Escherichia coli Sequence Type ST131 as the Major Cause of Serious Multidrug-Resistant E. coli Infections in the United States
Escherichia coli Sequence Type ST131 as the Major Cause of Serious Multidrug-Resistant E. coli Infections in the United States
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DOI：
10.1086/653932
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发表时间：
2010-08-01
影响因子：
11.8
通讯作者：
Castanheira, Mariana
中科院分区：
文献类型：
--
作者：
Johnson, James R.;Johnston, Brian;Castanheira, Mariana
背景。大肠杆菌序列类型 ST131 (O25:H4) 与 CTX-M-15 超广谱 β-内酰胺酶相关，已在国际上作为多重耐药病原体出现，但在美国却很少受到关注。方法。根据 SENTRY 和美罗培南年度药敏试验信息收集 (MYSTIC) 监测计划，2007 年从美国各地住院患者中分离出 127 株大肠杆菌临床分离株，按广谱头孢菌素和氟喹诺酮表型以及 bla(CTX-M-15) 基因型进行分层，评估了系统发育组、ST131 状态、敏感性概况、毒力基因型、gyrA 和 parC 序列以及脉冲场凝胶电泳图谱。结果。 54 个已鉴定的 ST131 分离株（全部对氟喹诺酮耐药）估计占来源群体的 17%，其中对广谱头孢菌素或氟喹诺酮类耐药的分离株占 67%-69%，对氟喹诺酮类和甲氧苄啶-磺胺甲恶唑均耐药的分离株占 55%，以及多重耐药分离株的 52%。与其他耐药分离株相比，它们独特的毒力分布更广泛，但与抗菌素敏感分离株相比也同样广泛。脉冲场分析表明，bla(CTX-M-15) 在特定 ST131 谱系中集中，在不同地点之间持续传播。历史 ST131 分离株在 gyrA 和 parC 中缺乏 2007 ST131 分离株保守的氟喹诺酮耐药相关单核苷酸多态性。结论。单一大肠杆菌克隆群 ST131 可能在 2007 年引起了美国最显着的抗菌药物耐药性大肠杆菌感染，从而构成了新的重要公共卫生威胁。与其他大肠杆菌相比，其毒力和/或抗菌素耐药性增强，加上在不同地区的持续传播，可能是 ST131 成功的基础。需要紧急调查 ST131 的来源和传播途径，以便为缓解工作提供信息。
Background. Escherichia coli sequence type ST131 (O25:H4), associated with the CTX-M-15 extended-spectrum beta-lactamase, has emerged internationally as a multidrug-resistant pathogen but has received little attention in the United States.Methods. From the SENTRY and Meropenem Yearly Susceptibility Test Information Collection (MYSTIC) surveillance programs, 127 E. coli clinical isolates from hospitalized patients across the United States in 2007, stratified by extended-spectrum cephalosporin and fluoroquinolone phenotype and bla(CTX-M-15) genotype, were assessed for phylogenetic group, ST131 status, susceptibility profile, virulence genotype, gyrA and parC sequence, and pulsed-field gel electrophoresis profile.Results. The 54 identified ST131 isolates (all fluoroquinolone resistant) accounted for an estimated 17% of the source populations, including 67%-69% of isolates resistant to extended-spectrum cephalosporins or fluoroquinolones, 55% of those resistant to both fluoroquinolones and trimethoprim-sulfamethoxazole, and 52% of multidrug-resistant isolates. Their distinctive virulence profiles were more extensive compared with other antimicrobial-resistant isolates but similarly extensive compared with antimicrobial-susceptible isolates. Pulsed-field profiling suggested ongoing dissemination among locales, with concentration of bla(CTX-M-15) within specific ST131 lineages. A historical ST131 isolate lacked the 2007 ST131 isolates' conserved fluoroquinolone resistance-associated single-nucleotide polymorphisms in gyrA and parC.Conclusions. A single E. coli clonal group, ST131, probably caused the most significantly antimicrobial-resistant E. coli infections in the United States in 2007, thereby constituting an important new public health threat. Enhanced virulence and/or antimicrobial resistance compared with other E. coli, plus ongoing dissemination among locales, may underlie ST131's success. Urgent investigation of the sources and transmission pathways of ST131 is needed to inform mitigation efforts.