Detection of carbapenem resistance and virulence genes among Acinetobacter baumannii isolated from hospital environments in center of Iran

Mohsen Nazari, Zohreh Youzbashi, Mansoor Khaledi, Javad Fathi, Hamed Afkhami


Carbapenem-resistant Acinetobacter baumannii are the top urgent antibiotic resistance threat in the world. The aims of this study were the determination of carbapenem-resistant genes and virulence genes among isolates from hospital environments. In this study, A. baumannii isolated from hospital environments and evaluated its antibiotic resistance, virulence factors, and resistance genes. Of 258 samples, 58 showed growth of the target organism. Antibiotic susceptibility test results considered all the A. baumannii to be multidrug-resistant isolates with the highest resistance being 36.2% to ciprofloxacin; while the most effective antibiotics with 98.3% susceptibility was piperacillin-tazobactam. Of these 58 hospital environment isolates, 18 isolates were positive for Metallo beta-lactamase. Overall, 65% of the isolates from hospital environments had many virulence factors. PCR assays demonstrated the highest and lowest positive results in csgA and cvaC gene among hospital environment isolates. Results indicate that the determination of carbapenem-resistant genes and virulence genes among isolates from hospital environments is very important.


Carbapenem resistance; Virulence gene; Non-clinical isolates; Acinetobacter baumannii


Hashemi B, Afkhami H, Khaledi M, Kiani M, Bialvaei AZ, Fathi J, et al. Frequency of Metalo beta Lactamase genes, bla IMP1, INT 1 in Acinetobacter baumanii isolated from burn patients North of Iran. Gene Rep. 2020; 21:100800.

Howard A, O'Donoghue M, Feeney A, Sleator RD. Acinetobacter baumannii: an emerging opportunistic pathogen. Virulence. 2012; 3(3):243-50.

Khaledi M, Shahini Shams Abadi M, Validi M, Zamanzad B, Vafapour R, Gholipour A. Phenotypic and genotypic detection of metallo-β-lactamases in A. baumanii isolates obtained from clinical samples in Shahrekord, southwest Iran. BMC Res Notes. 2019; 12(1):597.

Malekzadegan Y, Abdi A, Heidari H, Moradi M, Rastegar E, Sedigh Ebrahim-Saraie H. In vitro activities of colistin, imipenem and ceftazidime against drug-resistant Pseudomonas aeruginosa and Acinetobacter baumannii isolates in the south of Iran. BMC Res Notes. 2019; 12(1):301.

Patel SJ, Oliveira AP, Zhou JJ, Alba L, Furuya EY, Weisenberg SA, et al. Risk factors and outcomes of infections caused by extremely drug-resistant gram-negative bacilli in patients hospitalized in intensive care units. Am J Infect Control. 2014; 42(6):626-31.

Basatian-Tashkan B, Niakan M, Khaledi M, Afkhami H, Sameni F, Bakhti S, et al. Antibiotic resistance assessment of Acinetobacter baumannii isolates from Tehran hospitals due to the presence of efflux pumps encoding genes (adeA and adeS genes) by molecular method. BMC Res Notes. 2020; 13(1):543.

Khaledi M, Asadi-Samani M, Mahmoodi-Kouhi A, Gholipour A. Antibacterial effect of the hydroalcoholic extracts of four Iranian medicinal plants on Staphylococcus aureus and Acinetobacter baumanii. Int J Pharm Phytopharm Res. 2017; 7(2):10-4.

Rit K, Saha R. Multidrug-resistant acinetobacter infection and their susceptibility patterns in a tertiary care hospital. Niger Med J. 2012; 53(3):126-8.

Vijayakumar S, Rajenderan S, Laishram S, Anandan S, Balaji V, Biswas I. Biofilm Formation and Motility Depend on the Nature of the Acinetobacter baumannii Clinical Isolates. Front Public Health. 2016; 4:105.

Almasaudi SB. Acinetobacter spp. as nosocomial pathogens: Epidemiology and resistance features. Saudi J Biol Sci. 2018; 25(3):586-96.

Eveillard M, Kempf M, Belmonte O, Pailhoriès H, Joly-Guillou ML. Reservoirs of Acinetobacter baumannii outside the hospital and potential involvement in emerging human community-acquired infections. Int J Infect Dis. 2013; 17(10):e802-5.

Lee CR, Lee JH, Park M, Park KS, Bae IK, Kim YB, et al. Biology of Acinetobacter baumannii: Pathogenesis, Antibiotic Resistance Mechanisms, and Prospective Treatment Options. Front Cell Infect Microbiol. 2017; 7:55.

Go ES, Urban C, Burns J, Kreiswirth B, Eisner W, Mariano N, et al. Clinical and molecular epidemiology of acinetobacter infections sensitive only to polymyxin B and sulbactam. Lancet. 1994; 344(8933):1329-32.

Li J, Rayner CR, Nation RL, Owen RJ, Spelman D, Tan KE, et al. Heteroresistance to colistin in multidrug-resistant Acinetobacter baumannii. Antimicrob Agents Chemother. 2006; 50(9):2946-50.

Olaitan AO, Berrazeg M, Fagade OE, Adelowo OO, Alli JA, Rolain JM. Emergence of multidrug-resistant Acinetobacter baumannii producing OXA-23 carbapenemase, Nigeria. Int J Infect Dis. 2013; 17(6):e469-70.

Hsu LY, Apisarnthanarak A, Khan E, Suwantarat N, Ghafur A, Tambyah PA. Carbapenem-Resistant Acinetobacter baumannii and Enterobacteriaceae in South and Southeast Asia. Clin Microbiol Rev. 2017; 30(1):1-22.

Jeon JH, Lee JH, Lee JJ, Park KS, Karim AM, Lee CR, et al. Structural basis for carbapenem-hydrolyzing mechanisms of carbapenemases conferring antibiotic resistance. Int J Mol Sci. 2015; 16(5):9654-92.

Eijkelkamp BA, Stroeher UH, Hassan KA, Paulsen IT, Brown MH. Comparative analysis of surface-exposed virulence factors of Acinetobacter baumannii. BMC Genomics. 2014; 15(1):1020.

Eraç B, Yılmaz FF, Hoşgör Limoncu M, Oztürk I, Aydemir S. [Investigation of the virulence factors of multidrug-resistant Acinetobacter baumannii isolates]. Mikrobiyol Bul. 2014; 48(1):70-81.

Safari M, Mozaffari Nejad AS, Bahador A, Jafari R, Alikhani MY. Prevalence of ESBL and MBL encoding genes in Acinetobacter baumannii strains isolated from patients of intensive care units (ICU). Saudi J Biol Sci. 2015; 22(4):424-9.

Fallah F, Hakemi Vala M, Goudarzi H, Hashemi A, Taherpour A, Bigdel Shamloo K. Identification of extended-spectrumbeta-lactamases (ESBLs), metallo-betalactamases (MBLs), Amp-C and KPC ßlactamases among Klebsiella pneumoniae isolated from adults and pediatric patients in Iran. Afr J Microbiol Res. 2013; 7


Gräser Y, Klare I, Halle E, Gantenberg R, Buchholz P, Jacobi HD, et al. Epidemiological study of an Acinetobacter baumannii outbreak by using polymerase chain reaction fingerprinting. J Clin Microbiol. 1993; 31(9):2417-20.

El-Shazly S, Dashti A, Vali L, Bolaris M, Ibrahim AS. Molecular epidemiology and characterization of multiple drug-resistant (MDR) clinical isolates of Acinetobacter baumannii. Int J Infect Dis. 2015; 41:42-9.

Higgins PG, Lehmann M, Wisplinghoff H, Seifert H. gyrB multiplex PCR to differentiate between Acinetobacter calcoaceticus and Acinetobacter genomic species 3. J Clin Microbiol. 2010; 48(12):4592-4.

Hujer KM, Hujer AM, Hulten EA, Bajaksouzian S, Adams JM, Donskey CJ, et al. Analysis of antibiotic resistance genes in multidrug-resistant Acinetobacter sp. isolates from military and civilian patients treated at the Walter Reed Army Medical Center. Antimicrob Agents Chemother. 2006; 50(12):4114-23.

Srinivasan VB, Rajamohan G, Pancholi P, Stevenson K, Tadesse D, Patchanee P, et al. Genetic relatedness and molecular characterization of multidrug resistant Acinetobacter baumannii isolated in central Ohio, USA. Ann Clin Microbiol Antimicrob. 2009; 8:21.

Turton JF, Woodford N, Glover J, Yarde S, Kaufmann ME, Pitt TL. Identification of Acinetobacter baumannii by detection of the blaOXA-51-like carbapenemase gene intrinsic to this species. J Clin Microbiol. 2006; 44(8):2974-6.

Darvishi M. Virulence factors profile and antimicrobial resistance of Acinetobacter baumannii strains isolated from various infections recovered from immunosuppressive patients. Biomed Pharmacol J. 2016; 9(3):1057-62.

Jahangiri S, Malekzadegan Y, Motamedifar M, Hadi N. Virulence genes profile and biofilm formation ability of Acinetobacter baumannii strains isolated from inpatients of a tertiary care hospital in southwest of Iran. Gene Rep. 2019; 17:100481.

Nowak P, Paluchowska PM, Budak A. Co-occurrence of carbapenem and aminoglycoside resistance genes among multidrug-resistant clinical isolates of Acinetobacter baumannii from Cracow, Poland. Med Sci Monit Basic Res. 2014; 20:9-14.

Choi WS, Kim SH, Jeon EG, Son MH, Yoon YK, Kim JY, et al. Nosocomial outbreak of carbapenem-resistant Acinetobacter baumannii in intensive care units and successful outbreak control program. J Korean Med Sci. 2010; 25(7):999-1004.

Poirel L, Bonnin RA, Nordmann P. Genetic basis of antibiotic resistance in pathogenic Acinetobacter species. IUBMB Life. 2011; 63(12):1061-7.

Antunes LC, Imperi F, Carattoli A, Visca P. Deciphering the multifactorial nature of Acinetobacter baumannii pathogenicity. PLoS One. 2011; 6(8):e22674.

López-Rojas R, Domínguez-Herrera J, McConnell MJ, Docobo-Peréz F, Smani Y, Fernández-Reyes M, et al. Impaired virulence and in vivo fitness of colistin-resistant Acinetobacter baumannii. J Infect Dis. 2011; 203(4):545-8.

Nourbakhsh F, Tajbakhsh E, Daneshmand D, Borooni S, Nourbakhsh V. Antibiotic Resistance Patterns and Molecular Typing of Acinetobacter Baumannii Strains Isolated from Burn Patients in Iran. Int J Med Lab. 2018; 5(4):278-87.

Shakibaie MR, Adeli S, Salehi MH. Antibiotic resistance patterns and extended-spectrum β-lactamase production among Acinetobacter spp. isolated from an intensive care Unit of a hospital in Kerman, Iran. Antimicrob Resist Infect Control. 2012; 1(1):1.

Shirmohammadlou N, Zeighami H, Haghi F, Kashefieh M. Resistance pattern and distribution of carbapenemase and antiseptic resistance genes among multidrug-resistant Acinetobacter baumannii isolated from intensive care unit patients. J Med Microbiol. 2018; 67(10):1467-73.

Kabbaj H, Seffar M, Belefquih B, Akka D, Handor N, Amor M, et al. Prevalence of Metallo-β-Lactamases Producing Acinetobacter baumannii in a Moroccan Hospital. ISRN Infect Dis. 2013; 2013:154921.

Amudhan MS, Sekar U, Kamalanathan A, Balaraman S. bla(IMP) and bla(VIM) mediated carbapenem resistance in Pseudomonas and Acinetobacter species in India. J Infect Dev Ctries. 2012; 6(11):757-62.

Al-Kadmy IMS, Ali ANM, Salman IMA, Khazaal SS. Molecular characterization of Acinetobacter baumannii isolated from Iraqi hospital environment. New Microbes New Infect. 2018; 21:51-7.

Momtaz H, Seifati SM, Tavakol M. Determining the Prevalence and Detection of the Most Prevalent Virulence Genes in Acinetobacter Baumannii Isolated From Hospital Infections. Int J Med Lab. 2015; 2(2):87-97.



  • There are currently no refbacks.

Copyright (c) 2021 © The Author(s)

Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.