Papa-Ezdra Romina, Cordeiro Nicolás F, Outeda Matilde, Garcia-Fulgueiras Virginia, Araújo Lucía, Seija Verónica, Ayala Juan A, Bado Inés, Vignoli Rafael
Departamento de Bacteriología y Virología, Instituto de Higiene, Facultad de Medicina, Av. Alfredo Navarro 3051, Montevideo 11600, Uruguay.
Departamento de Laboratorio Clínico, Área Microbiología, Hospital de Clínicas, Facultad de Medicina, Universidad de la República, Av. Italia s/n, Montevideo 11600, Uruguay.
Antibiotics (Basel). 2023 Feb 2;12(2):304. doi: 10.3390/antibiotics12020304.
Antibiotic resistance is an alarming problem throughout the world and carbapenem-resistant has been cataloged as critical in the World Health Organization list of microorganisms in urgent need for the development of new antimicrobials. In this work, we describe two novel resistance regions responsible for conferring a multidrug resistance phenotype to two clinical isolates of (Pa873 and Pa6415) obtained from patients hospitalized in the ICU of University Hospital of Uruguay. Bacterial identification and antibiotic susceptibility tests were performed using MALDI-TOF and the Vitek 2 system, respectively. WGS was performed for both isolates using Oxford Nanopore Technologies and Illumina and processed by means of hybrid assembly. Both isolates were resistant to ceftazidime, cefepime, piperacillin-tazobactam, aztreonam, and imipenem. Strain Pa6415 also showed resistance to ciprofloxacin. Both strains displayed MICs below the susceptibility breakpoint for CAZ-AVI plus 4 mg/L of aztreonam as well as cefiderocol. Both resistance regions are flanked by the left and right inverted repeats of IS in two small regions spanning 39.3 and 35.6 kb, for Pa6415 and Pa873, respectively. The resistance region of Pa6415 includes Tn, and the new Tn consists of IRi, In899, -IS, -IS--, -like, IS-like , IS, and IRR. On the other hand, the resistance region of Pa873 includes Tn and the new Tn (IRi, In899, , IS--, -like, IS-like , IS, and IRR). It is necessary to monitor the emergence of genetic structures that threaten to invalidate the available therapeutic resources.
抗生素耐药性是一个全球性的严重问题，耐碳青霉烯类细菌已被列入世界卫生组织急需开发新型抗菌药物的微生物名单。在本研究中，我们描述了两个新的耐药区域，它们赋予了从乌拉圭大学医院重症监护病房住院患者中分离出的两种临床菌株（Pa873和Pa6415）多重耐药表型。分别使用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF）和Vitek 2系统进行细菌鉴定和抗生素敏感性试验。使用牛津纳米孔技术公司和Illumina公司的技术对这两种菌株进行全基因组测序（WGS），并通过混合组装进行处理。两种菌株均对头孢他啶、头孢吡肟、哌拉西林-他唑巴坦、氨曲南和亚胺培南耐药。菌株Pa6415还对环丙沙星耐药。两种菌株对头孢他啶-阿维巴坦加4mg/L氨曲南以及头孢地尔的最低抑菌浓度（MIC）均低于敏感阈值。两个耐药区域分别位于39.3kb和35.6kb的两个小区域内，两侧分别为插入序列（IS）的左右反向重复序列，分别对应Pa6415和Pa873。Pa6415的耐药区域包括转座子Tn，新的转座子由IRi、In899、-IS、-IS--、-like、IS-like、IS和IRR组成。另一方面，Pa873的耐药区域包括转座子Tn和新的转座子（IRi、In899、、IS--、-like、IS-like、IS和IRR）。有必要监测那些可能使现有治疗资源失效的遗传结构的出现。
