Detection of carbapenemase in acinetobacter baumannii enrolled in the relationship between biofilm formation and antibiotic resistance


  • Sayran S. Qader Department of Clinical Analysis, College of Pharmacy, Hawler Medical University, Erbil, Iraq
  • Aryan R. Ganjo Department of Clinical Analysis, College of Pharmacy, Hawler Medical University, Erbil, Iraq / Department of Medical Analysis, Faculty of Applied Science, Tishk International University, Erbil, Iraq



Acinetobacter baumannii, Carbapenemase, Biofilm development, Antibiotic susceptibility


Background and objective: Acinetobacter baumannii is a significant pathogenic bacterium in the health system. The ability to resist antimicrobial drugs and biofilm formation gives the considerable capacity to A. baumannii for existing in a harsh environment, enabling this bacterium to cause hospital-acquired infection. Carbapenem is an important treatment option for severe nosocomial infection and patients infected by multidrug-resistant organisms. The main aim of this study is to detect carbapenemase in isolates, and its association with biofilm formation as well as antibiotic resistance.

Methods: Sixty A. baumannii isolates were obtained from several hospital districts in Erbil city. Identification and antimicrobial susceptibility test (AST) of isolates were performed by VITEKII compact system. Phenotypic identification of carbapenem by sCIM also biofilm-forming was detected by 96 well method. Additionally, three antimicrobial agents were used if they were successful in eliminating biofilm formation. .

Results: The majority of the isolates were from sputum, accounting 75% and antibiotic susceptibility showed that the isolates are resistant to the most available antibiotics, and significant of the isolates formed strong biofilm. The sensitivity of meropenem, ceftazidime, and ciprofloxacin were employed for ten isolates of A. baumannii after biofilm formation it was found that biofilm cells need more concentration of antibiotic than planktonic cells then phenotypic detection of carbapenem showed that the overall positive values were 30 (50.0%) for sCIM.

Conclusion: We revealed that most resistant isolates have a greater capacity for biofilm development than sensitivite isolates. Biofilm-producing strains of A. baumannii cannot be killed with the relatively similar concentration of antimicrobial drugs that are needed to kill planktonic cells.


Metrics Loading ...


Yadav SK, Bhujel R, Hamal P, Mishra SK, Sharma S, Sherchand JB. Burden of multidrug-resistant Acinetobacter baumannii infection in hospitalized patients in a tertiary care hospital of Nepal. Infect Drug Resist. 2020; 13:725. doi:10.2147/IDR.S239514.

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):1–5. doi: 10.1186/s13104-019-4344-7.

Patel SJ, Oliveira AP, Zhou JJ, 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.

Gedefie A, Demsis W, Ashagrie M. Acinetobacter baumannii biofilm formation and its role in disease pathogenesis: A review. Infect Drug Resist. 2021; 14: 3711. doi:10.2147/IDR.S332051.

Basatian-Tashkan B, Niakan M, Khaledi M. 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):1–6.

Rit K, Saha R. Multidrug-resistant acinetobacter infection and their susceptibility patterns in a tertiary care hospital. Niger Med J. 2012; 53(3):126. doi: 10.4103/0300-1652.104379.

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. Public Health Front. 2016; 4:105.

Lee C-R, Lee JH, Park M, Biology of Acinetobacter baumannii: pathogenesis, antibiotic resistance mechanisms, and prospective treatment options. Front Cell Infect Microbiol. 2017: 55.

Qi L, Li H, Zhang C, Relationship between antibiotic resistance, biofilm formation, and biofilm-specific resistance in Acinetobacter baumannii. Front Microbiol. 2016; 7:483. doi10.3389/fmicb.2016.00483.

Smai SB. A Prevalence of infections with antibiotic-resistant Acinetobacter baumannii in different clinical samples from hospitals in Erbil. ZJPAS. 2020; 32(3):95–100.

Bushand K, Jacoby G. Updated functional classification of ?–lactamases. Antimicrob. Agents Chemother. 2010; 54(3):969–76.

Wang Y-C, Huang T-W, Yang Y-S. Biofilm formation is not associated with worse outcome in Acinetobacter baumannii bacteraemic pneumonia. Sci Rep. 2018; 8(1):1–10. doi: 10.1038/s41598-018-25661-9.

Badave GK, Kulkarni D. Biofilm producing multidrug resistant Acinetobacter baumannii: an emerging challenge.J Clin Diagn Res. 2015; 9(1). doi: 10.7860/JCDR/2015/11014.5398

Yang C-H, Su P-W, Moi S-H, Chuang L-Y. Biofilm formation in Acinetobacter Baumannii: genotype-phenotype correlation. Molecules. 2019; 24(10):1849. doi: 10.3390/molecules24101849.

Chmielarczyk A, Pilarczyk-Żurek M, Kamińska W, Molecular epidemiology and drug resistance of Acinetobacter baumannii isolated from hospitals in southern Poland: ICU as a risk factor for XDR strains. Microb Drug Resist. 2016; 22(4): 328–35.

Bardbari AM, Arabestani MR, Karami M, Keramat F, Alikhani MY, Bagheri KP. Correlation between ability of biofilm formation with their responsible genes and MDR patterns in clinical and environmental Acinetobacter baumannii isolates. Microb Pathog. 2017; 108:122–8. doi: 10.1016/j.micpath.2017.04.039.

Li Z, Ding Z, Liu Y, Phenotypic and genotypic characteristics of biofilm formation in clinical isolates of Acinetobacter baumannii. Infect Drug Resist. 2021; 14:2613.

Weinstein MP. Performance standards for antimicrobial susceptibility testing: Clinical and Laboratory Standards Institute; 2021.

Jing X, Zhou H, Min X.The simplified carbapenem inactivation method (sCIM) for simple and accurate detection of carbapenemase-producing gram-negative bacilli. Front Microbiol. 2018:2391.

Tavakol M, Momtaz H, Mohajeri P, Shokoohizadeh L, Tajbakhsh E. Genotyping and distribution of putative virulence factors and antibiotic resistance genes of Acinetobacter baumannii strains isolated from raw meat. Antimicrob Resis Infect Control. 2018; 7(1):1–11.

Wang H, Wang J, Yu P. Identification of antibiotic resistance genes in the multidrug-resistant Acinetobacter baumannii strain, MDR-SHH02, using whole-genome sequencing. Int J Mol Med. 2017; 39(2):364–72.

Khuntayaporn P, Thirapanmethee K, Kanathum P, Chitsombat K, Chomnawang MT. Comparative study of phenotypic-based detection assays for carbapenemase-producing Acinetobacter baumannii with a proposed algorithm in resource-limited settings. Plos one. 2021; 16(11):e0259686.

Ganjo AR, Maghdid DM, Mansoor IY. OXA-carbapenemases present in clinical Acinetobacter baumannii-calcoaceticus complex isolates from patients in Kurdistan region, Iraq. Microb. Drug Resist. 2016; 22(8):627–37.

Smail SB, AL-Otrachi KI. Phenotypic Characterization of Extended-Spectrum Beta-Lactamases and Metallo-Beta-Lactamase of Multi Drug Resistant Acinetobacter baumannii Causing Nosocomial Infections in Erbil City. Al-Mustansiriyah J Sci. 2020; 30:51–6.

Howard JC, Creighton J, Ikram R, Werno AM. Comparison of the performance of three variations of the Carbapenem Inactivation Method (CIM, modified CIM [mCIM] and in-house method (iCIM)) for the detection of carbapenemase-producing Enterobacterales and non-fermenters. J. Glob. Antimicrob. Resist. 2020; 21:78–82. doi: 10.1016/j.jgar.2020.03.021.

Al-Shamiri MM, Zhang S, Mi P. Phenotypic and genotypic characteristics of Acinetobacter baumannii enrolled in the relationship among antibiotic resistance, biofilm formation and motility. Microb. Pathog. 2021; 155:104922.

AL-Mousawi HT, AL-Taee MIN, AL-Hajjar QN. Evaluation of Biofilm Formation Capacity of Acinetobacter baumannii Isolated from Clinical Samples in Baghdad Hospitals using Phenotypic Methods. Iraqi J biotech. 2018; 17(3).

Sung JY. Molecular characterization and antimicrobial susceptibility of biofilm-forming Acinetobacter baumannii clinical isolates from Daejeon, Korea. Korean J Clin Lab Sci. 2018; 50(2): 100–9.

Eze EC, El Zowalaty ME, Pillay M. Antibiotic resistance and biofilm formation of Acinetobacter baumannii isolated from high-risk effluent water in tertiary hospitals in South Africa. J. Glob. Antimicrob. Resist. 2021; 27: 82–90.

Shenkutie AM, Yao MZ, Siu GK-h, Wong BKC, Leung PH-m. Biofilm-induced antibiotic resistance in clinical Acinetobacter baumannii isolates. Antibiotics. 2020; 9(11):817.




How to Cite

S. Qader, S. ., & R. Ganjo, A. . (2023). Detection of carbapenemase in acinetobacter baumannii enrolled in the relationship between biofilm formation and antibiotic resistance. Zanco Journal of Medical Sciences (Zanco J Med Sci), 27(1), 74–84.



Original Articles