早期血清降钙素原对成人细菌性血流感染病原菌种属的鉴别价值

目的 探讨早期降钙素原水平对成人革兰氏阳性菌和革兰氏阴性菌的诊断意义以及对病原菌种属的鉴别价值。方法 抽取医院2014年5月-2017年11月血培养结果阳性病例,筛选出符合要求病历374份(革兰氏阴性菌286例,革兰氏阳性菌88例)；分组记录患者抽取血培养前后<12小时血清降钙素原(PCT)。采用受试者工作曲线(ROC曲线)分析早期PCT水平对革兰氏阴性菌和革兰氏阳性菌的诊断意义；并针对早期PCT水平对血流感染临床常见的革兰氏阴性菌四个种属病原菌(大肠埃希菌、肺炎克雷病菌、鲍曼不动杆菌及铜绿假单胞菌)和革兰氏阳性菌四个种属病原菌(凝固酶阴性葡萄球菌、金黄色葡萄球菌、肠球菌属及链球菌属)的鉴别价值,使用Kruskal-wallis检验进行多组间比较,以P<0.05为有显著性差异。结果 革兰氏阴性菌组PCT水平6.15(1.04-32.04)]显著高于革兰氏阳性菌组PCT水平0.59(0.23-3.11)]。ROC曲线下面积0.749,P<0.001；当以1.805ng/ml为界点时,对革兰氏阴性菌诊断的敏感性为70%,特异性为71.6%。在鉴别菌属价值方面：革兰氏阴性菌中,铜绿假单胞菌组PCT浓度水平显著高于鲍曼不动杆菌组(P=0.011)；革兰氏阳性菌中,链球菌属组PCT浓度水平显著高于凝固酶阴性葡萄球菌组(P=0.045),其它各组之间无统计学差异。结论 血流感染患者早期PCT水平对革兰氏阳性菌和革兰氏阴性菌的诊断效果显著,对病原菌种属的鉴别具有辅助作用。

Identification Value of Early Procalcitonin Levels in Pathogenic Bacteria Species of Bacterial Bloodstream Infection in Adults

ABSTRACT: OBJECTIVE To explore diagnostic significance of early procalcitonin(PCT) levels between gram-positive and gram-negative bacteria, as well as the differential value in pathogenic bacteria species. METHODS The positive cases of blood culture in the hospital between May 2014 and November 2017 were selected and 374 copies of the medical records were obtained after screening. Among them, there were 286 gram-negative and 88 gram-positive bacteria. Serum PCT levels (<12) hours before or after blood culture was recorded. A receiver operating characteristic curve (ROC curve) analysis was used to discriminate gram-negative from gram-positive bloodstream infections. The diagnostic value of early PCT levels at clinical common gram-negative bacteria species and gram- positive bacteria species(n=4 each) was tested by Kruskal-wallis, P<0.05 had significant difference. RESULTS PCT levels of gram-negative bacteria group 6.15 (1.04-32.04) was significantly higher than gram positive group 0.59 (0.23-3.11)]. The area under the ROC curve was 0.749, P<0.001. When the cutoff for PCT was 1.805ng/ml, the sensitivity and specificity of gram-negative bacteria infection was 70% and 71.6%, respectively. Among gram-negative bacteria, PCT level of Ascherichia coli group was significantly higher Acinetobacter baumannii group (P=0.011). Among gram-positive bacteria, PCT level of Streptococcus group was significantly higher than Coagulase negative Staphylococcus group (P=0.045). There was no statistical difference among other groups. CONCLUSION PCT level in early stage of bloodstream infection has significant effect on the diagnosis of gram-positive bacteria and gram-negative bacteria and plays a supporting role in identification for pathogenic bacteria species.