Virulence Molecular Epidemiology of Clinical Carbapenem-Resistant Acinetobacter baumannii: A Report from Jordan
The Virulence of CRAB in Jordan
DOI:
https://doi.org/10.35516/jmj.v59i5.4146Keywords:
Acinetobacter, carbapenem, virulence, PCR, biofilmAbstract
Background and Aims: Carbapenem-resistant Acinetobacter baumannii (CRAB) is an opportunistic Gram-negative pathogen that plays a significant role in healthcare-associated infections, leading to severe health complications. While numerous studies have focused on the antibiotic-resistance epidemiology of A. baumannii, fewer have investigated its molecular virulence epidemiology. This study aimed to explore CRAB virulence genes, their biofilm-forming capabilities, and the correlation between biofilm formation and both biofilm-associated virulence genes and carbapenemase-encoding resistance genes.
Materials and Methods: A total of 110 CRAB clinical isolates were collected from two hospitals in Jordan between 2018 and 2019. These isolates were screened for at least seven virulence genes using polymerase chain reaction, and biofilm formation ability was evaluated using the microtiter plate method.
Results: the prevalence of the bap, OmpA, surA, PLD, paaE, basD, and traT virulence genes was 99.1%, 98.2%, 98.2%, 95.5%, 89.1%, 86.4%, and 8.2%, respectively. Overall, 86.4% of the isolates demonstrated biofilm-forming ability, classified as weak (28.2%), moderate (36.4%) and strong (21.8%). No statistically significant correlation was observed between biofilm production and the presence of bap, OmpA, or the carbapenemase-encoding gene (VIM gene). However, a significant relationship was identified between the carbapenemase-encoding gene (OXA-23 gene) and biofilm production.
Conclusions: CRAB infections pose a substantial threat in healthcare settings. This study underscores the critical need to enhance infection control measures in healthcare facilities to prevent CRAB outbreaks. To our knowledge, this is the first study in Jordan to examine the prevalence of virulence genes among clinical CRAB isolates.
References
Zhang P, Hao J, Zhang Y, Su J, Sun G, Xie J, et al. Understanding the clinical and molecular epidemiological characteristics of carbapenem-resistant Acinetobacter baumannii infections within intensive care units of three teaching hospitals. Ann Clin Microbiol Antimicrob. 2025. 24(1): p. 2.
Jung J, Park W. Acinetobacter species as model microorganisms in environmental microbiology: current state and perspectives. Appl Microbiol Biotechnol. 2015. 99: p. 2533-2548.
Tacconelli E, Carrara E, Savoldi A, Harbarth S, Mendelson M, Monnet DL, et al. Discovery, research, and development of new antibiotics: the WHO priority list of antibiotic-resistant bacteria and tuberculosis. Lancet Infect Dis. 2018. 18(3): p. 318-327.
Thummeepak R, Kongthai P, Leungtongkam U, Sitthisak SJIM. Distribution of virulence genes involved in biofilm formation in multi-drug resistant Acinetobacter baumannii clinical isolates. Int Microbiol. 2016. 19(2): p. 121-129.
Lukovic B, Kabic J, Dragicevic M, Kuljanin S, Dimkic I, Jovcic B, et al. Genetic basis of antimicrobial resistance, virulence features and phylogenomics of carbapenem-resistant Acinetobacter baumannii clinical isolates. Infection. 2025. 53(1): p. 39-50.
Doi Y, Murray GL, Peleg AY. Acinetobacter baumannii: evolution of antimicrobial resistance-treatment options. Semin Respir Crit Care Med. 2015. 36(1): p. 85-98.
Liu C, Chang Y, Xu Y, Luo Y, Wu L, Mei Z, et al. Distribution of virulence-associated genes and antimicrobial susceptibility in clinical Acinetobacter baumannii isolates. Oncotarget. 2018. 9(31): p. 21663.
Morris S, Cerceo E. Trends, epidemiology, and management of multi-drug resistant gram-negative bacterial infections in the hospitalized setting. Antibiotics. 2020. 9(4): p. 196.
Al-Tamimi M, Albalawi H, Alkhawaldeh M, Alazzam A, Ramadan H, Altalalwah M, et al. Multidrug-Resistant Acinetobacter baumannii in Jordan. Microorganisms. 2022. 10(5): p.
Smitran A, Lukovic B, Bozic L, Jelic D, Jovicevic M, Kabic J, et al. Carbapenem-Resistant Acinetobacter baumannii: Biofilm-Associated Genes, Biofilm-Eradication Potential of Disinfectants, and Biofilm-Inhibitory Effects of Selenium Nanoparticles. Microorganisms. 2023. 11(1): p.
Havill NL, Samuels M, Poudyal A, Sujanan V, Murdzek C, Aniskiewicz MJ, et al. Elimination of an outbreak of carbapenem-resistant Acinetobacter baumannii in a burn unit. Am J Infect Control. 2025. 53(1): p. 160-162.
Ibrahim S, Al-Saryi N, Al-Kadmy IM, Aziz SN. Multidrug-resistant Acinetobacter baumannii as an emerging concern in hospitals. Mol. Biol. Rep. 2021. 48(10): p. 6987-6998.
Zhang X, Li F, Awan F, Jiang H, Zeng Z, Lv W. Molecular Epidemiology and Clone Transmission of Carbapenem-Resistant Acinetobacter baumannii in ICU Rooms. Front Cell Infect Microbiol. 2021. 11: p. 633817.
Kyriakidis I, Vasileiou E, Pana ZD, Tragiannidis A. Acinetobacter baumannii Antibiotic Resistance Mechanisms. Pathogens. 2021. 10(3): p. 373.
Nguyen M, Joshi SJJoam. Carbapenem resistance in Acinetobacter baumannii, and their importance in hospital‐acquired infections: a scientific review. J. Appl. Microbiol. 2021. 131(6): p. 2715-2738.
Bostanghadiri N, Narimisa N, Mirshekar M, Dadgar-Zankbar L, Taki E, Navidifar T, et al. Prevalence of colistin resistance in clinical isolates of Acinetobacter baumannii: a systematic review and meta-analysis. Antimicrob Resist Infect Control. 2024. 13(1): p. 24.
Karakonstantis S, Rousaki M, Vassilopoulou L, Kritsotakis EI. Global prevalence of cefiderocol non-susceptibility in Enterobacterales, Pseudomonas aeruginosa, Acinetobacter baumannii, and Stenotrophomonas maltophilia: a systematic review and meta-analysis. Clin Microbiol Infect. 2024. 30(2): p. 178-188.
Adeloye D, Song P, Zhu Y, Campbell H, Sheikh A, Rudan I. Global, regional, and national prevalence of, and risk factors for, chronic obstructive pulmonary disease (COPD) in 2019: a systematic review and modelling analysis. Lancet Respir Med. 2022. 10(5): p. 447-458.
Wang M, Ge L, Chen L, Komarow L, Hanson B, Reyes J, et al. Clinical Outcomes and Bacterial Characteristics of Carbapenem-resistant Acinetobacter baumannii Among Patients From Different Global Regions. Clin. Infect. Dis. 2023. 78(2): p. 248-258.
Gharaibeh MH, Abandeh YM, Elnasser ZA, Lafi SQ, Obeidat HM, Khanfar MAJJoI, et al. Multi-drug resistant acinetobacter baumannii: phenotypic and genotypic resistance profiles and the associated risk factors in teaching hospital in Jordan. J Infect Public Health. 2024. 17(4): p. 543-550.
Park SM, Suh JW, Ju YK, Kim JY, Kim SB, Sohn JW, et al. Molecular and virulence characteristics of carbapenem-resistant Acinetobacter baumannii isolates: a prospective cohort study. Sci Rep. 2023. 13(1): p. 19536.
Sung JY, Koo SH, Kim S, Kwon GC. Persistence of Multidrug-Resistant Acinetobacter baumannii Isolates Harboring bla OXA-23 and bap for 5 Years. J Microbiol Biotechnol. 2016. 26(8): p. 1481-1489.
Fallah A, Rezaee MA, Hasani A, Barhaghi MHS, Kafil HS. Frequency of bap and cpaA virulence genes in drug resistant clinical isolates of Acinetobacter baumannii and their role in biofilm formation. Iran J Basic Med Sci. 2017. 20(8): p. 849.
Mozafari H, Mirkalantari S, Sadeghi Kalani B, Amirmozafari N. Prevalence Determination of Virulence Related and Biofilm Formation Genes in Acinetobacter baumannii Isolates from Clinical Respiratory Samples in Imam Khomeini Hospital, Tehran, Iran in 2018. Iran J Med Microbiol . 2021. 15(3): p. 266-280.
Depka D, Bogiel T, Rzepka M, Gospodarek-Komkowska E. The Prevalence of Virulence Factor Genes among Carbapenem-Non-Susceptible Acinetobacter baumannii Clinical Strains and Their Usefulness as Potential Molecular Biomarkers of Infection. Diagnostics. 2023. 13(6): p. 1036.
Hazhirkamal M, Zarei O, Movahedi M, Karami P, Shokoohizadeh L, Taheri M. Molecular typing, biofilm production, and detection of carbapenemase genes in multidrug-resistant Acinetobacter baumannii isolated from different infection sites using ERIC-PCR in Hamadan, west of Iran. BMC Pharmacol Toxicol. 2021. 22(1): p. 32.
Khoshnood S, Savari M, Abbasi Montazeri E, Farajzadeh Sheikh A. Survey on Genetic Diversity, Biofilm Formation, and Detection of Colistin Resistance Genes in Clinical Isolates of Acinetobacter baumannii. Infect Drug Resist. 2020. 13: p. 1547-1558.
Longo F, Vuotto C, Donelli G. Biofilm formation in Acinetobacter baumannii. New Microbiol. 2014. 37(2): p. 119-127.
Abdi-Ali A, Hendiani S, Mohammadi P, Gharavi S. Assessment of biofilm formation and resistance to imipenem and ciprofloxacin among clinical isolates of Acinetobacter baumannii in Tehran. Jundishapur J. Microbiol.. 2014. 7(1): e8606.
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: p. 122-128.
Özkul C, Hazırolan G. Oxacillinase gene distribution, antibiotic resistance, and their correlation with biofilm formation in Acinetobacter baumannii bloodstream isolates. Microb Drug Resis. 2021. 27(5): p. 637-646.
Eze EC, Chenia HY, El Zowalaty ME. Acinetobacter baumannii biofilms: effects of physicochemical factors, virulence, antibiotic resistance determinants, gene regulation, and future antimicrobial treatments. Infect Drug Resist. 2018. p. 2277-2299.
