Study And Investigate On Pseudomonas Aeruginosa Drug-resistance Status In Primary Hospital

【Objective】To explore the present situations and levels of the drug resistance of Pseudomonasaeruginosa strains in primary hospital, To identify the classifications ofbeta-lactamase and its relationship with drug resistance of pseudomonas aeruginosa,to expound the role of OprD2gene deletion and the beta-lactamase resistance genecarried on in the resistance beta-lactam antibiotics, to study on the resistantmechanism of beta-lactamase antibiotic to the Pseudomonas aeruginosa, which aresignificant to prevent and control the emergence and dissemination of resistant strainsin primary hospital as well as offer clinics bases to guide primary hospital to chooseappropriate antibiotics reasonably.【Methods】1.Pseudomonas aeruginosa antibiotic susceptibility determination:15kinds ofantibiotics resistance to pseudomonas aeruginosa were detected by VITE-2system.2. β-lactamase in Pseudomonas aeruginosa detected：(1) Extended spectrum-lactamase, AmpC enzyme were detected by improvedthree-dimensional test.(2) Metallo-β-lactamase was detected by disk synergy test.3. Polymerase chain reaction (PCR) technical is utilized to amplify beta-lactamaseand OprD2gene，DNA sequencing was adopted to analyze the resistance-relatedgenes.【Results】1The sensitivity results of90strains of Pseudomonas aeruginosa to the15kinds of antibiotics:higher sensitivity of the six kinds of antibiotics followed by amikacin, meropenem,cefepime, L-ofloxacin, imipenem ceftazidime, whose sensitive rate were75.5%,71.1%,70.0%,67.8%,66.7%,65.6%in turn. The higher antibiotic resistance rates ofPseudomonas aeruginosa, followed by Furadantin, ceftriaxone, cefotaxime,piperacillin,whose resistance rates were95.6%,83.4%,67.8%,48.9%in turn.2. Among90strains of Pseudomonas aeruginosa, the beta-lactamase enzymeproduction rate was27.8%(25/90),25enzyme-producing bacteria producing9metallo-lactamase strains, accounting for36.0%; production7extended-spectrum-lactamasesstrains, accounted for28.0%;6AmpC producing strains, accounting for24.0%;3ESBLs and AmpC enzymes of strains, accounting for12.0%.3The beta-lactamase-producing strains of antimicrobial susceptibility test results:Except Furadantin,the resistance rates of beta-lactamase-producing strains werehigher than non-beta-lactamase-producing strains (P<0.05), The resistant rate of thebeta-lactamase-producing Pseudomonas aeruginosa to beta-lactama antibiotics,quinolones, aminoglycosides were very high.31strains of multidrug resistant(MDRPA) were detected, accounting for34.4%. These strains were mainly distributedin the sputum, accounting for51.7%. Pseudomonas aeruginosa strains were mainlydistributed in ICU and Respiratory Medicine, accounting for40.0%and26.7%. Therate of MDRPA strains was highest in ICU, accounting for54.8%.4.PCR results showed that7strains of ESBLs-producing were positive for OXA-10gene,3strains of MBL-producing were positive for VIM-2gene, OprD2gene wasnegative in16strain, The rest of resistance gene was not detected.【Conclusion】1Susceptibility results showed that the resistant rates of pseuabmonas aeruginosawere very serious and the Mult-drug resistant strains were common in primaryhospital.2Nearly one-third of the primary hospital Pseudomonas aeruginosa strains producebeta-lactamase, beta-lactamase-producing strains resistance was significantly higherthan non-beta-lactamase-producing strains, the resistant rate of the beta-lactamase-producing strains to beta-lactama antibiotics, quinolones, aminoglycosides were veryhigh.3Pseudomonas aeruginosa carrying OXA and-10, VIM-2gene and OprD2gene deletion is may be one of the mechanism for bacteria to beta-lactam antibioticresistance.