金黄色葡萄球菌分离鉴定及耐药性分析

Isolation,Identification and Resistance Analysis of Staphylococcus aureus

本试验对河南省南阳某鸡场病死鸡肝脏分离出的疑似金黄色葡萄球菌进行分离鉴定,并对鸡源金黄色葡萄球菌的耐药情况进行分析。用微量肉汤稀释法测定分离菌对11种抗菌药物的敏感性,利用PCR扩增对分离菌进行氨基糖苷类耐药基因aphA、acc(6')-aph(2″)和ant(4')-Ia,大环内酯类耐药基因ermA、ermB和ermC及四环素类耐药基因tetK和tetM的检测。结果表明,分离鉴定出15株金黄色葡萄球菌,这些菌株除对替加环素、万古霉素敏感率为100%外,对其他抗生素药物均呈现不同程度的耐药,其中青霉素、红霉素的耐药率达100%。有66.7%菌株呈现多重耐药性,分离菌株最少耐2种药物,最多耐9种药物。耐药基因检测结果显示,ermC检出率达80%,tetK检出率20%,其余在50%左右。本研究显示,该鸡场分离菌耐药性比较严重,因此,临床应加强耐药性及耐药基因的检测。

In this experiment,the strain were isolated and identified from clinical samples which were collected from the chicken farm in Nanyang City of Henan Province,and the resistance of Staphylococcus aureus from chickens was analyzed.The sensitivity of the isolated bacteria to 11 antimicrobial agents was determined by the microdilution broth method,the related resistance genes such as aminoglycoside modifying enzyme genes(aphA,acc(6')-aph(2″),ant(4')-Ia),erythromycin ribosomal methylase genes(ermA,ermB,ermC)and tetracycline-resistant genes(tetK,tetM)were detected by PCR.The results showed that 15 S.aureus strains were identified,the resistance rates to penicillin and erythromycin were 100%,and the tested strains were susceptible to both tigecycline and vancomycin with the susceptibility rate 100%.Also,66.7%of the strains were multi-resistant,the resistances varied from 2 to 9 kinds of the above drugs.The 80%of the isolates harbored ermC gene,20%harbored tetK gene,and the rest was about 50%.This research shows that antimicrobial resistance of S.aureus is relatively serious.Therefore it is neces⁃sary that drug resistance and resistance gene should be enhancement of monitoring.