北京市食源性耐甲氧西林的金黄色葡萄球菌的分子特征研究

Research on molecular characteristics of foodborne Methicillin-resistant Staphylococcus aureus in Beijing

目的分析近年来北京市食品中对甲氧西林耐药的金黄色葡萄球菌(MRSA)的脉冲场凝胶电泳(PFGE)图谱特征。方法收集2010年-2012年北京地区食品中分离到的金黄色葡萄球,采用微量肉汤稀释法进行耐药检测,对分离到的MRSA进行PFGE分型。结果 52株对甲氧西林耐药的金黄色葡萄球菌对其他抗生素耐药率为红霉素(ERY)53.85%;四环素(TET)23.08%;克林霉素(CLI)23.08%;氯霉素(CHL)9.62%;甲氧苄啶/磺胺甲恶唑(TPM/SMZ)9.62%;环丙沙星(CIP)1.92%。其中34株菌表现为多重耐药,占MRSA菌株65.38%,表现出16种耐药谱。52株对甲氧西林耐药的金黄色葡萄球菌共分为34种PFGE带型,优势带型不明显。结论北京市食源性MRSA的耐药谱多样,多重耐药普遍存在。PFGE带型分布广泛,菌株PFGE带相同但耐药谱存在差异,而耐药谱相同的菌株中带型间又存在差异,两者间未表现出相关性。

Objective To study the molecular pattern characteristics of Methicillin-Resistant Staphylococcus aureus（MRSA） isolated from food samples by pulsed-field gel electrophoresis（PFGE） in Beijing in recent years.Methods To detect the antibiotic resistance of Staphylococcus aureus isolated from food in Beijing from 2010 to 2012 by broth micro-dilution method so as to confirmed the MRSA.The isolates were further typed by PFGE.Results The resistance rates to other antibiotics of 52 MRSA strains were Erythromycin（53.85%）,Tetracycline（23.08%）,Clindamycin（23.08%）,Chloramphenicol（9.62%）,Trimethoprim/Sulfamethoxazole（9.62%）,Ciprofloxacin（1.92%）.The 34 MRSA strains were multidrug resistant,multidrug-resistant MRSA strains accounted for 65.38% of all MRSA strains.All of the MRSA trains showed 16 kinds of resistance spectrum.Totally,34 PFGE patterns were identified with diffused distribution.No dominant PFGE patterns were obviously identified.Conclusion The antibiotic resistance spectrum of foodborne MRSA in Beijing is multiformity.Multidrug resistance were popular among the MRSA strains isolated from food.The PFGE patterns of food borne MRSA strains in Beijing showed wide distribution characteristics.The strains which have the same PFGE patterns showed different antibiotic resistance spectrum,the strains which have the same antibiotic resistance spectrum showed different PFGE patterns.The antibiotic resistance spectrum and PFGE patterns showed no correlation.