Genotyping Analysis Of Aminoglycoside Modifying Enzyme In Multiple Drug Resistance Pseudomonas Aeruginosa Clinical Isolates In Baoding Distract

Objective:1 To understand the conditions of Antibiotic resistant Pseudomonas aeruginosa(P.aeruginosa)in clinical samples from Baoding district.2 To analyze the distribution of Aminoglycoside resistance genes in these multidrug resistant P.aeruginosa that will provide the instructions for the application of antibiotics.Based on these understanding,we can reduce the generation of drug resistant bacteria,and effectively prevent and control ward infection.Methods:1 The source of bacterial strain: According to instruction of The Ministry of Public Health National Guide to Clinical Laboratory Procedures(Third Edition),we isolated and cultured of bacteria from clinical samples,and used VITEK-2 automatic microbe instrument to identify bacteria species.2 Antimicrobial susceptibility tests: One hundred and fourty-two clinical P.aeruginosa isolates have been collected from Baoding first center hospital from January to August in 2016.All of them were identified by automatic microbe instrument VITEK-2.Their antibiotic sensitivity to 20 kinds of clinical drugs was detected by K-B method.3 Detection the expression of drug resistant gene: Six kinds of aminoglycoside resistance genes(aac(3)-Ⅰ,aac(3)-Ⅱ,aac(6′)-Ⅰb,aac(6′)-Ⅱ,ant(3″)-Ⅰ 、 ant(2″)-Ⅰ)were detected by PCR amplification in 32 multidrug resistant P.aeruginosa isolated from clinical samples which were collected from July to August 2016.Results:1 The antibiotic sensitivity to 20 kinds of drugs was detected in 142 P.aeruginosa isolated from clinical samples.In this study,the ranking for these antibiotics with high resistance was shown as following: cefazolin(97.1%),ceftriaxone(95.7%),cefuroxime ester(95.7%),cefuroxime sodium(95.1%),ampicillin(95.0%),ampicillin/sulbacta(94.3%),cefotetan(94.3%),cotrimoxazole(92.9%),and cefoperazone(54.2%).In contrast,antibiotics with high sensitivity were amikacin respectively(78.1%),tobramycin(71.1%),piperacillin and tazobactam(64.0%),ceftazidime(61.95%),piperacillin(56.3%),meropenem(56.3%),levofloxacin(53.5%),ciprofloxacin(52.8%),gentamicin(44.3%),and imipenem(47.1%).2 Aminoglycoside resistant genes were detected in 32 multiple drug resistant P.aeruginosa isolated from clinical samples.Among them,aac(3)-Ⅱ,aac(6’)-Ⅰb,and ant(3″)-Ⅰwere positive,with the positive rate as 12.5%,18.7% and 9.3% respectively.However,other genes,aac(3)-Ⅰ,aac(6’)-Ⅱ,and ant(2")-Ⅰwere undetectable.Conclusions:1 In our study,we found that P.aeruginosa isolated from clinical samples in Baoding first center hospital showed great resistance to 8 kinds of antibiotics,including cefazolin,ceftriaxone,cefuroxime ester,cefuroxime sodium,ampicillin,ampicillin/sulbacta,cefotetan,and cotrimoxazole.2 P.aeruginosa isolated from clinical samples in our hospital showed great sensitivity to amikacin,tobramycin and gentamicin,indicating that these antibiotics should be firstly considered for clinical application.3 In our study,multidrug resistant P.aeruginosa were identified carrying the aminoglycoside resistance genes of aac(3)-Ⅱ(4,12.5%),aac(6’)-Ⅰb(6,18.7%),ant(3″)-Ⅰ(3,9.3%),with negative expression for aac(3)-Ⅰ,aac(6’)-Ⅱ,and ant(2")-Ⅰ genes,suggesting the relationship between aminoglycoside resistance genes and the high rate of multidrug resistant P.aeruginosa.4 Take together,it is necessary to strengthen the monitor the drug resistant status of P.aeruginosa and related gene expression,guiding more effective application of antibiotics.