Tai Pei Wen, Huang Cheng Hua, Lin Qin Dong, Huang Yang Yang
Division of Infectious Diseases, Department of Internal Medicine, Cathay-General Hospital, Taipei, Taiwan.
J Microbiol Immunol Infect. 2006 Jun;39(3):225-30.
Methicillin-resistant Staphylococcus aureus (MRSA) infection has progressively increased worldwide. Knowledge of the specific epidemiological pattern of isolates at individual hospitals is important.
MRSA bacteremia was diagnosed in a total of 68 patients from January 2002 through December 2003, stratified for drug susceptibility and molecular pattern (staphylococcal cassette chromosome mec element [SCCmec] typing and genotypes).
SCCmec-A-positive isolates were found on polymerase chain reaction in 58 patients. The most frequent SCCmec types were III (40 cases) of which less than 5% were susceptible to other beta-lactam antibiotics and most were health care-associated, followed by SCCmec type IV (15 cases), that were demonstrated to be community-acquired. SCCmec type IV MRSA isolates were more likely to be susceptible to ciprofloxacin (93.3%), gentamicin (46.7%) and trimethoprim-sulfamethoxazole (93.3%) than type III isolates. All MRSA isolates were susceptible to glycopeptides and vancomycin (minimum inhibitory concentrations <2 microg/mL). Pulsed-field gel electrophoresis with SmaI digestion was used to fingerprint these isolates. A total of 9 genotypes with 26 type-subtypes were identified. Genotype A was the most frequent (9 subtypes) indicating that it is epidemic in this hospital.
After analysis, SCCmec typing could be used to predict drug susceptibility. Specific clones of S. aureus are circulating in hospital and communities in Taiwan.
耐甲氧西林金黄色葡萄球菌（MRSA）感染在全球范围内呈逐渐上升趋势。了解各医院分离株的具体流行病学模式很重要。
2002年1月至2003年12月期间，共诊断出68例MRSA菌血症患者，并根据药敏和分子模式（葡萄球菌盒式染色体mec元件[SCCmec]分型和基因型）进行分层。
通过聚合酶链反应在58例患者中发现了SCCmec - A阳性分离株。最常见的SCCmec类型为III型（40例），其中对其他β - 内酰胺类抗生素敏感的不到5%，且大多数与医疗保健相关，其次是IV型（15例），被证明是社区获得性的。IV型MRSA分离株比III型分离株更易对环丙沙星（93.3%）、庆大霉素（46.7%）和甲氧苄啶 - 磺胺甲恶唑（93.3%）敏感。所有MRSA分离株对糖肽类和万古霉素敏感（最低抑菌浓度<2μg/mL）。使用SmaI消化的脉冲场凝胶电泳对这些分离株进行指纹图谱分析。共鉴定出9种基因型，26种类型亚型。基因型A最常见（9个亚型），表明其在该医院呈流行状态。
经分析，SCCmec分型可用于预测药敏。金黄色葡萄球菌的特定克隆在台湾的医院和社区中传播。
