外科住院患者感染耐甲氧西林凝固酶阴性葡萄球菌的耐药基因检测及耐药性分析  

Detection of drug resistance genes and analysis of drug resistance in methicillin-resistant coagulase-negative staphylococci infecting surgical patients in Nanjing

作　　者：慕海峰[1] 燕占甫 王春[1] 高乃荣[1] 

机构地区：[1]东南大学医学院附属同仁医院,江苏南京211100

出　　处：《中国病原生物学杂志》2014年第5期461-465,共5页Journal of Pathogen Biology

基　　金：国家卫计委(原卫生部)创新计划课题资助项目(No.MIT1182)

摘　　要：目的对南京市外科住院患者感染的耐甲氧西林凝固酶阴性葡萄球菌的耐药相关基因进行检测,以更好地控制病原菌耐药性,减少外科感染。方法从南京市多家医院外科住院患者各类临床标本分离耐甲氧西林凝固酶阴性葡萄球菌70株,经纯培养获单菌落后进行鉴定,并进行药敏试验,然后对耐药基因进行PCR测序,对PCR扩增产物进行电泳检测并记录。结果耐甲氧西林凝固酶阴性葡萄球菌对于头孢噻肟和红霉素100%耐药,对万古霉素耐药率为0,对其他抗菌药物的耐药率大小依次为:左氧氟沙星>诺氟沙星>氨苄西林>妥布霉素>环丙沙星>克林霉素>头孢曲松>庆大霉素>四环素>利福平。PCR检测耐药基因,3株只携带mecA 1种耐药基因。15株携带2种耐药基因,分别为:ermA+mecA、aac(6′)/aph(2′′)+mecA和aph(3′)-III+mecA和tetM+mecA。29株携带3种耐药基因,携带方式分别为:ermA+aac(6′)/aph(2′′)+mecA、aph(3′)-III+ermA+mecA、ermA+tetM+mecA、aac(6′)/aph(2′′)+aph(3′)-III+mecA、aac(6′)/aph(2′′)+tetM+mecA和tetM+aph(3′)-III+mecA。20株携带4种耐药基因,携带方式分别为:aac(6′)/aph(2′′)+tetM+ermA+mecA、aph(3′)-III+tetM+aac(6′)/aph(2′′)+mecA、aph(3′)-III+tetM+ermA+mecA和aph(3′)-III+aac(6′)/aph(2′′)+ermA+mecA。有3株携带5种耐药基因,即ermA+aph(3′)-III+tetM+aac(6′)/aph(2′′)+mecA。结论耐甲氧西林凝固酶阴性葡萄球菌对常用抗菌药物的耐药性普遍较高,5种耐药基因在菌株中出现的频率不同,但所有病原菌都存在mecA基因,因而该菌的耐药性可能与mecA基因有关。Objectives To detect drug resistance genes and analyze the drug resistance of methicillin-resistant coagulase-negative staphylococci infecting surgical patients in Nanjing in order to better control the drug resistance of pathogens and reduce surgical infection. Methods Seventy strains of methicillin-resistant coagulase-negative staphylococci were isolated from clinical specimens from surgical patients at hospitals in Nanjing. After pure culturing, single colonies were obtained to identify staphylococci and test their drug susceptibility. Drug resistance genes were sequenced using PCR, and PCR-amplified products were de- tected using electrophoresis and recorded. Results Methicillin-resistant coagulase-negative staphylococci had a resistance to ce- fotaxime and erythromycin of 100 ~ and a resistance to vancomycin of 0. Staphylococci were most resistant to levofloxacin, highly resistant to norfloxacin, highly resistant to ampicillin, highly resistant to tobramycin, somewhat resistant to ciprofloxacin, some- what resistant to clindamyein, somewhat resistant to ceftriaxone, slightly resistant to gentamicin, slightly resistant to tetracycline, and least resistant to rifampicin. Drug resistance genes were detected using PCR, and only 3 strains were found to carry a form of the mecA gene for drug resistance. Fifteen 15 strains carried 2 drug resistance genes, i.e. ermAq-mecA, aac（6′）/aph （2″） ＋mecA, aph（3r）-Ⅲ ±mecA, or tetM＋mecA. Twenty-nine strains carried 3 drug resistance genes, i.e. ermAq-aae（6′）/ aph（2″）±mecA, aph（3r）-Ⅲ＋ermA＋mecA, ermA＋tetM＋meeA, aac（61）/aph（2″）q-aph（3r）-Ⅲ＋mecA, aac（6r）/aph（2″） ＋tetMq-mecA, or tetM＋aph（3＇）-Ⅲ＋mecA. Twenty 20 strains carried 4 drug resistance genes, i.e. aac（6r）/aph（2″）＋tetM ＋ermA＋mecA, aph（3t）-ⅢtetM＋aac（6′）/aph（2″）＋mecA, aph（3′）-Ⅲ＋tetM＋ermA＋mecA, or aph（3＇）-III＋aac（6r）/ aph （ 2 r ） ＋ ermA＋ mecA. Three strains carried 5

关 键 词：外科 耐甲氧西林凝固酶阴性葡萄球菌 耐药基因 药敏实验 基因检测 

分 类 号：R378.11[医药卫生—病原生物学]