新疆动物源葡萄球菌多重耐药基因cfr及其移动元件检测

Detection of multidrug resistance gene cfr and their mobile element of Staphylococci from animals in Xinjiang

从新疆部分地区采集动物源粪样及鼻腔样共计1 781份,从中分离葡萄球菌1 667株,进行临床常用11种抗菌药物的药敏试验,采用PCR方法进行酰胺醇类耐药基因(cfr、fexA和fexB)及与cfr转移相关的移动元件IS21-558和转座酶基因Tn558的检测。结果显示:新疆动物源葡萄球菌对临床常用抗菌药物耐药严重程度为羊源>宠物源>猪源>禽源>牛源,对被检抗菌药物中的青霉素耐药最严重,耐药率为54.7%～93.6%。除牛源菌外(36.3%),其余动物源分离的葡萄球菌对苯唑西林的耐药率为51.1%～98.2%。动物源葡萄球菌对阿米卡星、庆大霉素和克林霉素均有较好的敏感性。多药耐药结果显示,羊源菌以4～5耐为主,禽源菌和宠物源菌以3～5耐为主,猪源菌以4耐和7耐为主,牛源菌以1耐为主,不同动物源分离的葡萄球菌耐药谱型多样化。酰胺醇类耐药基因检测结果显示,仅在猪源菌中检出4株菌携带cfr基因。除牛源菌外,在其余动物源中均检出fexA基因,检出率为宠物源>猪源>禽源>羊源,未检出fexB基因。16SrRNA序列扩增结果显示4株携带cfr基因的阳性菌都为模仿葡萄球菌。此外,在4株阳性菌中都检出移动元件IS21-558(包括:istAS和istBS)和Tn558转座酶基因(tnpA、tnpB、tnpC)。新疆动物源葡萄球菌耐药情况严重,耐药谱型多样化,酰胺醇类耐药基因以携带fexA基因为主。此外,多重耐药基因cfr及其移动元件的检出,提示应加强耐药性的监测,防止耐药菌的暴发和超级耐药菌出现的概率。

In order to understand the clinical antimicrobial resistance of Staphylococci and their multidrug resistance gene cfr from animals in Xinjiang,and to provide guidance for clinical medication and further study of the cfr gene transmission mechanism,a total of 1 781 animal feces and nasal samples were collected from some areas of Xinjiang Uygur Autonomous Region.A total of 1 667 strains of Staphylococci were isolated from the samples,and then drug sensitivity tests of 11 kinds of clinical antibiotics were carried out.The PCR method was used to detect the amide-alcohol resistance genes(cfr,fexA,and fexB),the mobile elements IS 21-558 and transposase gene Tn 558,which were related to the transfer of cfr.The results showed that the order of severity of drug resistance of Staphylococci to clinical commonly used antimicrobial agents was sheep source>pet source>pig source>poultry source>cattle source.The penicillin resistance was the most serious among the tested antibiotics,and the drug resistance rate was between 54.7%and 93.6%.Except for Staphylococci isolated from cattle(36.3%),the resistance rate of Staphylococci isolated from other animals to oxacillin was 51.1%-98.2%.Staphylococcus from animals showed good sensitivity to amikacin,gentamicin and clindamycin.Among the 11 clinical antibiotics,the multidrug resistance rate of Staphylococcus was concentrated in 4-5 from the sheep source,was concentrated in 3-5 from the poultry and pet source,was mainly 4 and 7 from the pig source,and was 1 from the bovine source.Staphylococcus isolated from different animal sources had a wide range of antibiotics resistance spectrum.The detection results of amide-alcohol resistance gene showed that,only 4 strains of Staphylococcus isolated from pigs carried cfr gene.Except for bovine source Staphylococcus,fexA gene was detected in other animal sources with the order of detection rate of pet source>pig source>poultry source>sheep source,but the fexB gene was not detected.The 16S rRNA sequence amplification results showed that the 4 strains carrying the cfr gene were all Staphylococcus simulans.In addition,mobile element IS 21-558(including istAS and istBS)and Tn 558 transposase gene(tnpA,tnpB,tnpC)were detected in 4 positive bacteria.From above,the resistance of Staphylococcus from animal origin was serious in Xinjiang,the spectrum of resistance was diverse,and the main gene of amide-alcohol resistance was the fexA gene.In addition,multidrug resistance gene cfr and its mobile components were detected.It is suggested that the surveillance of drug resistance should be strengthened to prevent the outbreak of drug resistance bacteria and the probable emergence of super resistant bacteria.