Drug Resistant Mechanism And Molecular Epidemiology Of Multiple Drug Resistant Pseudomonas Aeruginosa In Burn Patients Secretion

Objective:The study was conducted to research multi-drug resistant Pseudomonas aeruginosa resistant to commonly used antibiotics, to find multi-drug resistance of resistant genes and to research the lack of outer membrane protein of excretion of burn patients. By those methods, To analysis of multip-drug resistance of pseudomonas aeruginosa molecular epidemiological characteristics of nosocomial infection. To guide the clinician to effectively control the spread of drug resistant strains and to guide drug using at clinical.Methods:A total of 38 MDRPA of excretion of burn patients were isolated from 1st 2015 in the Second Affiliated Hospital of Kunming Medical University. Using VITEK-2 Compact to identificate strains, MIC method to test drug susceptibility phenotypic, and PCR method to detect outer membrane protein OprD gene, metalloenzyme, such as IMP, SPM, VIM; AmpC genes such as ACT-1、CMY-2; A or D β-lactamase genes, such as CTX-M-3、SHV、KPC、IMI、GES、OXA-48, All amplification results were to analysis sequence. At the same time, Using PCR method to detect seven housekeeping genes, and confirm MLST.Results:The Second affiliated hospital of KunMing Medical University grade a Class-three Hospital. A total of 38 MDRPA of excretion of burn patients were isolated from January 2014 to June 2015 in the Second Affiliated Hospital of Kunming Medical University. basing on CLSI(S23) to explain MIC test of MDRPA, our results show 38 MDRPA isolated from secretion specimen of burn ward resistance to 8 kinds of antimicrobial agents is very severe, performancing multi drug resistance, and even pan drug resistance.38 strains were resistant to one of carbopenems imipenem and meropenem, resistant rate of Meropenem is 89.4%, and Imipenem is 86.8%. in other β-lactam Antibiotics, resistant rate of Ceftazidime is 94.7%. sensitive rate of Piperacillin-tazobactam is 100%. Most strains performance drug resistance to Aztreonam in MIC test, resistant rate is 94.7%. Tigecycline and Amikacin performance strong antibacterial activity in vitro. Most strains performance sensitive to Amikacin, and completely sensitive to Tigecycline.38 strains detected CMY and SHV drug resistance gene by PCR method. Caused multiple drug resistance of genes, such as (3-lactam, Amino glycosides, Fluoroquinolones genes VIM.SPM, ACT-1, CTX-M-3、IMI、GES、OXA-4、aac(6’)-18 were not detected, especially causing carbapenem antibiotic gene such as IMP, KPC which high detection rate in china were not decteted. At the same time outer membrane protein were detected, it explain that outer membrane proteins were transcriped. All positive productions were sequenced. Sequence results show it is peak, no set peak, without interruption, and no attenuation, using BLASTN soft to compared results, positive productions genes types is CMY-2、SHV-2a、OprD-2, seven housekeeping genes aroE、nuoD、ppsA、mutL、acsA、trpE、guaA show positive, and using DNAstar soft to site for comparison after conversion. ST292 type accounted 76.3%, ST244 15.8%and ST9617.9%.Conclusion:MDRPA isolated from secretion specimen of bum ward show multiple drug resistance to carbapenems. quinolones, cephalosporins and penicillin, it is also expression CMY-2, SHV-2a and OprD2 genes. In our study, three ST type were found, Which ST292 has accounted 76.3%and ST244 accounted 15.8%and ST9617.9%, indicates the clone way in which Pseudomonas aeruginosa is transmitted in the bum ward. So, infection caused by MDRPA at bum ward should pay attention, prevention and treatment to prevent the infection spreading.