Molecular Plant Taxonomy and Bioinformatics Research Laboratory, Department of Life Sciences, Dibrugarh University, Dibrugarh, Assam, 786004, India.
Integrated Molecular Diagnostic and Research Laboratory (BSL-2), District Hospital Tuensang, Tuensang, Nagaland, 798612, India.
World J Microbiol Biotechnol. 2024 Apr 17;40(6):167. doi: 10.1007/s11274-024-03977-1.
Carbapenem-resistant Acinetobacter baumannii poses a significant threat to public health globally, especially due to its ability to produce multiple carbapenemases, leading to treatment challenges. This study aimed to investigate the antibiotic resistance pattern of carbapenem-resistant A. baumannii isolates collected from different clinical settings in North East India, focusing on their genotypic and phenotypic resistance profiles. A total of 172 multidrug-resistant A. baumannii isolates were collected and subjected to antibiotic susceptibility test using the Kirby-Bauer disk diffusion method. Various phenotypic tests were performed to detect extended-spectrum β-lactamase (ESBL), metallo-β-lactamase (MBL), class C AmpC β-lactamase (AmpC), and carbapenem hydrolyzing class D β-lactamase (CHDL) production among the isolates. Overexpression of carbapenemase and cephalosporinase genes was detected among the isolates through both phenotypic and genotypic investigation. The antibiotic resistance profile of the isolates revealed that all were multidrug-resistant; 25% were extensively drug-resistant, 9.30% were pan-drug-resistant, whereas 91.27% were resistant to carbapenems. In the genotypic investigation, 80.81% of isolates were reported harbouring at least one metallo-β-lactamase encoding gene, with bla being the most prevalent at 70.34%, followed by bla at 51.16% of isolates. Regarding class D carbapenemases, bla and bla genes were detected in all the tested isolates, while bla bla and bla were found in 15.11%, 6.97%, and 1.74% isolates respectively. Further analysis showed that 31.97% of isolates co-harboured ESBL, MBL, AmpC, and CHDL genes, while 31.39% of isolates co-harboured ESBL, MBL, and CHDL genes with or without ISAba1 leading to extensively drug-resistant or pan drug-resistant phenotypes. This study highlights the complex genetic profile and antimicrobial-resistant pattern of the isolates circulating in North East India, emphasizing the urgent need for effective infection control measures and the development of alternative treatment strategies to combat these challenging pathogens.
耐碳青霉烯鲍曼不动杆菌对全球公共健康构成重大威胁，尤其是由于其能够产生多种碳青霉烯酶，导致治疗挑战。本研究旨在调查从印度东北部不同临床环境中分离的耐碳青霉烯鲍曼不动杆菌的抗生素耐药模式，重点关注其基因型和表型耐药谱。共收集了 172 株多药耐药鲍曼不动杆菌分离株，并使用 Kirby-Bauer 纸片扩散法进行抗生素敏感性试验。对分离株进行了各种表型试验，以检测超广谱β-内酰胺酶（ESBL）、金属β-内酰胺酶（MBL）、C 类 AmpC β-内酰胺酶（AmpC）和碳青霉烯水解类 Dβ-内酰胺酶（CHDL）的产生。通过表型和基因型研究检测到分离株中碳青霉烯酶和头孢菌素酶基因的过度表达。分离株的抗生素耐药谱显示，所有分离株均为多药耐药；25%为广泛耐药，9.30%为泛耐药，而 91.27%对碳青霉烯类耐药。在基因型研究中，80.81%的分离株报告至少携带一种金属β-内酰胺酶编码基因，其中 bla 最为常见，占 70.34%，其次是 bla，占 51.16%的分离株。关于 D 类碳青霉烯酶，所有测试的分离株均检测到 bla 和 bla 基因，而 bla bla 和 bla 分别在 15.11%、6.97%和 1.74%的分离株中发现。进一步分析表明，31.97%的分离株同时携带 ESBL、MBL、AmpC 和 CHDL 基因，而 31.39%的分离株同时携带 ESBL、MBL 和 CHDL 基因，或同时携带或不携带 ISAba1，导致广泛耐药或泛耐药表型。本研究强调了印度东北部流行的分离株的复杂遗传特征和抗微生物耐药模式，强调需要采取有效的感染控制措施和开发替代治疗策略来应对这些具有挑战性的病原体。
