Epidemiological And Antibiotic Resistance Related Gene Study On Acinetobacter Baumannii

Objective: To study the epidemiology of Acinetobacter baumanniiinfections and the antibiotic resistant gene related to carbapenemasesresistance in the second affiliated hospital of Chongqing MedicalUniversity.Methods: Microscan was used for Acinetobacter baumannii strainidentification and susceptibility testing. The risk factors of the infection ofmultidrug-resistant Acinetobacter baumannii were assessed bynon-conditional logistic regression analysis. The drug resistant genes weredetected By multiplex Polymerase Chain Reaction (PCR) usingcarbapenemase-specific gene primers.Results:(1) The positive rates of multidrug-resistant Acinetobacterbaumannii from various wards and infection sites were significantlydifferent. The positive rates of multidrug-resistantance from ICU andRespiratory ward was significantly higher than from other wards.(2)Multivariate unconditional logistic regression analysis showed that theindependent risk factors leading to infections of multidrug-resistantAcinetobacter baumannii included: in ICU, using two and over two antibiotics, invasive procedures.(3) The drug susceptibility tests showedthat the resistant rates to common antibiotics of multidrug-resistantAcinetobacter baumannii were remarkable high, most of them were above90%.(4) Of the80multidrug-resistant Acinetobacter baumannii,73stainscarried OXA-51-like（91.3%）,49stains carried OXA-23-like（61.3%）,7stains carried OXA-58-like（8.8%）,1staincarried OXA-24-lik（e1.3%）,17stains carried IMP（21.3%）,2stains carried VIM（2.5%）.Conclusions:(1) There was highly morbidity of Acinetobacterbaumannii infections in our hospital, particularly in ICU and Respiratoryward. Such infections are very difficult to treat due to the widespreadresistance of these bacteria to the major groups of antibiotics.(2) Riskfactors of infection of multidrug-resistant Acinetobacter baumannii wereassociated with ICU, invasive procedures, treatment of antibiotics, soreasonable treatment is very important.(3) The prevalent carbapenemaseresistant genes were OXA-51-like, OXA-23-like and IMP in our hospital.Mechanismof antibiotic resistance possibly closed connected withthis gene.More attention should be paid to such resistantance and its spread in thehospital.