Tao Guixiang, Tan Hua, Chen Qian
Institute of Pediatrics, Children's Hospital of Nanjing Medical University, Nanjing, People's Republic of China.
Department of Clinical Laboratory, Children's Hospital of Nanjing Medical University, Nanjing, People's Republic of China.
Infect Drug Resist. 2023 May 24;16:3245-3255. doi: 10.2147/IDR.S412678. eCollection 2023.
The aim of this study was to analyze the genetic characteristics of three Enterobacteriaceae strains (one strain of and two strains of ) that produce both the NDM-5 and OXA-181 carbapenemases in pediatric patients.
Carbapenem-resistant Enterobacteriaceae (CRE) strains were collected from the Children's Hospital Affiliated to Nanjing Medical University in 2022. Resistance genes were detected by PCR. CRE strains that produced both the and genes were further characterized by antimicrobial susceptibility testing, multilocus sequence typing (MLST), plasmid conjugation assay, S1 nuclease-PFGE, Southern blotting and whole-genome sequencing.
Three Enterobacteriaceae strains carrying both the and resistance genes were screened. MLST results showed that the strain of carrying both and was ST410; the two strains of with both and were ST2601 and ST759. Conjugation assays showed that the plasmids harboring the and genes were self-transmissible. S1-PFGE and Southern blotting showed that the and genes were located on the plasmid with the size of about 60kb~. The genotyping results showed that the plasmid types were ColKP3 and IncX3.
This is the first report of Enterobacteriaceae strains that produce both NDM-5 and OXA-181 isolated from pediatric patients in China. Active infection control measures are urgently needed to prevent the spread of bacteria in children.
本研究旨在分析三株肠杆菌科菌株（一株肺炎克雷伯菌和两株大肠埃希菌）的遗传特征，这些菌株来自儿科患者，同时产生NDM-5和OXA-181碳青霉烯酶。
2022年从南京医科大学附属儿童医院收集耐碳青霉烯肠杆菌科（CRE）菌株。通过PCR检测耐药基因。对同时产生NDM-5和OXA-181基因的CRE菌株进一步进行药敏试验、多位点序列分型（MLST）、质粒接合试验、S1核酸酶-PFGE、Southern印迹和全基因组测序。
筛选出三株同时携带NDM-5和OXA-181耐药基因的肠杆菌科菌株。MLST结果显示，同时携带NDM-5和OXA-181的肺炎克雷伯菌菌株为ST410；同时携带NDM-5和OXA-181的两株大肠埃希菌菌株为ST2601和ST759。接合试验表明，携带NDM-5和OXA-181基因的质粒是自我传递的。S1-PFGE和Southern印迹显示，NDM-5和OXA-181基因位于大小约为60kb的质粒上。基因分型结果显示质粒类型为ColKP3和IncX3。
这是中国首次报道从儿科患者中分离出同时产生NDM-5和OXA-181的肠杆菌科菌株。迫切需要采取积极的感染控制措施以防止细菌在儿童中传播。
