禽大肠埃希菌耐药谱及氨基糖苷耐药基因分子流行病学调查

Antibiotics resistance and molecular epidemiology of aminoglycoside resistant gene in avian pathogenic E.coli

为了明确禽大肠埃希菌的耐药情况和氨基糖苷抗性基因的流行情况,用K-B纸片扩散法检测了27株致病性大肠杆菌对19种常用抗生素的耐药谱,用PCR方法检测了耐氨基糖苷抗生素分离株的4种氨基糖苷抗性基因,包括腺苷转移酶基因aadA1和aadB、乙酰转移酶基因aacA4和磷酸转移酶基因apH(3′)-Ⅱ。结果表明,氨苄青霉素、安灭菌、青霉素G和四环素的耐药菌株率高达100%,利福平的耐药菌株率达96.3%,氯霉素、红霉素的耐药菌株为70.4%,卡那霉素、环丙沙星、氟哌酸的耐药菌株率为59.3%,链霉素的耐药菌株达到63.0%。氨苄西林/舒巴坦复方制剂、复达欣、庆大霉素和磷霉素的高敏菌株率分别为100%、77.8%、74.1%和51.9%。氨基糖苷抗性基因aadA1、aacA4和apH(3′)-Ⅱ的阳性率分别是44.4%、27.8%和55.6%,aadB未捡出。这些数据提示禽致病性大肠埃希菌存在广泛的耐药谱,氨基糖苷抗性基因aadA1和apH-(3′)-Ⅱ是主要流行基因。

In order to investigate the patterns of antibiotic resistance and prevalence of aminoglycoside resistant genes in pathogenic E. coli isolated from poultry, K-B disk diffusion method was used to detect the susceptibility of 27 E. coli isolates to 19 kinds of antimicrobial agents, and 4 aminoglycoside resistant genes of aminoglycoside adenyltransferases aadA1 and aadB, aminoglycoside phosphorylases apH （3＇）-Ⅱ and aminoglycoside acetyltransferases aac A4 were detected by using PCR. Results indicated that the resistance strains of 27 isolates to ampicillin,amoxicillin,penicillin G and tetracin were 100%, and that to rifampicin, chloromycin, erythromycin, Kanamycin, ciproftoxacin, norfloxacin and ：Streptomycin were 96. 3%, 70.4%, 70.4%, 59.26%, 59.3%, 59.3%, and 63.0%, respectively. The percentage of sensitive E. coli isolates to Ampicillin/sulbactan, Fortum, Gentamicin and Fosfomycin were 100%, 77. 8%, 74. 1% and 51.9%, respectively. PCR results showed that 44.4%,27.8% and 55.6% of the tested isolates were positive for aadAl,aacA4 and apH（3P）- Ⅱ ,respectively. The aadB gene was not detected. These data showed that the spectrum of drug-resistance of avian pathogenic E. coli was very broad, and the aminoglycoside resistance gene of apH（3＇）-Ⅱ and aadA1 were leading prevalence genes.