Istituto Superiore di Sanità, Rome, Italy.
J Antimicrob Chemother. 2013 Nov;68(11):2482-6. doi: 10.1093/jac/dkt235. Epub 2013 Jun 25.
We report the case of a kidney-transplant patient, suffering an intra-abdominal abscess at the surgical site caused by a carbapenem-resistant ST258 Klebsiella pneumoniae clone, producing the KPC-3 carbapenemase. Under tigecycline treatment, the patient developed a sepsis caused by a carbapenem-susceptible ST258 K. pneumoniae strain. Complete DNA sequences of the plasmids carried by the resistant and susceptible strains from this patient were determined.
The complete DNA sequences of plasmids were obtained by applying the 454 Genome Sequencer FLX-PLUS procedure on a library constructed of total plasmid DNA purified from the carbapenem-resistant and -susceptible strains.
In the carbapenem-resistant strain, four plasmids encoding 24 resistance genes, including blaKPC-3, and two putative virulence clusters were detected. In the susceptible strain, large rearrangements occurred in the KPC-carrying plasmid, causing the deletion of the entire Tn4401::blaKPC-3 transposon, with the consequent reversion of the strain to carbapenem susceptibility. The patient was successfully treated with carbapenems and fully recovered.
The description of the plasmid content in these two strains gives interesting insights into the plasticity of KPC-carrying plasmids in K. pneumoniae.
我们报告了一例肾移植患者的病例，该患者在手术部位发生腹腔脓肿，由产 KPC-3 碳青霉烯酶的耐碳青霉烯 ST258 肺炎克雷伯菌克隆引起。在替加环素治疗下，该患者发生了由耐碳青霉烯 ST258 肺炎克雷伯菌引起的败血症。我们确定了该患者携带的耐药和敏感菌株的质粒的完整 DNA 序列。
采用 454 基因组测序仪 FLX-PLUS 程序，对从耐碳青霉烯和碳青霉烯敏感菌株中提取的总质粒 DNA 构建的文库进行全质粒 DNA 测序。
在耐碳青霉烯菌株中，检测到四个编码 24 种耐药基因的质粒，包括 blaKPC-3 和两个推定的毒力簇。在敏感菌株中，携带 KPC 的质粒发生了较大的重排，导致整个 Tn4401::blaKPC-3 转座子缺失，使菌株对碳青霉烯的敏感性恢复。患者经碳青霉烯类药物治疗后成功治愈并完全康复。
这两个菌株的质粒内容描述为我们提供了关于肺炎克雷伯菌中携带 KPC 的质粒的可变性的有趣见解。
