Tsergouli Katerina, Karampatakis Theodoros, Kontopoulou Konstantina, Pappa Styliani, Kampouridou Parthena, Kallasidou Georgia, Tsioka Katerina, Zotou Sophia, Farmaki Εleftheria-Eugenia, Kotzamanidis Charalampos, Papa Anna
1Department of Microbiology, Medical Faculty, School of Health Sciences, Aristotle University of Thessaloniki, Greece.
2Department of Microbiology, "Georgios Gennimatas" General Hospital of Thessaloniki, Greece.
Acta Microbiol Immunol Hung. 2022 Aug 29;69(3):185-192. doi: 10.1556/030.2022.01825. Print 2022 Sep 16.
Methicillin-resistant Staphylococcus aureus (MRSA) causes severe community and hospital acquired infections. Identification of staphylococcal cassette chromosome mec (SCCmec), multilocus-sequence typing, and sequencing of S. aureus protein A (spa) gene are used for MRSA typing. The aim was to investigate the spa types of MRSA isolates in a tertiary hospital in Greece and analyse the whole genome sequences of two t127 MRSA isolates.
Totally, 39 MRSA isolates collected from July 2019 to June 2020 in "Georgios Gennimatas" General Hospital of Thessaloniki, Greece, were included in the study. Identification and antimicrobial susceptibility testing were performed using VITEK II automated system, and spa typing was performed. A minimum spanning tree was used to display the spa type frequencies and the genetic distances among them. Two t127-MRSA isolates (IM-MRSA and PD-MRSA) were selected for WGS.
Six isolates (15.4%) were resistant to mupirocin, 18 (46.2%) to fusidic acid, three (7.7%) to vancomycin and two (5.1%) to teicoplanin. Twenty-two different spa types were detected, with t002, t003, and t422 being the most frequent (5/39, 12.8% each), followed by t1994 (4/39, 10.3%). The isolates presented high genetic diversity and, taking into account the time between hospital admission and sampling, intrahospital spread did not occur. Even the two t127 isolates were assigned to different sequence types, ST9-XII-t127 and ST1-IVa-t127. Plasmids and genes conferring antimicrobial resistance and virulence were also identified.
Various spa types were identified and together with the information about the time between hospital admission and sampling supports polyclonal MRSA spread in the hospital excluding a nosocomial infection. WGS provides a more detailed analysis distinguishing even the isolates belonging to the same spa type.
耐甲氧西林金黄色葡萄球菌（MRSA）可引起严重的社区获得性感染和医院获得性感染。葡萄球菌盒式染色体mec（SCCmec）鉴定、多位点序列分型以及金黄色葡萄球菌蛋白A（spa）基因测序用于MRSA分型。本研究旨在调查希腊一家三级医院中MRSA分离株的spa分型，并分析两株t127型MRSA分离株的全基因组序列。
本研究纳入了2019年7月至2020年6月期间在希腊塞萨洛尼基“乔治奥斯·根尼马塔斯”综合医院收集的39株MRSA分离株。使用VITEK II自动化系统进行鉴定和抗菌药物敏感性测试，并进行spa分型。使用最小生成树展示spa分型频率及其之间的遗传距离。选择两株t127型MRSA分离株（IM-MRSA和PD-MRSA）进行全基因组测序（WGS）。
6株分离株（15.4%）对莫匹罗星耐药，18株（46.2%）对夫西地酸耐药，3株（7.7%）对万古霉素耐药，2株（5.1%）对替考拉宁耐药。检测到22种不同的spa分型，其中t002、t003和t422最为常见（各占5/39，12.8%），其次是t1994（4/39，10.3%）。这些分离株呈现出高度的遗传多样性，考虑到入院与采样之间的时间间隔，未发生医院内传播。即使是两株t127分离株也被归为不同的序列型，即ST9-XII-t127和ST1-IVa-t127。还鉴定出了携带抗菌药物耐药性和毒力的质粒及基因。
鉴定出了多种spa分型，结合入院与采样之间的时间信息，支持MRSA在医院内多克隆传播而非医院感染。全基因组测序提供了更详细的分析，甚至能区分属于同一spa分型的分离株。
