降钙素原与中性粒细胞淋巴细胞计数比值在COPD急性加重期细菌感染的诊断价值

Clinical value of procalcitonin and neutrophil-lymphocyte ratio in diagnosis of bacterial infection in patients with acute exacerbations of COPD

目的探讨降钙素原(PCT)与中性粒细胞淋巴细胞计数比值(NLR)在慢性阻塞性肺病(COPD)急性加重期细菌感染的诊断价值,为其临床研究提供参考依据。方法选择2015年3月-2016年5月188例怀疑细菌感染的COPD急性加重期患者作为研究对象,所有患者均空腹抽取静脉血检测PCT及NLR值;以痰液培养结果为金标准,采用ROC曲线分析PCT及NLR单独与联合对COPD急性加重期细菌感染的诊断价值。结果 188例怀疑细菌感染的COPD急性加重期患者中,痰培养细菌感染146例占77.7%,非细菌感染42例占22.3%;细菌组WBC、NEUT、NLR及PCT均高于非细菌组,差异有统计学意义(P<0.05);以痰培养结果为金标准绘制ROC曲线发现,WBC的AUC面积为0.614,截断值为10.39,灵敏度为47.9%,特异度为52.4%;NEUT的AUC面积为0.637,截断值为0.63,灵敏度为50.0%,特异度为59.5%;NLR的AUC面积为0.776,截断值为2.10,灵敏度为81.5%,特异度为71.4%;PCT的AUC面积为0.898,截断值为0.97,灵敏度为89.0%,特异度为85.7%;PCT联合NLR并联漏诊率最低为2.0%,PCT联合NLR串联误诊率最低为4.1%。结论 PCT并联NLR诊断COPD急性加重期细菌感染的漏诊率较低。

OBJECTIVE To explore the clinical value of procalcitonin（PCT）and neutrophil-lymphocyte ratio（NLR）in diagnosis of bacterial infection in patients with acute exacerbations of chronic obstructive pulmonary disease（COPD）so as to provide guidance for clinical research.METHODS From Mar 2015 to May 2016,a total of188 acute exacerbations of COPD patients with suspected bacterial infection were recruited as the study objects,the fasting venous blood was drawn from all of the enrolled patients so as to detect the PCT and NLR,the result of the sputum culture was set as the golden standard,and the value of single PCT,NLR,or their combination in diagnosis of the bacterial infection in the patients with acute exacerbations of COPD was evaluated by means of ROC curve analysis.RESULTS The result of sputum culture showed that of the 188 acute exacerbations of COPD patients with suspected bacterial infection,146（77.7%）had bacterial infection,and 42（22.3%）had non-bacterial infection.The levels of WBC,NEUT,NLR,and PCT were higher in the bacterial group than in the non-bacterial group,and there was significant difference（P〈0.05）.The ROC curve that was drawn based on the sputum culture result revealed that the AUC of the WBC was 0.614,the cutoff value 10.39,the sensitivity 47.9%,the specificity 52.4%;the AUC of the NEUT was 0.637,the cutoff value 0.63,the sensitivity 50.0%,the specificity 59.5%;the AUC of the NLR was 0.776,the cutoff value 2.10,the sensitivity 81.5%,the specificity 71.4%;the AUC of the PCT was 0.898,the cutoff value 0.97,the sensitivity 89.0%,the specificity 85.7%.The rate of missed diagnosis of the PCT combined with NLR in parallel was the lowest（2.0%）,and the misdiagnosis rate of the PCT combined with NLR in series was the lowest（4.1%）.CONCLUSIONThe rate of missed diagnosis of the PCT combined with NLR in parallel is relatively low in the diagnosis of bacterial infections in the patients with acute exacerbations of COPD.