实验室检查  

Labortory diagnosis of blood culture contamination bacteria

作　　者：王露霞[1] 石凌波[2] 郭振辉[3] 陈蕊[3] 胡慧灵[4] 李建勋[1] 李薇[1] 张凤川[5] 

机构地区：[1]广州军区广州总医院检验科,广东广州510010 [2]广州中医药大学祈福医院检验科,广东广州510049 [3]广州军区广州总医院MICU-广东省老年感染与器官功能支持重点实验室,广东广州510010 [4]中山大学2008级医学检验系,广东广州510080 [5]广州军区联勤部门诊部检验科,广东广州510080

出　　处：《热带医学杂志》2015年第6期744-747,802,共5页Journal of Tropical Medicine

基　　金：广东省科技计划项目(2012A061400010);广州市科研条件建设项目(穗科信字2012 224-5号)

摘　　要：目的探讨鉴别血培养致病菌和污染菌的有效指标,为快速检测血流感染病原菌提供依据。方法回顾性分析2012年血培养阳性患者的临床和实验室资料,将患者分为血流感染组(n=70)和血培养污染组(n=30),比较两组患者年龄、体温、心率、收缩压、呼吸频率、白细胞总数、血培养阳性报警时间(TTP)、C-反应蛋白(CRP)、降钙素原(PCT)水平差异,通过多因素统计分析,排除可能的混淆因素影响,获得相关预测因素,绘制受试者工作特征曲线(ROC曲线),评价预测因素对于对血流感染和血培养污染的鉴别能力。结果血培养污染菌群分布中以凝固酶阴性葡萄球菌为主,占73.3%(22/30);在9项指标中,仅TTP、CRP、PCT三项指标与判断血培养污染有关;TTP、CRP、PCT三者ROC曲线下面积分别为0.838、0.736和0.927。当TTP≥17.7 h时,诊断血培养污染的敏感性、特异性、阳性预测值、阴性预测值分别为93.3%、65.7%、53.8%和95.8%;CRP≤51.7 mg/L时,诊断血培养污染的敏感性、特异性、阳性预测值、阴性预测值分别为76.7%、64.3%、47.9%和86.6%;PCT≤0.5 ng/ml时,诊断血培养污染的敏感性、特异性、阳性预测值、阴性预测值分别为96.7%、84.3%、72.5%和98.4%;三项指标联合时,诊断血培养污染的敏感度、特异性、阳性预测值、阴性预测值分别为70.0%、98.6%、95.5%和88.5%。结论 TTP、CRP和PCT联合检测对鉴别血流感染和血培养污染的诊断意义优于单项指标。结合病人临床相关资料,能得到更加准确的诊断。Objective To identify effective index of the blood culture pathogenic bacteria and the contamination bacteria,for clinical quickly and correctly detect the bloodstream infections pathogens. Methods 100 blood culture positive cases from 2011-2012 were collected from the patient＇s clinical and laboratory data after eliminating single blood culture.According to the established standard,patients were divided into bacteremia and blood culture contamination group. The age, body temperature, heart rate and systolic blood pressure, breathing rate, total number of white blood cells, blood culture positive for alarm time（TTP）, C-reactive protein（CRP） and procalcitonin（PCT） were analyzed. Eliminate possible confounding factors influenced by statistic analysis of multiple factors, the prediction factors were identified, and then the receiver-operating characteristic curve（ROC curve） was drawn. The diagnostic ability of bloodstream infections and blood culture contamination was evaluated. Results Coagulase negative staphylococcus bacteria were the main pathogen in blood culture contamination, accounted for 73.3%; In nine analyzed indicators, only TTP, CRP and PCT three indicators related to judge the blood culture contamination; For TTP ≥17.7 h, the sensitivity, specificity, positive predictive value, negative predictive value of diagnosis blood culture contamination were 93.3%, 65.7%, 53.8% and95.8%, respectively; for CRP ≤51.7 mg / L, the sensitivity, specificity, positive predictive value, negative predictive value of diagnosis blood culture contamination were 76.7%, 64.3%, 47.9% and 86.6%, respectively; for PCT≤0.5 ng / ml,the sensitivity, specificity, positive predictive value, negative predictive value of diagnosis blood culture contamination were 96.7%, 84.3%, 72.5% and 98.4%, respectively. Combined above three indicators, the sensitivity, specificity,positive predictive value, negative predictive value of diagnosis blood culture contamination were 70.0%, 98.6%, 95.5%and 88.5%, respectively. Con

关 键 词：血培养阳性报警时间 C-反应蛋白 降钙素原 污染菌 血流感染 

分 类 号：R446.5[医药卫生—诊断学]