PDF(Pubmed)
Abstract：
We determined antibiotic susceptibility and employed Oxford Nanopore whole-genome sequencing to explore strain diversity, resistance, and virulence gene carriage among methicillin-resistant Staphylococcus aureus (MRSA) strains from different infection sites and timepoints in a tertiary Kenyan hospital. Ninety-six nonduplicate clinical isolates recovered between 2010 and 2023, identified and tested for antibiotic susceptibility on the VITEK ID/AST platform, were sequenced. Molecular typing, antibiotic resistance, and virulence determinant screening were performed using the relevant bioinformatics tools. The strains, alongside those from previous studies, were stratified into two periods covering 2010-2017 and 2018-2023 and comparisons were made. Mirroring phenotypic profiles, aac(6\')-aph(2″) [aminoglycosides]; gyrA (S84L) and grlA (S80Y) [fluoroquinolones]; dfrG [anti-folates]; and tet(K) [tetracycline] resistance determinants dominated the collection. While the proportion of ST239/241-t037-SCCmec III among MRSA reduced from 37.7% to 0% over the investigated period, ST4803-t1476-SCCmec IV and ST152-t355-SCCmec IV were pre-eminent. The prevalence of Panton-Valentine leucocidin (PVL) and arginine catabolic mobile element (ACME) genes was 38% (33/87) and 6.8% (6/87), respectively. We observed the displacement of HA-MRSA ST239/241-t037-SCCmec III with the emergence of ST152-t355-SCCmec IV and a greater clonal heterogeneity. The occurrence of PVL+/ACME+ CA-MRSA in recent years warrants further investigations into their role in the CA-MRSA virulence landscape, in a setting of high PVL prevalence.
摘要：
我们确定了抗生素敏感性，并采用牛津纳米孔全基因组测序来探索菌株多样性，阻力,在肯尼亚一家三级医院中，来自不同感染部位和时间点的耐甲氧西林金黄色葡萄球菌（MRSA）菌株中的毒力基因携带。在2010年至2023年之间恢复了96种非重复临床分离株，在VITEKID/AST平台上进行了鉴定和抗生素敏感性测试，被测序。分子分型,抗生素耐药性,使用相关的生物信息学工具进行毒力决定子筛选。菌株，与以前的研究一样，分为2010-2017年和2018-2023年两个时期，并进行了比较。反映表型概况，aac（6'）-aph（2“）[氨基糖苷]；gyrA（S84L）和grlA（S80Y）[氟喹诺酮]；dfrG[抗叶酸]；和tet（K）[四环素]抗性决定因素占主导地位。虽然在调查期间，MRSA中ST239/241-t037-SCCmecIII的比例从37.7%降至0%，ST4803-t1476-SCCmecIV和ST152-t355-SCCmecIV是杰出的。Panton-Valentineleucocidin(PVL)和精氨酸分解代谢移动因子(ACME)基因的患病率分别为38%(33/87)和6.8%(6/87),分别。我们观察到HA-MRSAST239/241-t037-SCCmecIII的置换随着ST152-t355-SCCmecIV的出现和更大的克隆异质性。近年来PVL+/ACME+CA-MRSA的发生值得进一步研究它们在CA-MRSA毒力环境中的作用。在高PVL患病率的背景下。
