克氏原鳌虾产ESBLs大肠杆菌的分离鉴定与耐药研究

Study on Antibiotic resistance of Extended-Spectrum β-lactamases in Escherichia coli isolated from Procambarus clarkii

关键词:  克氏原螯虾  产ESBLs大肠杆菌  多重耐药

Key words:  Procambarus clarkii  ESBLs-producing E. coli  multi-drug resistance

摘要:

为了解克氏螯虾产ESBLs大肠杆菌的流行情况，本研究采集来自山东、江苏、浙江、湖北和辽宁五个地区共198份小龙虾肠道样品，利用头孢噻肟选择性培养基和PCR方法筛选产ESBLs大肠杆菌；用BD PhoenixTM-100全自动微生物鉴定/药敏系统对分离的大肠杆菌进行生化鉴定和抗生素药敏检测。结果，从198份克氏螯虾样品中共分离获得107株产ESBLs大肠杆菌，分离率为54.0%。所有分离菌株对青霉素类和一代头孢完全耐药；对四环素类药物的耐药率为93.5%（100/107）；对三代头孢菌素、氟喹诺酮类、氯霉素类和磺胺类药物的耐药率均在60% 以上（>65株）；对氨基糖苷类、哌拉西林-他唑巴坦和阿莫西林-克拉维酸药率较低，对碳青霉烯类敏感；其中多重耐药（R≥3）菌株有96株，占86.7%，且以5重耐药（30%，31/107)和6重耐药（28%，30/107)为主。本研究获得了克氏螯虾产ESBLs大肠杆菌流行病学基础数据，发现五个地区的小龙虾体内大肠杆菌耐药水平高，耐药丰度大；反映了克氏螯虾大肠杆菌严重的耐药现状，为克氏螯虾细菌耐药性防控和水产品公共卫生监测奠定了基础。

Abstract:

In order to explore the prevalence of ESBLs producing E. coli and the status of antibiotic resistance in procambarus clarkii this study collected 107 ESBLs producing E. coli isolated from 198 procambarus clarkiis from five areas in China (Shandong, Jiangsu, Zhejiang, Dalian, Hubei). Antimicrobial susceptibility and ESBLs for 107 E. coli stains by determinated by cefotaxime containing medium, PCR and BD PhoenixTM-100 system. The results showed there were 54% of E. coli strains produced ESBLs. All ESBLs-producing E. coli stains were absolutely resistant to penicillins and first generation cephalosporins, 93.5%(100/107)were resistance to tetracyclines. The average resistance rate to third generation cephalosporins, the fluoroquinolones, chloramphenicols and sulfonamides is above 65%(>65/107). The rate of resistance to aminoglycosides and piperacillin/tazobactam, amoxicillin/ clavulanate was lower. All strains were sensitive to the carbapenems. Among these ESBLs-producing E. coli strains. The percentage of multiple drug resistance (R≥3) isolates were 96, 86.7%, five kinds of drug resistance(30%,31/107) and six kinds of drug resistance (28%,30/107) were predominated . The study provided basic epidemiological data about ESBLs-producing E.coli, discovered the high level of drug resistance and abundant multiple- resistacne genes in E. coli of procambarus clarkii from five areas. Futhermore it showed seriousness of antibiotic resistance in E.coli from procambarus clarkii. All the results were beneficial for monitoring public hygiene of aquatic product.