COBIO XS尿沉渣分析仪在尿路感染筛查中的应用

Evaluation of COBIO XS automated urine sediment analyzer in screening urinary tract infection

目的评价COBIO XS尿沉渣分析仪在尿路感染中的应用。方法应用COBIO XS尿沉渣分析仪检测182例疑似尿路感染中段尿标本白细菌和细菌数,以定量尿细菌培养作为诊断尿路感染金标准,应用受试者工作特性(ROC)曲线评价各指标诊断效能。结果尿培养阳性标本56例占30.8%,分离率依次为大肠埃希菌30株占53.6%、肠球菌属9株占16.1%、变形杆菌属6株占10.7%。白细胞计数曲线下面积为0.808(95%CI 0.710～0.867),当白细胞临界值为50/μL,诊断尿路感染敏感度89.0%,特异度83.8%,阳性预测值86.3%,阴性预测值93.7%。细菌计数曲线下面积为0.899(95%CI 0.797～0.923),当细菌临界值为110/μL,诊断尿路感染敏感度82.5%,特异度85.6%,阳性预测值78.5%,阴性预测值88.0%。结论 COBIO XS尿沉渣分析仪具有快速、准确等优点,可作为筛查尿路感染工具。

Objective To evaluate the clinical application of COBIO XS automated urine sediment analyzer for screening urinary tract infection（UTI）.Methods Midstream urine samples were collected from 182 patients with suspected UTI.White blood cell counts（WBC）and bacteria counts（BACT）were determined by COBIO XS automated urine sediment analyzer.By comparing with quantitative urine culture as the golden standard of UTI.The area under the ROC curve（AUC）was constructed to evaluate the discriminative power of variables to predict UTI.Results The positive rate of urine culture was 30.8%.The isolated rate of Escherichia coli,Enterococcus species and proteus species were 53.6%,16.1%,10.7%,respectively.ROC curve analysis showed that AUC was 0.808（95%CI0.710-0.867）for WBC and 0.899（95%CI 0.797-0.923）for BACT.The best cutoff value for WBC was 50/μL,sensitivity was 89.0%,specificity was 83.8%,positive predictive value was 86.3% and negative predictive value was93.7%.The best cutoff value for BACT was 110/μL,sensitivity was 82.5%,specificity was 85.6%,positive predictive value was78.5%and negative predictive value was 88.0%.Conclusion COBIO XS analyzer is adopted to conduct rapid and reliable a screening tool for UTI.