Department of Anesthesiology, School of Medicine, Kyoto, Japan.
Division of Infection Control & Laboratory Medicine, University Hospital, Kyoto Prefectural University of Medicine, Kyoto, Japan.
J Infect Chemother. 2020 Mar;26(3):257-265. doi: 10.1016/j.jiac.2019.09.014. Epub 2019 Oct 31.
The secondary in-hospital epidemiological investigation for drug-resistant Pseudomonas aeruginosa infections was conducted to evaluate the in-hospital situation and identify any associations between exoenzyme genotypes and other genotypes and antimicrobial resistance characteristics, at the University Hospital in Kyoto, Japan, following a reported outbreak of antimicrobial-resistant P. aeruginosa ST357 between 2005 and 2014. Twelve of the 546 P. aeruginosa isolates collected during the follow-up period were resistant to more than two classes of antimicrobials. All isolates were resistant to fluoroquinolones and 8 (66.7%) showed carbapenem resistance. None of the isolates fulfilled the clinical criteria for multidrug-resistant P. aeruginosa. All isolates were metallo-β-lactamase test-negative. Among five exoS (-)exoU (+) isolates, three possessing a class 1 integron with gene cassette aadB + cmlA6 were classified as ST357, and one isolate containing a class 1 integron with aacA31 was ST235. Collectively, the second survey results confirm that the initial outbreak is currently undergoing convergence. By combining data from the first and second surveys, we showed that prevalent STs such as ST357 and ST235 are associated with fluoroquinolone resistance, class 1 integron-associated resistance to β-lactams and aminoglycosides, and cytotoxic exoU (+) genotypes. With the current worldwide spread of ST357 and ST235 isolates, it is important to evaluate epidemiological trends for high-risk P. aeruginosa isolates by continuous hospital monitoring.
日本京都大学医院对 2005 年至 2014 年期间报告的耐碳青霉烯铜绿假单胞菌 ST357 暴发事件进行了院内耐药铜绿假单胞菌的二次院内流行病学调查，以评估院内情况，并确定外毒素基因型与其他基因型和抗菌药物耐药特征之间的相关性。在随访期间采集的 546 株铜绿假单胞菌分离株中，有 12 株对超过 2 类抗菌药物耐药。所有分离株均对氟喹诺酮类药物耐药，8 株（66.7%）显示出碳青霉烯类耐药。没有分离株符合多重耐药铜绿假单胞菌的临床标准。所有分离株均为金属β-内酰胺酶试验阴性。在 5 株 exoS（-）exoU（+）分离株中，有 3 株携带带有 aadB+cmlA6 基因盒的 1 类整合子，被归类为 ST357，1 株携带 aacA31 的 1 类整合子被归类为 ST235。第二次调查结果证实，最初的暴发正在收敛。通过结合第一次和第二次调查的数据，我们表明流行的 ST 如 ST357 和 ST235 与氟喹诺酮耐药、1 类整合子相关的β-内酰胺和氨基糖苷类耐药以及细胞毒性 exoU（+）基因型有关。鉴于目前全球 ST357 和 ST235 分离株的传播，通过持续的医院监测评估高危铜绿假单胞菌分离株的流行病学趋势非常重要。
