Emergence and characterization of nosocomial multidrug-resistant and extensively drug-resistant Acinetobacter baumannii isolates in Tehran, Iran

Bahare Salehi; Hossein Goudarzi; Bahram Nikmanesh; Hamidreza Houri; Mostafa Alavi-Moghaddam; Zohreh Ghalavand

doi:10.1016/j.jiac.2018.02.009

Emergence and characterization of nosocomial multidrug-resistant and extensively drug-resistant Acinetobacter baumannii isolates in Tehran, Iran

J Infect Chemother. 2018 Jul;24(7):515-523. doi: 10.1016/j.jiac.2018.02.009. Epub 2018 Mar 16.

Authors

Bahare Salehi¹, Hossein Goudarzi¹, Bahram Nikmanesh², Hamidreza Houri¹, Mostafa Alavi-Moghaddam³, Zohreh Ghalavand⁴

Affiliations

¹ Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
² Department of Medical Laboratory Sciences, School of Allied Medical Sciences, Tehran University of Medical Sciences, Tehran, Iran.
³ Imam Hossein Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
⁴ Department of Microbiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Electronic address: zghalavand@gmail.com.

PMID: 29555392
DOI: 10.1016/j.jiac.2018.02.009

Abstract

Rationale: Acinetobacter baumannii is one of the antibiotic-resistant superbugs that threatens hospitalized patients. Emergence and spread of the multidrug-resistant (MDR) and extensively drug-resistant (XDR) clones cause erratic outbreaks following environmental contamination of hospital settings.

Objective: The present study intended to characterize the antimicrobial resistant profiles and the genotypes of clinical and environmental isolates of A. baumannii as a result of dissemination of resistant strains.

Methods: Clinical and environmental isolates of A. baumannii were obtained from patients, staff, and environment of an educational hospital in Tehran. Antimicrobial susceptibility testing was carried out using the disk diffusion and E-test methods. Multiplex PCR was performed for detection of OXA-type genes (bla_OXA-23-like, bla_OXA-24-like, bla_OXA-58-like, and bla_OXA-51-like). Genotypic relatedness of the isolates was achieved using repetitive extragenic palindromic element PCR (Rep-PCR) technique.

Results: All the isolates were found to be susceptible to colistin and most of them (77%) were non-susceptible to tigecycline. A majority of the clinical and environmental isolates (97%) were considered as MDR strains and 41% as XDR. In multiplex detection, bla_OXA-23-like was found in 54% of the isolates, which was the most frequent OXA-type gene. In addition, the frequency of the carbapenem-resistant A. baumannii (CRAB) was observed to be high (96%). In addition, molecular typing showed different Rep patterns of clinical isolates and clonal spread of environmental isolates.

Conclusion: The present study highlights the circulation of drug-resistant A. baumannii strains in different wards of hospitals principally in intensive care unit (ICU) as a nosocomial pathogen due to unwise managements.

Keywords: Acinetobacter baumannii; Carbapenem-resistant A. baumannii; Environmental; Extensively drug-resistant; Multidrug-resistant; Nosocomial infection.

MeSH terms

Acinetobacter Infections / epidemiology
Acinetobacter Infections / microbiology*
Acinetobacter baumannii / drug effects*
Acinetobacter baumannii / genetics
Acinetobacter baumannii / isolation & purification
Anti-Bacterial Agents / therapeutic use
Carbapenems / therapeutic use
Colistin / therapeutic use
Communicable Diseases, Emerging / epidemiology
Communicable Diseases, Emerging / microbiology*
Cross Infection / epidemiology
Cross Infection / microbiology*
Cross-Sectional Studies
Drug Resistance, Multiple, Bacterial* / genetics
Genotype
Hospitals, Teaching
Humans
Intensive Care Units
Iran / epidemiology
Minocycline / analogs & derivatives
Minocycline / therapeutic use
Molecular Typing
Tigecycline

Substances

Anti-Bacterial Agents
Carbapenems
Tigecycline
Minocycline
Colistin