Álvarez Verónica E, Knecht Camila, Piekar María, García Allende Natalia, Gonzales Machuca Adrián, Campos Josefina, Carpio Eduardo, Páez Laura, Fox Bárbara, Fernández Canigia Liliana, Leguina Carolina, Quiroga María P, Centrón Daniela
Laboratorio de Investigaciones en Mecanismos de Resistencia a Antibióticos, Instituto de Investigaciones en Microbiología y Parasitología Médica, Facultad de Medicina, Universidad de Buenos Aires - Consejo Nacional de Investigaciones Científicas y Técnicas (IMPaM, UBA-CONICET), Paraguay 2155, Ciudad Autónoma de Buenos Aires, Argentina.
Clúster de Bioinformática, Facultad de Medicina, Universidad de Buenos Aires - Consejo Nacional de Investigaciones Científicas y Técnicas (IMPaM, UBA-CONICET), Paraguay 2155, CABA Ciudad Autónoma de Buenos Aires, Argentina.
Curr Microbiol. 2025 Aug 13;82(10):451. doi: 10.1007/s00284-025-04424-6.
Our aim was to investigate lineages and resistome of carbapenemase-producing Klebsiella oxytoca Complex (KoC) strains isolated from 2019 to 2022 from colonization and infection samples to evaluate their potential dissemination. This prospective study showed the presence of eight multidrug-resistant K. oxytoca ST2 strains harboring bla, bla, or bla genes among both colonized (n = 5) and infected (n = 3) patients isolated during this period. Genomic analysis revealed antimicrobial resistance genes, virulence loci, including kleboxymycin and yersiniabactin, highlighting their resistance and pathogenicity in clinical settings. CgSNP analysis revealed that five isolates, HA8pKo, HA10pKo, HA14pKo, HA21Ko and HA22pKo, were the same strain disseminating among colonized patients (n = 4) during two months in 2019. K. oxytoca HA8pKo, HA10pKo, HA14pKo, HA21Ko, and HA22pKo strains shared three replicon types (Col(pHAD28), IncM1, and IncFII (K) as well as the bla gene. The bla gene was contained in the IncFII (K) replicon (pDCVEA12-KPC) which harbored a mercury resistance (mer) gene locus. The silent dissemination of carbapenemase-producing KoC strains colonizing patients is a cause for concern, prompting questions about the most suitable approaches for asymptomatic patients to prevent the spread and potential outbreaks. Our findings reinforced the relevance of epidemiological surveillance programs to identify the reservoir of carbapenemase-producing strains.
我们的目的是调查2019年至2022年从定植和感染样本中分离出的产碳青霉烯酶的产酸克雷伯菌复合体（KoC）菌株的谱系和耐药组，以评估其潜在传播情况。这项前瞻性研究表明，在此期间分离出的定植患者（n = 5）和感染患者（n = 3）中均存在8株携带bla、bla或bla基因的多重耐药产酸克雷伯菌ST2菌株。基因组分析揭示了抗菌耐药基因、毒力位点，包括kleboxymycin和yersiniabactin，突出了它们在临床环境中的耐药性和致病性。CgSNP分析显示，5株分离株HA8pKo、HA10pKo、HA14pKo、HA21Ko和HA22pKo是同一菌株，于2019年在两个月内定植于患者（n = 4）中传播。产酸克雷伯菌HA8pKo、HA10pKo、HA14pKo、HA21Ko和HA22pKo菌株共有三种复制子类型（Col(pHAD28)、IncM1和IncFII (K)）以及bla基因。bla基因包含在IncFII (K)复制子（pDCVEA12-KPC）中，该复制子含有汞抗性（mer）基因位点。定植于患者的产碳青霉烯酶KoC菌株的隐匿性传播令人担忧，引发了关于无症状患者预防传播和潜在暴发的最合适方法的问题。我们的研究结果强化了流行病学监测计划对于识别产碳青霉烯酶菌株储存库的相关性。
