摘要
目的评价高黏液表型、毒力基因预测高毒力肺炎克雷伯菌(hvKp)的应用价值。方法收集2016年11月-2018年4月广东省4所医院分离的肺炎克雷伯菌,通过拉丝试验判断菌株黏液表型,检测毒力基因和血清型情况,采用蜡螟模型计算菌株的半数致死率(LD_(50)),比较不同高黏液(hm)表型和毒力基因型菌株LD_(50)。结果共收集194株肺炎克雷伯菌,拉丝试验阳性菌株占40.2%(78株)。蜡螟试验结果显示,仅毒力基因iuc A、iro B、fim H阳性菌株LD_(50)低于相应的阴性菌株(P<0.05)。iuc A+iro B+fim H+hm全阳性组(n=58)、iuc A阳性+iro B阳性+fim H阳性+hm阴性组(n=23)、iuc A+iro B+fim H+hm全阴性组(n=28)3组LD_(50)分别为(5.39±0.71)、(5.44±0.62)、(5.83±0.64)log10 CFU/mL,前两组比较差异无统计学意义(P=0.786),但前两组分别与第3组比较差异均有统计学意义(P<0.05)。在高黏液表型菌株中血清型K1、K2、K57检出率高于非高黏液表型菌株,差异均有统计学意义(均P<0.001)。结论仅依据高黏液表型预测hvKp准确性较低,与高黏液表型相比,毒力基因iuc A+、iro B+、fim H+预测hvKp更准确。
Objective To evaluate the application value of hypermucoviscous phenotype and virulence gene in predicting hypervirulent Klebsiella pneumoniae(hvKp).Methods Klebsiella pneumoniae isolated from four hospitals in Guangdong Province from November 2016 to April 2018 were collected,mucoviscous phenotypes were determined through string test,virulence genes and serotypes were detected,50%lethal rate(LD_(50))of strains was calculated by Galleria mellonella model,LD_(50)of strains of different hypermucoviscous phenotypes and virulence genes were compared.Results A total of 194 strains of Klebsiella pneumoniae were collected,40.2%(n=78)of which were positive for string test.Galleria mellonella test results showed that LD_(50)of only iuc A,iro B,and fim H positive strains was lower than that of corresponding negative strains(P<0.05).LD_(50)of strain group of all positive for iuc A+iro B+fim H+hm(n=58),iuc A positive+iro B positive+fim H positive+hm negative(n=23)and all negative for iuc A+iro B+fim H+hm(n=28)were(5.39±0.71),(5.44±0.62),and(5.83±0.64)lg10CFU/mL respectively,there was no significant difference between the first two groups(P=0.786),but there was significant difference between the first two groups and the third group(P<0.05),positive rates of serotypes K1,K2 and K57 in hypermucoviscous phenotype strains were significantly higher than those in non-hypermucoviscous phenotype strains,difference were all significant(all P<0.001).Conclusion Accuracy of the prediction of hvKp based only on hypermucoviscous phenotype is low,compared with hypermucoviscous phenotype,virulence genes iuc A+,iro B+and fim H+are more accurate to prediction hvKp.
作者
马明葱
李晓雨
卓超
MA Ming-cong;LI Xiao-yu;ZHUO Chao(Department of Respiratory Diseases,Dongguan People’s Hospital,Dongguan 523000,China;Department of Respiratory Diseases,First Affiliated Hospital of Guangzhou Medical University,Guangzhou 510000,China)
出处
《中国感染控制杂志》
CAS
CSCD
北大核心
2021年第11期1003-1007,共5页
Chinese Journal of Infection Control
基金
广州市科技重点项目(201607020044)。
