伊朗烧伤患者分离的耐甲氧西林金黄色葡萄球菌菌株的遗传多样性研究：ST239-SCCmec III / t037作为主要克隆出现
发布者：抗性基因网 时间：2018-05-28 浏览量：1024
摘要
耐甲氧西林金黄色葡萄球菌（MRSA）是医疗保健，医院和社区环境中感染的主要原因，是全球健康问题。这项研究的目的是确定在伊朗首都德黑兰的一家烧伤医院MRSA的抗生素敏感性模式和循环分子类型的分布。在为期10个月的研究期间，评估了106株金黄色葡萄球菌分离株。使用纸片扩散法和聚合酶链式反应（PCR）对分离物进行敏感性测试以检测mecA，fem和nuc基因。通过PCR方法确定PVL和tst编码基因的存在。通过多位点序列分型（MLST），spa分型，SCCmec分型和agr分型对所有MRSA分离株进行基因分型。 mecA基因的存在在所有金黄色葡萄球菌分离株中均得到确认。抗生素敏感性试验显示对氨苄青霉素，四环素和红霉素的耐药率高（90.6％）。对剩余抗生素的耐药率在18.9％和84.9％之间。从烧伤患者中分离出的19.8％的MRSA菌株证实了高水平的莫匹罗星耐药性。在90.6％的分离株中观察到多重耐药性。 106个MRSA分离株中有16个（15.1％）携带PVL编码基因。我们大多数MRSA菌株携带SCCmec III（71.7％）。 ST239-SCCmec III / t037（34％）是最常见的基因型，其次是ST239-SCCmec III / t030（24.5％），ST15-SCCmec IV / t084（15.1％），ST22-SCCmec IV / t790（13.2％和ST239-SCCmec III / t631（13.2％）。莫匹罗星抗性MRSA分离物属于ST15-SCCmec IV / t084（40％），ST22-SCCmec IV / t790（23.3％），ST239-SCCmec III / t631（20％）和ST239-SCCmec III / t030（16.7％）克隆。结果显示，基因多样性MRSA菌株在我们的烧伤医院中循环，ST239-SCCmec III / t037克隆的相对高发病率。这些发现支持定期监测MRSA以确定现有MRSA克隆的分布并检测新MRSA克隆的出现的需要。
Methicillin-resistant Staphylococcus aureus (MRSA) as a major cause of infection in health care, hospital and community settings is a global health concern. The purpose of this study was to determine the antibiotic susceptibility pattern and distribution of circulating molecular types of MRSA in a burn hospital in Tehran, the capital of Iran. During a 10-month study period, 106 Staphylococcus aureus isolates were assessed. Isolates were subjected to susceptibility testing using the disk diffusion method andPolymerase Chain Reaction (PCR) for detection of mecA, fem and nuc genes. The presence of PVL and tst encoding genes were determined by PCR method. All the MRSA isolates were genotyped by multilocus sequence typing (MLST), spa typing, SCCmec typing and agr typing. The presence of mecA gene was confirmed in all theStaphylococcus aureus isolates. Antimicrobial susceptibility testing revealed a high resistance rate (90.6%) to ampicillin, tetracycline, and erythromycin. The rates of resistance to remaining antibiotics tested varied between 18.9% and 84.9%. The high- level of resistance to mupirocin was confirmed in 19.8% of MRSA strains isolated from burn patients. Multi-drug resistance was observed in 90.6% of isolates. Sixteen of the 106 MRSA isolates (15.1%) harbored PVL-encoding genes. The majority of our MRSA strains carried SCCmec III (71.7%). ST239-SCCmec III/t037 (34%) was the most common genotype followed by ST239-SCCmec III/t030 (24.5%), ST15-SCCmecIV/t084 (15.1%), ST22-SCCmec IV/t790 (13.2%), and ST239-SCCmec III/t631 (13.2%). Mupirocin resistant MRSA isolates belonged to ST15-SCCmec IV/t084 (40%), ST22-SCCmec IV/t790 (23.3%), ST239-SCCmec III/t631 (20%), and ST239-SCCmec III/t030 (16.7%) clones. The results showed that genetically diverse strains of MRSA are circulating in our burn hospitals with relatively high prevalence of ST239-SCCmec III/t037 clone. The findings support the need for regular surveillance of MRSA to determine the distribution of existing MRSA clones and to detect the emergence of new MRSA clones.
https://www.sciencedirect.com/science/article/pii/S0882401016305447
