Determination of antibiotic resistance pattern and frequency of blaVIM & blaIMP genes in clinical isolates of Acinetobacter species in Bandar Abbass

Subject Areas : Medical Microbiology

Fahime Golestani ¹ , Sedigheh Javadpour ² , Farshid Kafilzadeh ³ , Zeinab Ghalandarzadeh Daryaei ⁴

1 - M.Sc., Department of Microbiology, Jahrom branch, Islamic Azad University, Jahrom, Iran.
2 - Associate Professor, Molecular Medicine Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas, Iran.
3 - Professor, Department of Microbiology, Jahrom branch, Islamic Azad University, Jahrom, Iran.
4 - M.Sc., Department of Microbiology, Jahrom branch, Islamic Azad University, Jahrom, Iran.

Received: 2016-12-08 Accepted : 2017-01-24 Published : 2018-02-20

Keywords: Acinetobacter baumannii, Imipenem, Metalobetalactamase, Meropenem, blaIMP gene, blaVIM gene,

Abstract :

Background & Objectives: Acinetobacter spp. are non-fermenting Gram-negative bacteria that are associated with nosocomial infections. They are serious opportunistic pathogens with resistance to many antibiotics due to the presence of Metallo-beta-lactamase (MBL) genes. The aims of this study were to determine antimicrobial susceptibility and frequency of MBLs genes in clinical isolates of Acinetobacter species in Shahid Mohammadi hospital, Bandar Abbas, Iran. Material & Methods: This descriptive- cross-sectional study was carried out on 81 Acinetobacter isolates collected from different clinical samples from Shahid Mohammadi hospital, Bandar Abbas, Iran. The bacteria were identified to the species level by Microgen GNA-ID System kit. The Kirby-Bauer disk diffusion test was used to determine antibiotic resistance pattern. MIC of meropenem was determined by E-test, and MBLs production was detected by imipenem-EDTA synergy test (CDST method). The isolates were then subjected to polymerase chain reaction (PCR) for detection of blaIMP and blaVIM genes. Results: Out of 81 isolates, 79(97.54%) were identified as A. baumanni, 1 (1.23%) as  A. lwoffii and 1(1.23%) as A. haemolyticus. Acinetobacter spp. showed the highest resistance to imipenem and meropenem (81.5%) and the highest susceptibility to polymyxin B (96.3%) and colistin(95.1%), respectively. MIC determination by E-test revealed 77.8% of isolates as meropenem- resistant.76.5% of isolates were identified as MBL- positive by CDST method. Also, 13 (16%) isolates carried blaIMP gene, but none of them had the blaVIM gene. Conclusion: Dissemination of MBL- producing A. baumannii is worrisome. In order to reduce and control Acinetobacter infections, implementation of strict surveillance, and judicious prescribing of antibiotics is necessary.