Mohamed Fatma A, Timmer Bálint, Hargitai Renáta, Melegh Szilvia, Meszéna Réka, Pál Tibor, Urbán Péter, Herczeg Róbert, Gyenesei Attila, Sonnevend Ágnes
Department of Medical Microbiology and Immunology, University of Pécs Medical School, Pécs, Hungary.
Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt.
Microbiol Spectr. 2025 Sep 2;13(9):e0003125. doi: 10.1128/spectrum.00031-25. Epub 2025 Aug 4.
Hypervirulent (hvKP) can cause severe infections even in healthy individuals. Currently, no data are available on the frequency of hvKP-induced bloodstream infections (BSI) in Hungary. Our investigation revealed that of the 157 . isolated from BSI in 2020-2022 at a university hospital in Hungary, three (2%) carried the hypervirulence-associated and genes. The complete genomes of these three hvKP isolates were sequenced. They were unrelated and belonged to ST5, ST86, and ST6771, a single-locus variant of ST893, i.e., to internationally known hvKP clones. In the ST86 and ST6771 isolates, the , aerobactin, and salmochelin siderophore genes were located on virulence plasmids highly similar to those of ST23 and ST86 isolated in Asia, while the ST5 isolate harboured , , and yersiniabactin locus on a chromosomally integrated ICE element. Comparison of the core genome MLST of the three Hungarian hvKP isolates to genomes belonging to the same ST/CC deposited in the Bigsdb database of the Pasteur Institute revealed that, although no direct epidemiological link could be established, KP48326 ST86, isolated in Pécs, clustered with a Greek isolate (ID-48733). The emergence of belonging to known hypervirulent clones in Hungary, albeit sporadic, is alarming and underscores the importance of continued whole-genome-based epidemiological surveillance.IMPORTANCEThis study represents the first investigation of the prevalence of hypervirulent (hvKP) in bloodstream infections in Hungary, conducted at the University Hospital of Pécs. Our findings emphasize the need to accurately identify hvKP strains, integrating both phenotypic and genotypic screening. Whole genome sequencing revealed genetic diversity among the Hungarian hvKP isolates, confirming the emergence of globally disseminating hvKP clones-ST86, CC893, and ST5-in Hungary. The localization of hypervirulence-related genes on mobile genetic elements, e.g., on virulence plasmids or on ICE similar to those found in hvKP isolates from different continents, underscores the significant role of horizontal gene transfer in the spread of hvKP. Overall, the study enhances our understanding of hvKP epidemiology and underscores the importance of continued molecular surveillance and control measures to mitigate the threat of hvKP infections in Hungary.
高毒力肺炎克雷伯菌（hvKP）即使在健康个体中也可引起严重感染。目前，匈牙利尚无关于hvKP引起的血流感染（BSI）发生率的数据。我们的调查显示，在匈牙利一家大学医院2020 - 2022年从BSI中分离出的157株肺炎克雷伯菌中，有3株（2%）携带与高毒力相关的 和 基因。对这三株hvKP分离株的全基因组进行了测序。它们互不相关，分别属于ST5、ST86和ST6771（ST893的单基因座变体，即国际上已知的hvKP克隆）。在ST86和ST6771分离株中， 、气杆菌素和沙门菌素铁载体基因位于与亚洲分离的ST23和ST86高度相似的毒力质粒上，而ST5分离株在染色体整合的ICE元件上携带 、 和耶尔森菌素基因座。将这三株匈牙利hvKP分离株的核心基因组多位点序列分型与保存在巴斯德研究所Bigsdb数据库中的属于同一ST/CC的基因组进行比较，发现尽管无法建立直接的流行病学联系，但在佩奇分离的KP48326 ST86与一株希腊分离株（ID - 48733）聚类。匈牙利出现属于已知高毒力克隆的菌株，尽管是散发性的，但令人担忧，并突出了持续进行基于全基因组的流行病学监测的重要性。重要性本研究是在佩奇大学医院对匈牙利血流感染中高毒力肺炎克雷伯菌（hvKP）的流行情况进行的首次调查。我们的研究结果强调了准确鉴定hvKP菌株的必要性，将表型和基因型筛查结合起来。全基因组测序揭示了匈牙利hvKP分离株之间的遗传多样性，证实了全球传播的hvKP克隆ST86、CC893和ST5在匈牙利的出现。高毒力相关基因在移动遗传元件上的定位，例如在毒力质粒上或与来自不同大陆的hvKP分离株中发现的ICE相似的元件上，突出了水平基因转移在hvKP传播中的重要作用。总体而言，该研究增进了我们对hvKP流行病学的理解，并突出了持续进行分子监测和控制措施以减轻匈牙利hvKP感染威胁的重要性。
