head JofIMAB
Journal of IMAB - Annual Proceeding (Scientific Papers)
Publisher: Peytchinski Publishing
ISSN: 1312-773X (Online)
Issue: 2017, vol. 23, issue 4
Subject Area: Medicine
DOI: 10.5272/jimab.2017234.1828
Published online: 18 December 2017

Original article

J of IMAB 2017 Oct-Dec;23(4):1828-1833
Dobromira Dimitrova1ORCID logo, Temenuga Stoeva1ORCID logo Corresponding Autoremail, Rumyana Markovska2ORCID logo, Petya Stankova2ORCID logo, Milena Bozhkova1ORCID logo, Gergana Nedelcheva1ORCID logo, Ivan Mitov2ORCID logo,
1) Department of Microbiology and Virology, Medical University, Varna, Bulgaria.
2) Department of Medical Microbiology, Medical University, Sofia, Bulgaria.

Purpose: Rapidly increasing antimicrobial resistance in medically important bacterial species from family Enterobacteriaceae is one of the most significant microbiological, clinical and epidemiological issues of modern medicine. The aim of this study is to investigate the antibiotic susceptibility of clinically significant isolates of Enterobacter spp., obtained from patients, hospitalized in University Hospital “Saint Marina” – Varna during the period 2014 – 2016.
Material and methods: a total of 433 clinical isolates of Enterobacter spp.from blood cultures, urine and wound secretions were studied. The species identification was made by conventional, semi-automated (Crystal, BD) and automated systems (Phoenix, BD). The susceptibility to piperacillin/tazobactam (TZP), ceftazidime (CAZ), meropenem (MEM), gentamicin (Gm), amikacin (Ak), ciprofloxacin (CIP), levofloxacin (LVX), trimethoprime/sulfamethoxazole (SXT) and tetracycline (Tet) was tested by disc-diffusion method and / or automated system Phoenix 100, BD. The results were interpreted according to EUCAST 2016 guidelines.
Results: The resistance in the studied collection of isolates, shown in increasing order is as follows: Аk, 4.2% <LVF, 25.4% <TZP, 37.4% <Tet, 38.7% <SXT, 40% <CIP, 44.1% <Gm, 49.7% <CAZ, 57%. Meropenem demonstrated fully preserved activity. In the group of CAZ resistant isolates, the levels of antimicrobial resistance are: Аk, 5.7% <LVF, 42.9% <Tеt, 52.4% <SXT, 60.3% <TZP, 64.4% <CIP, 84.6% <Gm, 86.2%. The rate of CAZ resistant Enterobacter spp. was 66.9% among the urine isolates, 61.9% - among those from blood culture and 46.3% - in the group of isolates from wound secretions. In the three mentioned groups of isolates, the lowest level of resistance was detected to Ak (1.6%; 4%; 6.9%). The isolates from wound and blood cultures demonstrated the highest level of resistance to Gm (60.3%, 42.9%) and the urine isolates – to Тet (60%) and CIP (56.9%).
Conclusions: CAZ resistant Enterobacter spp. demonstrated significantly higher levels of resistance in comparison to the whole studied group especially to quinolones and aminoglycosides. The highest level of CAZ resistant Enterobacter spp.  was detected in the group of urine isolates.

Keywords: Enterobacter spp., antimicrobial susceptibility, resistance,

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Please cite this article in PubMed Style or AMA (American Medical Association) Style:
Dimitrova D, Stoeva T, Markovska R, Stankova P, Bozhkova M, Nedelcheva G, Mitov I. Antimicrobial susceptibility of clinically significant isolates of Enterobacter spp., obtained from patients, hospitalised in Varna University Hospital during the period 2014 – 2016. J of IMAB. 2017 Oct-Dec;23(4):1828-1833. DOI: 10.5272/jimab.2017234.1828

Corresponding AutorCorrespondence to: Assoc. Prof. Temenuga Stoeva, MD, PhD, Department of Microbiology and Virology, Medical University, Varna; 55, Marin Drinov Str., Varna, Bulgaria; E-mail: temenuga.stoeva@abv.bg

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Received: 29 August 2017
Published online: 18 December 2017

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