Kaneko Hiroshi, Yanagi Yuka, Otake Shogo, Sato Mayu, Saito Takumi, Nakaminami Hidemasa
Department of Clinical Microbiology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
J Antimicrob Chemother. 2023 Apr 3;78(4):1023-1027. doi: 10.1093/jac/dkad039.
Some MRSA strains produce Panton-Valentine leucocidin (PVL) and/or toxic shock syndrome toxin 1 (TSST-1), which are associated with severe infectious diseases. Although PVL- or TSST-1-positive strains have been isolated worldwide, strains carrying both PVL and TSST-1 genes are rare and sporadic. The objective of this study was to characterize these strains from Japan.
A total of 6433 MRSA strains isolated in Japan between 2015 and 2021 were analysed. Molecular epidemiological and comparative genomic analyses were conducted on PVL- and TSST-1-positive MRSA strains.
A total of 26 strains from 12 healthcare facilities were PVL positive and TSST-1 positive, and all were classified as clonal complex (CC) 22. These strains exhibited similar genetic features to each other and were named as ST22-PT according to a previous report. Twelve and one of the ST22-PT strains were identified in patients with deep-seated skin infections and toxic shock syndrome-like symptoms, which are typical clinical features of PVL-positive and TSST-1-positive Staphylococcus aureus, respectively. Whole-genome comparative analysis revealed that the ST22-PT strains were highly similar to PVL- and TSST-1-positive CC22 strains isolated in several countries. Evaluation of the genome structure showed that ST22-PT possessed ΦSa2 harbouring PVL genes and a unique S. aureus pathogenicity island harbouring the TSST-1 gene.
ST22-PT strains have recently emerged from several healthcare facilities in Japan, and ST22-PT-like strains have been identified in several countries. Our report highlights that the risk of international spread of PVL- and TSST-1-positive MRSA clone ST22-PT needs to be further investigated.
一些耐甲氧西林金黄色葡萄球菌（MRSA）菌株可产生杀白细胞素（PVL）和/或中毒性休克综合征毒素1（TSST-1），它们与严重感染性疾病有关。尽管PVL或TSST-1阳性菌株已在全球范围内分离得到，但同时携带PVL和TSST-1基因的菌株却很罕见且呈散发性。本研究的目的是对来自日本的这些菌株进行特征分析。
对2015年至2021年期间在日本分离出的6433株MRSA菌株进行分析。对PVL和TSST-1阳性的MRSA菌株进行分子流行病学和比较基因组分析。
来自12家医疗机构的26株菌株PVL阳性且TSST-1阳性，所有菌株均被归类为克隆复合体（CC）22。这些菌株彼此表现出相似的遗传特征，根据先前的报告被命名为ST22-PT。分别在深部皮肤感染患者和中毒性休克综合征样症状患者中鉴定出12株和1株ST22-PT菌株，这分别是PVL阳性和TSST-1阳性金黄色葡萄球菌的典型临床特征。全基因组比较分析显示，ST22-PT菌株与在多个国家分离出的PVL和TSST-1阳性CC22菌株高度相似。对基因组结构的评估表明，ST22-PT拥有携带PVL基因的ΦSa2和一个携带TSST-1基因的独特金黄色葡萄球菌致病岛。
ST22-PT菌株最近在日本的几家医疗机构中出现，并且在多个国家也鉴定出了类似ST22-PT的菌株。我们的报告强调，PVL和TSST-1阳性MRSA克隆ST22-PT的国际传播风险需要进一步研究。
