尿路感染B群链球菌的耐药特征与CAMP试验敏感性分析  

Analysis of drug-resistant characteristics of group B Streptococcus in urinary tract infection and sensitivity of CAMP test

作　　者：时翠销 王刚[1] 李亚娟 黄颖[1] 徐元宏[1] Shi Cuixiao;Wang Gang;Li Yajuan(Dept of Clinical Laboratory,The First Affiliated Hospital of Anhui Medical University,Hefei 230022)

机构地区：[1]安徽医科大学第一附属医院检验科,合肥230022

出　　处：《安徽医科大学学报》2021年第10期1516-1520,共5页Acta Universitatis Medicinalis Anhui

基　　金：国家自然科学基金(编号:81171606)。

摘　　要：目的研究尿路感染B群链球菌的耐药特点、耐药基因分布情况及CAMP试验敏感性和编码CAMP因子的cfb基因的表达情况。方法采用纸片扩散法和Vitek 2 Compact仪器法测定抗菌药物的敏感性,D试验检测红霉素诱导的克林霉素耐药,PCR法检测抗生素相关耐药基因;进行CAMP试验,通过检测16S rRNA基因片段及cfb基因、生化试验、基质辅助激光解吸电离飞行质谱(MALDI-TOF MS)鉴定菌株。结果51株B群链球菌对氨苄西林、达托霉素、利奈唑胺、呋喃妥因、青霉素、奎奴普丁/达福普汀、替加环素、万古霉素耐药率为0,对红霉素、四环素、克林霉素、左氧氟沙星、莫西沙星、环丙沙星耐药率分别为66.7%、66.7%、49.0%、47.1%、49.0%、47.1%。红霉素和四环素主要耐药基因为ermB和tetM,喹诺酮类抗生素耐药基因gyrA和parC,它们的检出率均为78.4%。CAMP试验结果显示3株阴性、9株弱阳性、39株阳性,经生化试验、cfb基因、16S rRNA检测、MALDI-TOF MS鉴定,除2株阴性株及2株弱阳性株未检测出cfb基因,其余方法鉴定均符合为B群链球菌的特征。结论尿路感染的B群链球菌对多种抗生素敏感,对红霉素、克林霉素、四环素、喹诺酮类抗生素耐药性高,耐药基因携带情况与耐药性具有一定相关性;CAMP试验及cfb基因对于B群链球菌的鉴定缺乏敏感性。Objective To study the drug-resistant characteristics of group B Streptococcus in urinary tract infection,the distribution of drug resistance genes and sensitivity of CAMP test and the cfb gene expression.Methods The sensitivity of antimicrobial agents was determined by disk diffusion method and Vitek 2 Compact instrument analysis.The erythromycin induced clindamine resistance was detected by D test.The antibiotic resistance genes were detected by PCR.CAMP test was conducted and strains were identified by detecting 16S rRNA gene fragments and the cfb gene,biochemical test and MALDI-TOF MS.Results The drug resistance rates of 51 strains of group B Streptococcus to ampicillin,doxycycline,rina thiazole amine,nitrofurantoin,penicillin and quinupristin/dalfopristin,tigecycline,vancomycin were 0,while the drug resistance rates to erythromycin,tetracycline,clindamycin,levofloxacin,moxifloxacin,and ciprofloxacin were 66.7%,66.7%,49.0%,47.1%,49.0%,and 47.1%,respectively.The main erythromycin and tetracycline resistance genes were ermB and tetM respectively,and quinolones resistance genes were gyrA and parC and their detection rate was all 78.4%.The results of CAMP test showed that 3 strains were negative,9 strains were weakly positive and 39 strains were positive.Combined with biochemical tests,cfb gene,16S rRNA detection and MALDI-TOF MS identification results,all 51 strains were group B Streptococcus.However,cfb genes of 2 CAMP-negative strains and 2 weakly positive strains were not detected.Conclusion Group B Streptococcus in urinary tract infection is sensitive to a variety of antibiotics,but highly resistant to erythromycin,clindamycin,tetracycline and quinolone antibiotics.There is a certain correlation between drug-resistant gene and drug resistance.CAMP test and cfb gene expression are not sensitive to the identification of group B Streptococcus.

关 键 词：尿路感染 B群链球菌 耐药性 CAMP试验 

分 类 号：R378.12[医药卫生—病原生物学] R446.5[医药卫生—基础医学]