金黄色葡萄球菌食品分离株耐药谱研究

Study of Antimicrobial Resistance and Inducible Resistance of Erythromycin and Clindamycin in Staphylococcus aureus Isolated from Food Samples

目的调查2007年深圳市分离自生熟食品及餐具中金黄色葡萄球菌的耐药情况及对红霉素和克林霉素的诱导耐药性。方法用国标方法分离鉴定金黄色葡萄球菌,VITEK2 Compact生化验证,用K-B法进行药敏试验,用D试验检测红霉素对克林霉素的诱导耐药性。结果从食品及餐具涂抹拭子中分离的53株金黄色葡萄球菌对青霉素G、氨苄西林及阿莫西林/棒酸表现很高的耐药性,耐药率达80%以上;对万古霉素、替考拉宁、甲氧西林、氨苄西林/舒巴坦、头孢唑啉、头孢噻吩、头孢西丁7种药物均敏感;对红霉素和克林霉素同时耐药占11.3%。D试验阳性占所检测菌株11.3%;在单一纸片红霉素耐药(中介)而克林霉素敏感的菌株中,D试验阳性即对克林霉素具有诱导耐药性为25%。结论金黄色葡萄球菌食品分离株绝大部分为MSSA,除青霉素类外耐药率较低;在红霉素耐药(中介)、克林霉素敏感菌株中克林霉素诱导耐药率为25%,开展D试验检测可给临床提供具有参考价值的数据。

Objective To investigate the antimicrobial resistance and inducible resistance of erythromycin and clindamycin in Staphylococcus aureus isolated from food and mess kit in Shenzhen in 2007. Methods The identification and susceptibility test of the isolates was determined by international standard method. VITEK2 Compact and K - B method were used to conduct verification and drug sensitivity respectively. The inducible resistance of erythromycin to clindamycin was checked by D - test. Results Fifty - three S. aureus isolates which were separated from food and mess kit were resistant to penicillin - G, ampicillin, amoxicillin/clavulanic acid in a high level of above 80 %, but sensitive to vancomycin, teicoplanin, meticillin, ampicillin/sulbactam, cefazolin, cefalotin and cefoxitin. Coresistance to erythromycin and clindamycin accounted for 11.3 %. The positive rate of D- test was 11. 3 % among all S. aureus tested. The isolates of inducible resistance rate to clindamycin were 25 % which possessed erythromycin resistant or mesomerism and clindamycin sensitive by individual disk diffusion test. Conclusions Nearly all of the food isolates are MSSA, the antibiotics have high activity to the food isolates except penicillins; the rate of inducible clindamycin resistance is 25 % among erythromycin- resistant or mesomerism, clindamycin - susceptible strains, and D - test can provide the data of reference value to the clinic. resistance