临床分离耐甲氧西林金黄色葡萄球菌的耐药性及分子流行病学研究

Resistance to antibacterial and molecular epidemiology profile of methicillin-resistant Staphylococcus aureus clinical isolates

目的研究我国临床分离的耐甲氧西林金黄色葡萄球菌(MRSA)的耐药性及分子流行病学特点。方法菌株来源于全国17家医院分离的MRSA共计160株,用标准平皿二倍稀释法测定对23种抗菌药物的最低抑菌浓度(M IC);用脉冲场凝胶电泳技术(PFGE)对其中133株MRSA菌株进行同源性分析。结果 160株MRSA对多种抗菌药物呈现不同程度的耐药。其中,133株MRSA菌株的PFGE图谱显示,共有A～E 5种类型,以A型为主,为88株(A1型27株,A2型25株,A3型22株,A4型12株,A5型2株);B型为25株(B1型19株,B2型3株,B3、B4和B5型各1株);C型为8株(C1型7株,C2型1株);另有12株为散发菌株。结论临床分离的MRSA呈多重耐药性,我国不同医院流行的MRSA菌株基因型主要为A1、A2、A3和B1型;且不同地区的医院流行的菌株基因型不同,同一医院流行的菌株基因型也不同。

Objective To investigate the resistance to antibacterial and molecular epidemiology profile of methicillin-resistant Staphylococcus aureus（MRSA） clinical isolates.Methods One hundred sixty strains of MRSA were colleted from the 17 hospitals in China.The minimal inhibitory concentration（MIC） to 23 antibacterial was determined by agar dilution method.Pulsed-field gel electrophoresis（PFGE） was used to type the chromosome DNA of MRSA isolates.Results One hundred sixty MRSA isolates showed different resistant phenotypes to various antimicrobial agents.Five different PFGE patterns（A-E） were found among 133 MRSA strains.Most of MRSA were A pulsotype（88 strains）.A pulsotype included A1 subtype（27 strains）,A2 subtype（25 strain）,A3 subtype（22 strain）,A4 subtype（12 strain） and A5 subtype（2 strain）.B pulsotype included B1 subtype（19 strains）,B2 subtype（3 strain）,B3,B4 and B5 subtype（1 strain）,respectively.C pulsotype included C1 subtype（7 strains）,C2 subtype（1 strain）.There were 12 diverging strains.Conclusion MRSA from clinical isolates was multi-resistant to antibacterial.The epidemiology profile of MRSA was A1,A2,A3 and B1 subtype in China.The type chromosome DNA of MRSA in different hospital was difference,and also difference in different area.