Surveillance And Analysis Of Acinetobacter Baumannii Isolated From Intensive Care Unit In A Tertiary Hospital

Objective The drug resistance and homology analysis of Acinetobacter baumannii(AB)isolated from ICU.Combined with the drug resistance and homology results,it provides a basis for rational use of antibiotics and prevention and control of the spread of AB in clinic.Method The drug resistance of AB strains isolated from clinical specimens of patients with nosocomial infection in the ICU of the People's Hospital of Inner Mongolia Autonomous Region from 2016 to 2018 was analyzed retrospectively.The clinical data of patients with nosocomial infection in AB were collected and divided into MDR-AB group and non-MDR-AB group.SPSS22.0 statistical software was used to analyze the data of the two groups of patients,screening out the related risk factors of MDR-AB infection,and then introducing these factors into binomial logistic regression equation for multivariate analysis.Finally,the independent risk factors of MDR-AB infection were determined.The homology analysis of pulsed field gel electrophoresis(PFGE)was performed on 24 clinical specimens and environmental samples collected from 1-5 months in 2018.Result 1.From 2016 to 2018,the detection rate of AB in G-bacteria ranked the first,and the distribution of the main pathogenic bacteria in each year was different and had statistical significance(P(27)0.05).2.From 2016 to 2018,the incidence of nosocomial infection in ICU has increased year by year(P(27)0.05),while the incidence of nosocomial infection in AB had no statistical significance(P(29)0.05).Among all sputum samples,AB had the highest detection rate,43.88%,40.00% and 40.19% respectively.From 2016 to 2018,the detection rate and the proportion of AB samples per year were not statistically significant after Chi-square test(P(29)0.05).3.Drug susceptibility test showed that the resistance rate of AB to levofloxacin was lower than that of other antibiotics,and the resistance rate of AB to other antibiotics was above 74%.The resistance rates to piperacillin,ampicillin,cefuroxime,cefazolin,ceftitam and furantoin were 100%.However,the three-year drug resistance rates of to bramycin,gentamicin,levofloxacin and compound neotamine were significantly different(P(27)0.05).4.The results of single factor analysis showed that there were significant differences between MDR-AB group and non-MDR-AB group in respiratory diseases,fungal infections,mechanical ventilation,arteriovenous catheterization and combined use of antibiotics(P(27)0.05).In multivariate logistic regression analysis,fungal infection,arteriovenous intubation and combined use of antibiotics were independent risk factors for MDR-AB infection.5.From January to May 2018,17 strains of MDR-AB were collected and preserved from patients with nosocomial infection in ICU,and the detection rate was 76.92%.Seven strains of MDR-AB were isolated from 43 environmental samples collected from wards,with a total detection rate of 16.28%.The similarity of 24 MDR-AB strains was between 36.94% and 100% after PFGE typing,whether from the genome of patient samples or the genome of strains in ward environment.UPGMA cluster analysis based on 74% similarity coefficient yielded 9 clusters(A-I).Most of them are G-clustering,including G1,G2 and G3 clones.Conclusion From 2016 to 2018,AB accounted for the largest proportion of pathogenic bacteria is isolated from ICU in the hospital,and the incidence of nosocomial infection of AB is not change significantly.Among all the specimens isolated from AB,sputum specimens is accounted for the highest proportion.AB has more multidrug-resistant bacteria and is less sensitive to commonly used clinical antibiotics.The combination of fungal infection,arteriovenous catheterization and antimicrobial use are independent risk factors for MDR-AB infection.Through the analysis of PFGE typing of MDR-AB,it is found that the spread of clones in hospitals has become an important problem of nosocomial infection and an important factor for the increase of drug-resistant strains.Therefore,the management of nosocomial infection should be strengthened and use of antibiotics rational to prevent the outbreak of MDR-AB.