分子特征,抗菌敏感性,临床侵袭性黄金葡萄球菌分离物的生物膜形成能力
Weiguo Wang1, Qiuxaing Zhong1, Ke Cheng1
1Department of Clinical Laboratory, The First Hospital of Nanchang, Nanchang, Jiangxi, People's Republic of China.
Infection and drug resistance
|December 25, 2023
概括
分子类型检测显示ST59和ST7在侵袭性感染中占主导地位的金黄色葡萄球菌克隆. ST7是一种流行的MSSA克隆,表现出显著的生物膜形成能力,突显了持续监测和感染控制战略的需要.
科学领域:
- 微生物学 微生物学
- 传染性疾病 传染性疾病
- 分子流行病学分子流行病学
背景情况:
- 黄金葡萄球菌是侵入性感染的重要原因之一.
- 了解S. aureus的分子特性对于有效的治疗和控制至关重要.
- 抗菌耐药性和生物膜形成是导致治疗失败的关键毒性因素.
研究的目的:
- 研究来自侵袭性感染的Staphylococcus aureus分离物的分子特性,抗微生物耐药性和生物膜形成能力.
- 识别主导分子类型及其与耐药性和生物膜生产的关联.
- 为了告知感染控制策略对入侵性S. aureus.
主要方法:
- 使用多位点序列类型 (MLST),spa类型和SCCmec类型对92个S. aureus分离物的分析.
- 通过磁盘扩散和阿加稀释进行抗生素敏感性测试.
- 使用晶体紫色试验评估生物膜形成,并通过PCR和RT-qPCR检查生物膜相关基因表达 (icaA).
主要成果:
- ST59在甲素耐药黄金色杆菌 (MRSA) 中占主导地位 (43.6%),而ST7在甲素敏感黄金色杆菌 (MSSA) 中最常见 (39.0%).
- MRSA分离体显示出比MSSA更高的抗生素耐药率.
- 88.5%的分离物形成生物膜;MSSA分离物表现出比MRSA更高的生物膜形成能力 (P < 0.01),ST7分离物与其他序列类型相比显示出更大的生物膜形成和更高的icaA表达.
结论:
- 侵袭性S. aureus分离物表现出显著的分子异质性,ST59和ST7是主要的克隆.
- 由于ST7的流行率越来越高,其强大的生物膜形成能力令人担忧.
- 对于指导感染控制策略,不断监测新出现的黄金色杆菌系是必不可少的.
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