摘要
目的:探讨婴幼儿无乳链球菌(GBS)耐红霉素类药物的耐药基因谱与血清型分布机制。方法:选取2022年5月—2023年6月深圳市南山区人民医院检出的93株菌株,来源于婴幼儿及妊娠35~37周孕产妇,样本涵盖血液、脑脊液、呼吸道分泌物等多种临床标本类型。通过标本采集与处理、GBS分离鉴定、药物敏感性测试、基因分型与耐药基因检测以及统计分析等方法,对GBS的耐药基因谱与血清型分布机制进行深入研究。结果:在耐药基因检测中,78株检出erm(B)基因,检出率为83.9%;65株检出mef(A)基因,检出率为70.0%;且有60株同时检出erm(B)和mef(A)基因,检出率为64.5%。不同血清型的GBS在耐药基因携带情况上存在显著差异,血清型Ⅲ和Ⅰa的GBS对红霉素的耐药率较高。基因分型结果显示,ST-17型GBS对红霉素耐药率高达92.3%,且均携带erm(B)基因,85.7%同时携带mef(A)基因。结论:婴幼儿GBS的耐药基因谱复杂多样,主要耐药机制包括靶位点修饰和药物外排,其中erm(B)基因和mef(A)基因是主要的耐药基因。不同血清型的GBS存在不同的耐药基因携带模式,且特定血清型与耐药基因之间存在紧密关联。
Objective:To investigate the mechanisms underlying the distribution of erythromycin resistance genes and serotypes in Group B Streptococcus(GBS)isolates from infants and young children.Methods:93 GBS-positive infants and pregnant women at 35~37 weeks gestation identified at Shenzhen Nanshan District People's Hospital from May 2022 to June 2023were enrolled as study subjects.Samples encompassed multiple clinical specimen types including blood,cerebrospinal fluid,and respiratory secretions.The drug resistance gene spectrum and serotype distribution mechanisms of GBS were investigated in depth through specimen collection and processing,GBS isolation and identification,drug susceptibility testing,genotyping and drug resistance gene detection,and statistical analysis.Results:The resistance rates of GBS in infants and young children to erythromycin and clindamycin were 82.8%and 74.2%,respectively.Among pregnant women and mothers,GBS exhibited resistance rates of 91.1%to tetracycline and 58.9%to clindamycin.In resistance gene detection,78 strains were detected the erm(B)gene(83.9%detection rate),65 strains were detected the mef(A)gene(70.0%detection rate),and 60 strains simultaneously were detected both erm(B)and mef(A)genes(64.5%detection rate).There were significant differences in the carriage of antibiotic resistance genes among GBS serotypes,with serotypesⅢI and I a exhibiting higher rates of erythromycin resistance.Genotyping results revealed that ST17 GBS demonstrated an erythromycin resistance rate as high as 92.3%,with all isolates carrying the erm(B)gene and 85.7%additionally harboring the mef(A)gene.Conclusion:The resistance gene spectrum of GBS in infants and young children is complex and diverse,with primary resistance mechanisms including target site modification and efflux pump-mediated efflux.Among these,the erm(B)gene and mef(A)gene are the predominant resistance genes.Different GBS serotypes exhibit distinct patterns of resistance gene carriage,and specific serotypes show a strong association with particular resistance genes.
作者
魏影
郭妍
朱立强
李桂秋
蒋一雄
Wei Ying;Guo Yan;Zhu Liqiang(Heilongjiang Provincial Hospital,Harbin,Heilongjiang,150036,China)
出处
《黑龙江医学》
2025年第24期2951-2954,2958,共5页
Heilongjiang Medical Journal
关键词
婴幼儿
无乳链球菌
耐红霉素类药物
耐药基因谱
血清型
Infants and toddlers
Streptococcus lactobacillus
Erythromycin-resistant drugs
Drug resistance gene profile
Serotype
