Salem Salma, Osama Dina, Abdelsalam Nehal Adel, Shata Ahmed H, Mouftah Shaimaa F, Elhadidy Mohamed
Center for Genomics, Helmy Institute for Medical Sciences, Zewail City of Science and Technology, Giza, Egypt.
Biomedical Sciences Program, University of Science and Technology, Zewail City of Science and Technology, Giza, Egypt.
BMC Infect Dis. 2025 Jun 11;25(1):803. doi: 10.1186/s12879-025-11185-x.
Acinetobacter baumannii (A. baumannii) has emerged as a major public health threat in low- and middle-income countries (LMICs), particularly in Egypt, due to its remarkable ability to acquire and transfer resistance genes, as highlighted in the WHO bacterial Priority Pathogens List 2024 classification. This pilot study aimed to characterize 18 A. baumannii isolates from Egyptian healthcare settings, focusing on clonal lineages, antibiotic resistance determinants, horizontal gene transfer potential, and the presence of virulence factors and chromosomal mutations.
Antimicrobial susceptibility testing was performed to determine resistance profiles using minimum inhibitory concentrations. Whole-genome sequencing was used to identify β-lactamase, carbapenemase, and other antibiotic resistance genes (ARGs), as well as mobile genetic elements (MGEs). Clonal relationships among isolates were assessed via core genome multilocus sequence typing (cgMLST).
Phenotypic analysis revealed that 72% of the isolates were extensively drug-resistant (XDR), exhibiting resistance to all tested antibiotics except colistin. Clonal diversity analysis identified 11 Oxford sequence types (STs), including two novel STs (ST3309 and ST3321), and six international clonal (IC) groups, with IC2 being the most prevalent. Additionally, eight Pasteur STs were detected, with ST570 being the most frequent. The cgMLST analysis showed that two Egyptian ST570 isolates clustered with a strain from Saudi Arabia, suggesting potential regional transmission. Genomic analysis revealed the widespread dissemination of ARGs via MGEs, particularly rep plasmids and insertion sequence elements, which contributed significantly to genomic diversity and antibiotic resistance.
This pilot study highlights the clonal diversity of A. baumannii in Egypt and underscores the critical role of MGEs in the spread of resistance genes. Targeted genomic surveillance and infection control are essential to curb the spread of high-risk resistant A. baumannii clones in Egyptian clinical settings.
鲍曼不动杆菌已成为低收入和中等收入国家（LMICs），尤其是埃及的主要公共卫生威胁，因为它具有获取和转移耐药基因的显著能力，这在世界卫生组织2024年细菌重点病原体列表分类中得到了强调。这项初步研究旨在对从埃及医疗机构分离出的18株鲍曼不动杆菌进行特征分析，重点关注克隆谱系、抗生素耐药决定因素、水平基因转移潜力以及毒力因子和染色体突变的存在情况。
采用最低抑菌浓度进行抗菌药物敏感性测试以确定耐药谱。全基因组测序用于鉴定β-内酰胺酶、碳青霉烯酶和其他抗生素耐药基因（ARGs）以及移动遗传元件（MGEs）。通过核心基因组多位点序列分型（cgMLST）评估分离株之间的克隆关系。
表型分析显示，72%的分离株为广泛耐药（XDR），除黏菌素外，对所有测试抗生素均耐药。克隆多样性分析确定了11种牛津序列类型（STs），包括两种新的STs（ST3309和ST3321），以及六个国际克隆（IC）组，其中IC2最为普遍。此外，检测到八个巴斯德STs，其中ST570最为常见。cgMLST分析表明，两株埃及ST570分离株与一株来自沙特阿拉伯的菌株聚类，表明可能存在区域传播。基因组分析揭示了ARGs通过MGEs广泛传播，特别是复制质粒和插入序列元件，这对基因组多样性和抗生素耐药性有显著贡献。
这项初步研究突出了埃及鲍曼不动杆菌的克隆多样性，并强调了MGEs在耐药基因传播中的关键作用。有针对性的基因组监测和感染控制对于遏制埃及临床环境中高危耐药鲍曼不动杆菌克隆的传播至关重要。
