Liu Lili, Huang Yuan, Wang Yaping, Jiang Yunlan, Liu Kang, Pei Zhongxia, Li Zhiping, Zhu Yuqiong, Liu Dan, Li Xiaoyue
Department of Nosocomial Infection, Anqing First People's Hospital of Anhui Medical University, Anqing City, Anhui Province, People's Republic of China.
Department of Science and Education, Anqing Municipal Hospital, Anqing City, Anhui Province, People's Republic of China.
Infect Drug Resist. 2024 Dec 31;17:5925-5945. doi: 10.2147/IDR.S491858. eCollection 2024.
To evaluate the clinical characteristics, antimicrobial resistance (AMR) phenotypes and genotypes, and homology features of carbapenem-resistant (CRAB) in intensive care unit (ICU) and to provide basis for effectively prevention, control and treatment of nosocomial infections caused by CRAB.
A total of 39 CRAB strains isolated from hospitalized patients in the ICU and neurosurgical ICU (NICU) between 2020 and 2023 were subjected to antimicrobial susceptibility testing and whole-genome sequencing (WGS). Virulence factor genes (VFGs), antimicrobial resistance genes (ARGs), multilocus sequencing typing (MLST), complete genome multilocus sequencing typing (cgMLST), average nucleotide identity (ANI), and single nucleotide polymorphism (SNP) analyses were performed using WGS.
All CRAB strains were 100% resistant to ciprofloxacin, ceftazidime, piperacillin/tazobactam, and ticarcillin/clavulanic acid. A total of 48 antimicrobial resistance genes (ARGs) were found in the 39 CRAB strains, including OXA-66, OXA-23, ADC-30, ADC-73, which confered resistance to carbapenems, cephalosporins, fluoroquinolones, aminoglycosides, tetracycline and sulfonamides. There were 128 VFGs, including genes encoding the AdeFGH efflux pump, lipopolysaccharide (LpsBLC), outer membrane protein A (OmpA), penicillin-binding protein (PbpG), biofilm-associated proteins (bap, pgaBCD, CsuABCDE), type VI secretion system protein (Tss), quorum sensing protein (AbaI/AbaR). Six clonal lineages were identified by Oxford MLST method, whereas one sequence type (ST2) was identified using the Pasteur MLST method. ANI analysis, heat map of SNP analysis, and phylogenetic tree based on core SNP revealed six clusters, and the strain classification results were consistent with these different methods. Ten clonal lineages were identified by cgMLST.
The CRAB strains were ST2 clones accompanied by severe resistance to commonly used antibiotics and abundant ARGs and VFGs in genotype. Strict measures should be implemented to prevent and control transmissions and infections. CgMLST and SNPs analyses showed excellent discriminatory power in homology analysis.
评估重症监护病房（ICU）中耐碳青霉烯类鲍曼不动杆菌（CRAB）的临床特征、抗菌药物耐药（AMR）表型和基因型以及同源性特征，为有效预防、控制和治疗CRAB引起的医院感染提供依据。
对2020年至2023年间从ICU和神经外科重症监护病房（NICU）住院患者中分离出的39株CRAB菌株进行抗菌药物敏感性试验和全基因组测序（WGS）。使用WGS进行毒力因子基因（VFGs）、抗菌药物耐药基因（ARGs）、多位点测序分型（MLST）、全基因组多位点测序分型（cgMLST）、平均核苷酸同一性（ANI）和单核苷酸多态性（SNP）分析。
所有CRAB菌株对环丙沙星、头孢他啶、哌拉西林/他唑巴坦和替卡西林/克拉维酸的耐药率均为100%。在39株CRAB菌株中总共发现了48个抗菌药物耐药基因（ARGs），包括赋予对碳青霉烯类、头孢菌素类、氟喹诺酮类、氨基糖苷类、四环素类和磺胺类耐药的OXA-66、OXA-23、ADC-30、ADC-73。有128个VFGs，包括编码AdeFGH外排泵、脂多糖（LpsBLC）、外膜蛋白A（OmpA）、青霉素结合蛋白（PbpG）、生物膜相关蛋白（bap、pgaBCD、CsuABCDE）、VI型分泌系统蛋白（Tss）、群体感应蛋白（AbaI/AbaR）的基因。通过牛津MLST方法鉴定出6个克隆谱系，而使用巴斯德MLST方法鉴定出1个序列类型（ST2）。ANI分析、SNP分析热图以及基于核心SNP的系统发育树显示出6个簇，菌株分类结果与这些不同方法一致。通过cgMLST鉴定出10个克隆谱系。
CRAB菌株为ST2克隆，伴有对常用抗生素的严重耐药性以及基因型中丰富的ARGs和VFGs。应实施严格措施以预防和控制传播及感染。CgMLST和SNP分析在同源性分析中显示出出色的鉴别能力。
