Department of Medical Laboratory Science and Biotechnology, College of Health Sciences, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan.
Department of Medical Laboratory Science and Biotechnology, College of Health Sciences, Kaohsiung Medical University, Kaohsiung, Taiwan.
J Microbiol Immunol Infect. 2017 Oct;50(5):653-661. doi: 10.1016/j.jmii.2017.03.003. Epub 2017 Jun 28.
Epidemiology of fosfomycin susceptibility and the plasmid-mediated fosfomycinase genes of carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates in Taiwan remain unclear.
642 CRKP clinical isolates were collected from a nation-wide surveillance study (16 hospitals) in Taiwan in 2012-2013. Antimicrobial susceptibilities were determined. PFGE and MLST determined the clonal relatedness. Carbapenemases and fosfomycinases genes were detected by PCR, and their flanking regions were determined by PCR and sequencing. Synergistic activity of meropenem with fosfomycin was examined by the checkerboard method.
In total, 36.4% (234/642) of CRKP isolates in Taiwan were resistant to fosfomycin. Among 234 fosfomycin-resistant CRKP isolates, PFGE analysis revealed 81 pulsotypes. Pulsotype XXIII (n = 63) was predominant and belonged to ST11. 71 had carbapnemases (65 bla-positive, 1 bla-positive and 5 bla-positive) and 62 had fosfomycinases (35 fosA3-positive and 27 foskp96-positive). Only 18.5% (5/27) of foskp96-positive isolates carried foskp96 and bla, while 71.4% (25/35) of fosA3-positive isolates contained fosA3 and bla. There were five types of flanking sequences for fosA3, and 85.7% (30/35) of fosA3 genes were flanked by IS26, suggesting possible horizontal gene transfer. Synergistic effect of fosfomycin and meropenem was observed in all 25 randomly selected pulsotype XXIII strains (100%; 25/25), even those containing fosfomycinase (48%, 12/25) or carbapnemase (96%, 24/25).
A clone (pulsotype XXIII, ST11) has been found to be prevailing among fosfomycin-resistant CRKP in Taiwan. According to the in vitro data, the combination of fosfomycin and meropenem is a potentially alternative choice.
台湾地区碳青霉烯类耐药肺炎克雷伯菌（CRKP）中磷霉素敏感性和质粒介导的磷霉素酶基因的流行病学情况尚不清楚。
2012-2013 年，从台湾地区一项全国性监测研究（16 家医院）中收集了 642 株 CRKP 临床分离株。测定抗菌药物敏感性。通过 PFGE 和 MLST 确定克隆相关性。采用 PCR 检测碳青霉烯酶和磷霉素酶基因，并通过 PCR 和测序检测其侧翼区。采用棋盘法检测美罗培南与磷霉素的协同活性。
在台湾地区，共有 36.4%（234/642）的 CRKP 分离株对磷霉素耐药。234 株磷霉素耐药 CRKP 分离株中，PFGE 分析显示 81 个脉冲场凝胶电泳型。XXIII 型（n=63）为优势型，属于 ST11。71 株携带碳青霉烯酶（65 株 bla 阳性，1 株 bla 阳性和 5 株 bla 阳性），62 株携带磷霉素酶（35 株 fosA3 阳性和 27 株 foskp96 阳性）。仅 18.5%（5/27）的 foskp96 阳性分离株携带 fosA3 和 bla，而 71.4%（25/35）的 fosA3 阳性分离株含有 fosA3 和 bla。fosA3 基因有 5 种侧翼序列类型，其中 85.7%（30/35）的 fosA3 基因侧翼有 IS26，提示可能存在水平基因转移。在 25 株随机选择的 XXIII 型脉冲场凝胶电泳型菌株中，均观察到磷霉素和美罗培南的协同作用（100%；25/25），即使菌株携带磷霉素酶（48%；12/25）或碳青霉烯酶（96%；24/25）。
在台湾地区，发现一种流行于磷霉素耐药 CRKP 的克隆（XXIII 型，ST11）。根据体外数据，磷霉素和美罗培南联合使用可能是一种替代选择。
