在患者内,四种不同细菌物种之间的blaNDM-7等离子体的水平基因转移动态
O van Katwijk1, M Mulder2, L van Alphen2
1Department of Medical Microbiology, Infectious Diseases and Infection Prevention, Maastricht University Medical Centre, Maastricht, the Netherlands. Oscar.katwijk@mumc.nl.
概括
一名患者成为产生NDM的Citrobacter freundii的携带者,后来发展出,并获得了另外三种耐卡巴胺物种. 移动遗传元素促进了患者内的抗性基因转移.
科学领域:
- 医学微生物学 医学微生物学
- 传染性疾病 传染性疾病
- 抗微生物耐药性 抗微生物耐药性
背景情况:
- 碳酶产生的肠道细菌 (CPE) 构成了严重的全球健康威胁.
- blaNDM基因是一种常见的碳烯酶,通常位于移动遗传元素上.
- 横向基因转移 (HGT) 在抗菌素耐药性的传播中起着至关重要的作用.
研究的目的:
- 报告一个病例,患者感染了生产blaNDM的Citrobacter freundii.
- 为了研究同一个病人身上出现额外的碳烯酶产生物种.
- 探索移动遗传元素在单个宿主内抗菌素耐药性传播中的作用.
主要方法:
- 病例报告详细说明了临床过程和微生物学发现.
- 细菌物种的识别和抗微生物敏感性测试.
- 分子分析以表征碳烯酶基因和质粒,包括incX3质粒分析.
- 对横向基因转移事件的评估.
主要成果:
- 一名73岁的男性被确定为blaNDM产生Citrobacter freundii的携带者.
- 患者出现了腹部,并接受了皮佩拉西林-塔扎巴克坦治疗.
- 在随后的几个月里,发现了另外三种碳酶阳性物种 (Klebsiella oxytoca,Raoultella planticola,Serratia marscescens).
- 所有已识别的物种都在incX3等离子体上携带了blaNDM-7基因,这表明患者内的HGT.
结论:
- 这一案例凸显了在单个患者中获得抗菌素耐药性的动态性质.
- 移动遗传元素,特别是携带blaNDM-7的incX3等离子体,促进了不同细菌物种之间的耐药性传播.
- 有效的感染控制策略必须考虑移动遗传元素在传播抗菌素耐药性的作用.
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