Department of Clinical Laboratory, Xiangya Hospital, Central South University, Changsha, Hunan, China.
Department of Clinical Laboratory, Xiangya Hospital, Central South University, Changsha, Hunan, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Changsha, Hunan, China.
J Glob Antimicrob Resist. 2024 Sep;38:116-122. doi: 10.1016/j.jgar.2024.05.002. Epub 2024 May 11.
To investigate the clinical and molecular epidemiological characteristics of bla-carrying Klebsiella pneumoniae in a tertiary hospital in China.
Ten carbapenem-resistant K. pneumoniae (CRKP) isolates carrying the bla gene were collected. Molecular characteristics were analysed using whole-genome sequencing. Plasmid conjugation experiments were used to analyse conjugation of the plasmids. We compared and analysed K. pneumoniae-carrying bla genomic datasets obtained from the National Center for Biotechnology Information (NCBI) with the strains in this study.
All 10 CRKP isolates carrying bla were collected from 10 adult patients in the respiratory intensive care unit. These strains were only sensitive to polymyxins and tigecycline due to them simultaneously carrying multiple resistance genes, namely bla, fosA, oqxA, and oqxB. Notably, R29 harboured two carbapenemase genes (bla and bla). These strains had similar drug-resistant phenotypes and genes, all belonging to sequence type (ST)196. Additionally, the patients had experienced spatiotemporal intersection during hospitalization, suggesting that these strains underwent clonal transmission, but they belonged to different clonal clusters from the bla-positive K. pneumoniae currently published in the NCBI. Among the 10 strains, bla was located on the IncN plasmid, and six strains had successfully transferred the plasmid to the recipient strain EC600 through plasmid conjugation.
The bla-positive ST196 CRKP isolate showed clonal distribution in the respiratory intensive care unit, which was mediated by the IncN plasmid. Consequently, there should be increased monitoring of carbapenem-resistant strains in clinical settings to prevent and control its transmission.
研究中国一家三级医院携带 bla 基因的肺炎克雷伯菌的临床和分子流行病学特征。
收集了 10 株携带 bla 基因的耐碳青霉烯肺炎克雷伯菌（CRKP）分离株。采用全基因组测序分析分子特征。通过质粒接合实验分析质粒的接合。我们将从美国国立生物技术信息中心（NCBI）获得的与本研究中菌株携带 bla 基因组数据集进行比较和分析。
从呼吸重症监护病房的 10 位成年患者中收集到 10 株携带 bla 的 CRKP 分离株。由于这些菌株同时携带多种耐药基因，如 bla、fosA、oqxA 和 oqxB，它们仅对多黏菌素和替加环素敏感。值得注意的是，R29 携带两种碳青霉烯酶基因（bla 和 bla）。这些菌株具有相似的耐药表型和基因，均属于序列型（ST）196。此外，患者在住院期间存在时空交叉，表明这些菌株发生了克隆传播，但它们属于与目前在 NCBI 中发表的 bla 阳性肺炎克雷伯菌不同的克隆簇。在 10 株菌株中，bla 位于 IncN 质粒上，6 株菌株通过质粒接合成功将质粒转移到受体菌株 EC600 中。
bla 阳性 ST196 CRKP 分离株在呼吸重症监护病房呈克隆分布，由 IncN 质粒介导。因此，应增加对临床碳青霉烯耐药菌株的监测，以预防和控制其传播。
