Gomez Sonia A, Sanz María Belén, Rapoport Melina, Sucin Graciela, Corallo Teresa A, Poklepovich Tomás, Campos Josefina, Ceriana Paola, de Mendieta Juan Manuel, Prieto Mónica, Pasteran Fernando, Corso Alejandra
Servicio Antimicrobianos, INEI-ANLIS "Dr. Carlos G. Malbrán", National and Regional Reference Laboratory in Antimicrobial Resistance (NRRLAR), Buenos Aires C1282AFF, Argentina.
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires C1425FQB, Argentina.
Pathogens. 2023 Jul 21;12(7):961. doi: 10.3390/pathogens12070961.
We aimed to describe a colistin (COL)-resistant (R) (Cvi) isolate from a septic patient in Argentina expressing a previously unknown gene, .
In 2019, a 12 year old child was injured with a thorn in a lagoon. The child was hospitalized due to sepsis and multiple abscesses. Cvi was isolated from skin and soft tissue and tracheal aspirate. The patient was successfully treated with imipenem (IMI) plus amikacin. Antimicrobial susceptibility was assessed by disk diffusion, broth microdilution, and the E-test. Carbapenemase activity was assayed by double-disk synergy and microbiological tests. Resistance, virulence, and additional gene searches were performed by in silico analysis of sequences obtained by whole-genome sequencing (WGS). A maximum likelihood phylogenetic tree was built with public Cvi genomes.
R was seen for IMI and COL. Expression of a metallo-β-lactamase was confirmed. Genome analysis revealed , a subclass B2 metallo-β-lactamase with 62.66% ID with CphA from (WP081086394). R to COL could be attributed to the and genes. Virulence factors required for invasion and toxicity were also found. No plasmids were detected. The phylogeny tree showed two main clades with geographical distinction, and the isolate studied here stands alone in a branch closely related to two clinical isolates from the USA.
This is the second report of infection by Cvi in Argentina. This pathogen carried a new gene, , a metallo-β-lactamase that can be detected by routine methods. Prompt suspicion of infection is crucial to treating this rare pathogen rapidly and properly.
我们旨在描述从阿根廷一名脓毒症患者中分离出的一株对黏菌素（COL）耐药（R）的阴沟肠杆菌（Cvi），该菌株表达一种此前未知的基因。
2019年，一名12岁儿童在泻湖被荆棘刺伤。该儿童因脓毒症和多处脓肿住院。从皮肤和软组织以及气管吸出物中分离出Cvi。患者接受亚胺培南（IMI）加阿米卡星治疗成功。通过纸片扩散法、肉汤微量稀释法和E-test评估抗菌药物敏感性。通过双纸片协同试验和微生物学试验检测碳青霉烯酶活性。通过对全基因组测序（WGS）获得的序列进行计算机分析，进行耐药性、毒力和其他基因搜索。用公开的Cvi基因组构建最大似然系统发育树。
观察到对IMI和COL耐药。证实了金属β-内酰胺酶的表达。基因组分析显示，这是一种B2亚类金属β-内酰胺酶，与来自肺炎克雷伯菌（WP081086394）的CphA有62.66%的同一性。对COL的耐药性可归因于 和 基因。还发现了侵袭和毒性所需的毒力因子。未检测到质粒。系统发育树显示有两个主要分支且有地域差异，此处研究的分离株独自位于与来自美国的两个临床分离株密切相关的一个分支中。
这是阿根廷第二例Cvi感染报告。该病原体携带一种新基因， ，一种可通过常规方法检测到的金属β-内酰胺酶。迅速怀疑Cvi感染对于快速且恰当地治疗这种罕见病原体至关重要。
