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Objective: To understand Acinetobacter baumannii nosocomial infection status quo, to study the characteristics of Acinetobacter baumannii production of beta-lactamase enzyme analysis of the carbapenem imipenem-resistant strains of the enzyme genotype homology for hospital infection prevention, control and treatment of laboratory evidence. Methods: Bowman fixed bacillus caused by hospital infections infection in 98 patients were retrospectively and analysis of susceptibility with WHONET5.4 software, clear their infection status, drug resistance. Paper with the nitrocefin (by Nitrocefin) chromogenic screening Acinetobacter baumannii production of beta-lactamase, and then three-dimensional test and double-disk synergy experiment of AmpC and extended-spectrum beta-lactamase enzyme (ESBLs) and the detection of metal beta-lactamase (MBLs). Polymerase chain reaction (PCR) detection of imipenem-resistant strains of carbapenemase genotype. Imipenem-resistant Acinetobacter baumannii using pulsed-field gel electrophoresis (PFGE) typing, clustering analysis showed that the genetic relationship. Results: Acinetobacter Acinetobacter infection rate is higher, the ICU ward, orthopedics, neurosurgery most common, accounting for 62.24% of the number of infections, 12.24%, 6.12%; site of infection to the respiratory tract and surgical incision, accounting for 70.41% and 18.37%, respectively. Susceptibility results show that imipenem resistance rate: 64.29% other antibiotics was 65% -90%. 98 Acinetobacter Acinetobacter were detected in 94 of the beta-lactamase positive, the positive rate was 95.92%; 58 AmpC enzyme positive, the positive rate was 59.18%; 9 ESBLs positive, the positive rate was 9.18%; does not detect the MBL. PCR analysis showed that imipenem resistant strains carbapenemase genotype: the blaOXA - 23 genotype 24, blaOXA-58 genotype 3, blaOXA-64-like genotypes 48, blaOXA-20, blaOXA -24, blaOXA-48, blaOXA-50, blaOXA-55, blaOXA-60 genotype test results were negative, is not detected metal enzyme IMP, VIM gene. PFGE results showed that: 63 imipenem-resistant Acinetobacter Acinetobacter divided into A, B, C, D, E five types by PFGE, 46 isolates from the First Affiliated Hospital of Bengbu Medical College is divided into A, B , C three genotypes, A-type main 41 A1 subtype 32, eight subtypes A2, A3 subtype 1, B-3, C-2. Bengbu Central Hospital 17 4 First Affiliated Hospital of Bengbu Medical A1 consistent with the rest: 11 D-type D1 subtype 9, D2 subtype 2, 2 E-type. Conclusion: the Acinetobacter baumannii nosocomial infection rate is higher, and render multi-drug resistant. Producing beta-lactamase in serious condition, is the main reason for resistance to beta-lactam antibiotics. The main mechanisms of resistance to carbapenem antibiotics: production OXA-23, OXA-51-type carbapenemase. The PFGE typing technology results show that the phenomenon of cross-infection between wards, departments and hospitals of the region.
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