Department of Medical Microbiology and Parasitology, College of Basic Medical Sciences, China Medical University, Shenyang, People's Republic of China.
Braz J Infect Dis. 2013 Nov-Dec;17(6):682-90. doi: 10.1016/j.bjid.2013.02.007. Epub 2013 Jul 31.
In order to obtain adequate information for the treatment of methicillin resistant Staphylococcus aureus (MRSA) infections, it is crucial to identify trends in epidemiological and antimicrobial resistance patterns of local S. aureus strains. Community and hospital acquired S. aureus isolates (n=202) were characterized using staphylococcal cassette chromosome mec (SCCmec) typing, pulse field gel electrophoresis (PFGE) analysis, spa typing and minimal inhibitory concentration (MIC) determination. The prevalence of the Panton-Valentine leukocidine (pvl) and several antibiotic resistance genes among the isolates were also detected by PCR. All of the S. aureus isolates were susceptible to vancomycin, daptomycin and linezolid. Three hospital isolates were resistant to teicoplanin while 14 showed intermediate resistance to teicoplanin. The resistance patterns of community-acquired MRSA (CA-MRSA) isolates to other antimicrobials were similar to those of hospital-acquired MRSA (HA-MRSA) isolates except for clindamycin and gentamicin. There was excellent correlation between phenotypes and genotypes in the determination of S. aureus resistance to erythromycin, gentamicin, and tetracycline. The SCCmec type II and SCCmec type IV were the predominant types detected in hospital and community isolates, respectively. The most frequently encountered spa types were t002 and t030 both in HA- and CA-MRSA isolates. Pulsotype A was the most predominant pulsotype identified among the isolates tested, followed by pulsotype B. Seventy-two hospital isolates (19 HA-MRSA and 53 HA-MSSA) and 10 CA-MRSA were positive for the pvl gene. This study shows that the combination of susceptibility testing and various molecular methods has provided useful information on the antibiotic resistance and molecular diversity of S. aureus in a specific region of China. The high proportion of pvl positive MSSA and MRSA isolates observed in this study indicates that adequate measures are needed to curtail the spread of those MRSA and MSSA clones prevailing both in hospital and the community.
为了获得治疗耐甲氧西林金黄色葡萄球菌（MRSA）感染的充分信息，确定当地金黄色葡萄球菌菌株的流行病学和抗菌耐药模式趋势至关重要。使用葡萄球菌盒式染色体 mec（SCCmec）分型、脉冲场凝胶电泳（PFGE）分析、spa 分型和最小抑菌浓度（MIC）测定对社区和医院获得性金黄色葡萄球菌分离株（n=202）进行了特征描述。还通过 PCR 检测了分离株中潘顿-瓦伦丁白细胞毒素（pvl）和几种抗生素耐药基因的存在。所有金黄色葡萄球菌分离株均对万古霉素、达托霉素和利奈唑胺敏感。3 株医院分离株对替考拉宁耐药，14 株对替考拉宁表现为中介耐药。社区获得性 MRSA（CA-MRSA）分离株对其他抗菌药物的耐药模式与医院获得性 MRSA（HA-MRSA）分离株相似，除了克林霉素和庆大霉素。在确定金黄色葡萄球菌对红霉素、庆大霉素和四环素的耐药性时，表型和基因型之间存在极好的相关性。SCCmec 型 II 和 SCCmec 型 IV 分别是医院和社区分离株中主要检测到的类型。在 HA-MRSA 和 CA-MRSA 分离株中最常见的 spa 型是 t002 和 t030。在测试的分离株中，最常见的脉冲型是 A，其次是 B。72 株医院分离株（19 株 HA-MRSA 和 53 株 HA-MSSA）和 10 株 CA-MRSA 携带 pvl 基因呈阳性。本研究表明，药敏试验和各种分子方法的结合为中国特定地区金黄色葡萄球菌的抗生素耐药性和分子多样性提供了有用信息。本研究中观察到的 pvl 阳性 MSSA 和 MRSA 分离株比例较高，表明需要采取充分措施来遏制这些 MRSA 和 MSSA 克隆在医院和社区中的传播。
