School of Medicine, University of Zagreb, Zagreb, Croatia.
Clinical Department for Clinical and Molecular Microbiology, University Hospital Center Zagreb, Kišpatić Street 12, Zagreb, Croatia.
Arch Microbiol. 2021 May;203(4):1825-1831. doi: 10.1007/s00203-020-02161-x. Epub 2021 Jan 28.
Recently, emergence of carbapenem-resistance, in particular due to Klebsiella pneumoniae carbapenemase (KPC), was observed among K. pneumoniae causing urinary tract infections in Croatia. The aim of the study was to characterize, antimicrobial susceptibility, carbapenem resistance, virulence traits and plasmid types of the urinary KPC positive isolates of K. pneumoniae. The antimicrobial susceptibility to a wide range of antibiotics was determined by broth microdilution method. The transferability of meropenem resistance was determined by conjugation (broth mating method) employing Escherichia coli J63 strain resistant to sodium azide. Genes encoding broad and extended-spectrum β-lactamases, plasmid-mediated AmpC β-lactamases, group A and B carbapenemases, and carbapenem hydrolyzing oxacillinases (bla), respectively, were determined by Polymerase chain reaction (PCR). In total 30 KPC-positive K. pneumoniae urinary isolates collected from different regions of Croatia were analysed. The isolates were uniformly resistant to all tested antibiotics except for variable susceptibility to gentamicin, sulphamethoxazole/trimethoprim, and colistin, respectively. Four isolates were resistant to colistin with MICs values ranging from 4 to 16 mg/L. All tested isolates were susceptible to ceftazidime/avibactam. Sixteen isolates transferred meropenem resistance to E. coli recipient strain by conjugation. Other resistance markers were not co-transferred. PCR was positive for bla and bla genes in all isolates whereas 13 isolates tested positive also for bla genes. PCR based replicon typing (PBRT) revealed the presence of FIIs in 13 and FIA plasmid in two strains. The study showed dissemination of KPC-producing K. pneumoniae in urinary isolates, posing a new epidemiological and treatment challenge. Sulphamethoxazole/trimethoprim, colistin, and ceftazidime/avibactam remain so far, as the therapeutic options.
最近，在克罗地亚引起尿路感染的肺炎克雷伯菌中，观察到碳青霉烯类耐药性的出现，特别是由于产碳青霉烯酶肺炎克雷伯菌（KPC）。本研究的目的是对产碳青霉烯酶肺炎克雷伯菌的尿分离株进行特征描述、抗菌药物敏感性、碳青霉烯类耐药性、毒力特征和质粒类型分析。采用肉汤微量稀释法测定对多种抗生素的抗菌药物敏感性。采用携带对叠氮化钠耐药的大肠杆菌 J63 菌株的接合（肉汤交配法）测定美罗培南耐药的可转移性。采用聚合酶链反应（PCR）分别检测广谱和超广谱β-内酰胺酶、质粒介导的 AmpCβ-内酰胺酶、A 组和 B 组碳青霉烯酶以及碳青霉烯水解青霉素酶（bla）基因。总共分析了来自克罗地亚不同地区的 30 株产 KPC 肺炎克雷伯菌尿分离株。除对庆大霉素、磺胺甲恶唑/甲氧苄啶和黏菌素的敏感性不同外，这些分离株对所有测试的抗生素均具有一致性耐药性。4 株分离株对黏菌素耐药，MIC 值范围为 4-16mg/L。所有测试的分离株对头孢他啶/阿维巴坦均敏感。16 株分离株通过接合将美罗培南耐药性转移给大肠杆菌受体株。其他耐药标记物未同时转移。PCR 对所有分离株 bla 和 bla 基因均呈阳性，而 13 株分离株 bla 基因也呈阳性。基于 PCR 的复制子分型（PBRT）显示 13 株存在 FIIs 和 2 株存在 FIA 质粒。该研究表明，产 KPC 肺炎克雷伯菌在尿分离株中传播，带来了新的流行病学和治疗挑战。磺胺甲恶唑/甲氧苄啶、黏菌素和头孢他啶/阿维巴坦至今仍是治疗选择。
