Matovina Mihaela, Abram Maja, Repac-Antić Davorka, Knežević Samira, Bubonja-Šonje Marina
PhD, Division of Organic Chemistry and Biochemistry, Rudjer Bošković Institute, Bijenička cesta 54, 10 000 Zagreb, Croatia.
MD, PhD, Department of Microbiology, Faculty of Medicine, University of Rijeka, Braće Branchetta 20, 51 000 Rijeka, Croatia and Department of Clinical Microbiology, Clinical Hospital Center Rijeka, Krešimirova 40, 51 000 Rijeka, Croatia.
Germs. 2021 Jun 2;11(2):199-210. doi: 10.18683/germs.2021.1257. eCollection 2021 Jun.
Carbapenem-resistant is an emerging healthcare-associated pathogen with dynamic molecular epidemiology. This study presents a retrospective analysis of the distribution and antibiotic resistance patterns of ertapenem-resistant ESBL-producing strains recovered during an outbreak from 2012 to 2014 in a Croatian University hospital.
We aimed to estimate genetic relatedness of clinical isolates and underlying mechanisms that conferred the ertapenem-resistant phenotype.
Expression analysis of genes involved in the antibiotic resistance showed reduced expression of major non-selective porin channel OmpK35. Reduced expression of OmpK36 porin channel in isolates resistant to at least one more carbapenem, apart from the ertapenem, was found to a lesser degree. Pulsed-field gel electrophoresis analysis of genomic DNA revealed that almost all isolates belonged to the same genetic clone.
Caution regarding ertapenem-resistant, carbapenemase-negative porin-deficient mutants of is required as they are widespread, and under selective pressure this could result in a local clonal outbreak.
耐碳青霉烯类肠杆菌科细菌是一种新出现的与医疗保健相关的病原体，其分子流行病学动态变化。本研究对2012年至2014年克罗地亚一家大学医院暴发期间分离出的产超广谱β-内酰胺酶（ESBL）且耐厄他培南的菌株的分布及抗生素耐药模式进行了回顾性分析。
我们旨在评估临床分离株的遗传相关性以及赋予耐厄他培南表型的潜在机制。
参与抗生素耐药的基因表达分析显示，主要的非选择性孔蛋白通道OmpK35表达降低。在除厄他培南外还对至少一种其他碳青霉烯类耐药的分离株中，OmpK36孔蛋白通道表达降低的程度较小。基因组DNA的脉冲场凝胶电泳分析表明，几乎所有分离株都属于同一遗传克隆。
对于耐厄他培南、碳青霉烯酶阴性且孔蛋白缺陷的肠杆菌科细菌突变体需谨慎对待，因为它们广泛存在，在选择性压力下可能导致局部克隆性暴发。
