Abstract
BackgroundAcinetobacter baumannii is a nosocomial pathogen which is reported as a major cause of morbidity and mortality in intensive care units (ICUs). However, there is a lack of analysis focused on multidrug-resistant Acinetobacter baumannii (MDRAB) infection among patients from pediatric intensive care unit (PICU) in China. The aim of this study was to investigate the molecular characterization of MDRAB isolated from PICU.MethodsIn this study, 86 isolates of MDRAB were collected from PICU patients, from the First Affiliated Hospital of Sun Yat-sen University. The minimal inhibitory concentrations (MICs) of the isolates against common antibiotics were determined. The carbapenemase-encoding resistance genes and AdeABC-AdeRS efflux system genes of these isolates were detected by PCR. Real-time PCR was performed to determine the relative expression of the relevant efflux pumps.ResultsAmong 86 strains of MDRAB, 76.7% (66/86) were carbapenem-resistant A. baumannii (CRAB). All 86 clinical isolates possessed the blaOXA-51 gene. BlaOXA-23 was detected as the second most frequent (90.7%) carbapenemase. Harboring AdeABC efflux pump genes was prevalent among the majority of the MDR isolates. Specially, the distributions of AdeABC-AdeRS efflux system genes in CRAB strains reached up to 90.0%. Compared with those of the CSAB strains, there was a statistically significant increasing distribution of the regulator AdeR and AdeS genes(p < 0.05). Moreover, CRAB strains showed significantly increased expression of AdeB(12.3- fold), but decreased expression of AdeR (3.3- fold)(p < 0.05).ConclusionThe present study showed a high distribution of multiple genes, mainly the genes of blaOXA-23/blaOXA-51 carbapenemase and AdeABC efflux pump, is responsible to distinct drug-resistance in PICU. It is urgent to strengthen the molecular epidemiological surveillance of pediatric MDRAB isolates to prevent further outbreaks. This study is of significant help for the clinicians to make therapeutic decisions and manage infection control in PICU.
Highlights
Acinetobacter baumannii is a nosocomial pathogen which is reported as a major cause of morbidity and mortality in intensive care units (ICUs)
The distributions of AdeABC-AdeRS efflux system genes among carbapenem-resistant A. baumannii (CRAB) strains were more than 90.0%, and compared with the carbapenem -susceptible A. baumannii (CSAB) strains, there was a statistically significant increasing distribution of the regulator AdeR and AdeS genes(p < 0.05)
There was a higher distribution of co-harboring AdeABC-AdeRS efflux system genes and blaOXA-23 among the CRAB strains (Table 4)
Summary
Acinetobacter baumannii is a nosocomial pathogen which is reported as a major cause of morbidity and mortality in intensive care units (ICUs). There is a lack of analysis focused on multidrug-resistant Acinetobacter baumannii (MDRAB) infection among patients from pediatric intensive care unit (PICU) in China. Acinetobacter baumannii has been reported as an epidemiologically and clinically life-threatening nosocomial pathogen causing critical morbidity and mortality, especially in intensive care units (ICUs) [1]. It is extensively reported that carbapenem resistant strains of Acinetobacter baumannii (CRAB) have caused the hospital outbreaks worldwide [2,3,4]. To increase awareness and improvement of epidemiological surveillance is a significant and critical factor of successful infection control and is recommended in ICUs. To our knowledge, few studies on the molecular characterization of MDRAB isolated from PICU are reported in China. The present study was conducted to determine the molecular characteristics among the MDRAB strains from PICU in a tertiary hospital in Guangzhou, China, during a 5-year period from January 2013
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
