title: Study on the resistant genes to carbapenems and epidemiological characterization of multidrug-resistant Acinetobacter baumannii isolates.
abstract: The purpose of this study was to examine the carbapenemase-encoding resistance genes and analyze homologous of multidrug-resistant Acinetobacter baumannii (MRAB) isolates from nosocomial infections. Seventy-six A. baumannii strains were collected from inpatients and object surface of devices in intensive care units from May 2008 to February 2011. Antibiotic susceptibility testing of 18 antimicrobial agents was performed. The presence of carbapenemase-encoding resistance genes was investigated by polymerase chain reaction. Genotyping and dendrogram analysis of A. baumannii strains from nosocomial infections were performed using the DiversiLab System. All of the 76 clinical A. baumannii isolates were shown multidrug resistance. The bla(OXA-23) gene was identified in the 76 MRAB strains, while bla(OXA-24), bla(OXA-58), VIM, IMP-1, IMP-4, SIM, and blaNDM-1 were absent in all. Twenty-four A. baumannii strains from the samples with nosocomial infections were classified into four unrelated groups and nine patterns. In conclusion, production of bla(OXA-23) in MRAB is one of the molecular mechanisms responsible for carbapenem resistance. The MRAB strains from unrelated groups show different drug resistance, but the homologous strains also have different drug resistance. Homologous analysis can provide scientific evidence for evaluation of epidemic status of nosocomial infection caused by MRAB.
authors: Laboratory Medicine Department, Sichuan Academy of Medical Sciences, Sichuan Provincial People's Hospital, Chengdu, China.
authors: Wei
authors: W
authors: Jiang
authors: Hua
authors: H
authors: Liu
authors: Min
authors: M
authors: Zhong
authors: Yong Chang
authors: YC
authors: Yang
authors: Dai Wen
authors: DW
authors: Xiao
authors: Wen Fang
authors: WF
authors: Huang
mesh_terms: D000151:Acinetobacter Infections / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000145:classification / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015373:Bacterial Typing Techniques; D015780:Carbapenems / Q000494:pharmacology*; D002681:China / Q000453:epidemiology; D003428:Cross Infection / Q000188:drug therapy / Q000453:epidemiology* / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D004865:Equipment and Supplies, Hospital / Q000382:microbiology; D006801:Humans; D007362:Intensive Care Units; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction; D018440:beta-Lactam Resistance / Q000187:drug effects / Q000235:genetics*; D001618:beta-Lactamases / Q000145:classification / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D001618:beta-Lactamases