Detection of drug resistance and OXA genotypes in Acinetobacter baumannii isolated from patients of burn units

Lv Dalun; Chen Lei; Ding Wei; Xu Shujuan; Zhang Wei; Wang Heli; Wang Shuai

doi:10.3969/j.issn.1672-8521.2016.04.004

Abstract：Objective: To investigate the drug resistance and OXA gene carrying case of Acinetobacter baumannii isolated from burn patients to provide a basis for prevention and control of hospital infection induced by multi-drug resistant Acinetobacter baumannii.Methods: Bacterial culture of wound secretion was performed in 2572 burn patients admitted to the Burns and Plastic Surgery of the First Affiliated Hospital of Wannan Medical College from January 2013 to February 2015. VITEK 2 Compact automatic microbial detection system was used to identify Acinetobacter baumanii, and its susceptibility to 18 kinds of antimicrobial were tested. Four kinds of OXA carbapenemase genes (OXA-23-like, OXA-24-like, OXA-51-like, OXA-58-like) in Acinetobacter baumannii were detected by polymerase chain reaction, and OXA-23-like gene was sequenced in 10 strains.Results: Totally 44 strains of Acinetobacter baumannii were isolated, and the resistance rate to imipenem was 79.55% ( 27 strains), they were lower to Minocyline and tigecycline (20.45%, 9 strains and 31.82%,14 strains respectively) , but high (100%) to gentamicin, and maintained at higher resistance rate to other antibiotics (59.09%-97.73%). In all strains of Acinetobacter baumannii, the OXA-51-like genes were positive, and a total of 35 OXA-23-like genes-positive strains (79.55%) were detected, while no OXA-24-like gene and OXA-58-like gene positive strains were found.Conclusions:Acinetobacter baumannii showed multiple drug resistance, the resistance rate to minocycline is low. The mechanism of multi-drug resistance of Acinetobacter baumannii in our hospital may be related mainly to OXA-23-like genes.