Hospital Practices and Research

Assessment of the Frequency of qnrS and qnrA Genes in Clinical Isolates of Klebsiella pneumoniae and Their Relationship with Antibiotic Resistance Patterns and Iron Oxide Nanoparticles

Document Type : Original Article

Authors

Zahra Malekzadeh 1
Zahra Hojjati Bonab 2
Hossein Soltanzadeh 1

1 Department of Biology, Bon.C., Islamic Azad University, Bonab, Iran

2 Department of Microbiology, Bon.C., Islamic Azad University, Bonab, Iran

https://doi.org/10.30491/hpr.2025.485003.1457
Abstract
Background: Klebsiella pneumoniae is a gram-negative, short, facultative anaerobic bacillus that commonly grows in laboratory culture environments, including blood agar, EMB, Mueller-Hinton agar, and nutrient agar. As an opportunistic pathogen, it poses significant treatment challenges due to increasing antibiotic resistance.
Objectives: The purpose of this study is to determine the relationship between antibiotic resistance and the frequency of qnrS and qnrA genes in clinical isolates of Klebsiella pneumonia.
Methods: In this study, 100 patients referred to Sina Hospital in Tabriz due to urinary tract infections (UTIs) were examined. Common biochemical tests confirmed the presence of Klebsiella in 20 samples. The antibiotic sensitivity pattern of the isolates was determined using the disc diffusion method, and the results of the antibiogram test were analyzed. The resistance of the samples to five different types of antibiotics was assessed.
Results: In this study, the highest antibiotic resistance was observed against nalidixic acid. The presence of the qnrS gene was confirmed in five isolates of Klebsiella pneumoniae, while the qnrA gene was absent in all isolates. The sensitivity of the Klebsiella pneumoniae strain to iron oxide nanoparticles was evaluated using the well method at a concentration of 0.08 g in 100 ml of water. One sample in a volume of 100 ml and two samples in a volume of 200 ml formed halos with diameters of 11 mm, 14 mm, and 12 mm, respectively.
Conclusion: The findings of the present study showed that the frequency of qnrS genes was high in fluoroquinolone-resistant samples of Klebsiella pneumoniae, and this factor could lead to progressive antimicrobial resistance in different hospital departments.

Keywords

Klebsiella pneumoniae
Antibiotic Resistance
qnrA Gene
qnrS Gene
Iron Oxide Nanoparticles
  1. Dong N, Yang X, Chan EW, Zhang R, Chen S. Klebsiella species: taxonomy, hypervirulence and multidrug resistance. EBioMedicine. 2022;79:103998. doi:10.1016/j.ebiom.2022.103998
  2. Livermore DM. Current epidemiology and growing resistance of gram-negative pathogens. Korean J Intern Med. 2012;27(2):128-42. doi:10.3904/kjim.2012.27.2.128
  3. Lu PL, Liu YC, Toh HS, Lee YL, Liu YM, Ho CM, et al. Epidemiology and antimicrobial susceptibility profiles of Gram-negative bacteria causing urinary tract infections in the Asia-Pacific region: 2009-2010 results from the Study for Monitoring Antimicrobial Resistance Trends (SMART). Int J Antimicrob Agents. 2012;40:S37-43. doi:10.1016/S0924-8579(12)70008-0
  4. Alfaifi BA, AlKhaldi SA, AlHomoud KA, Shuraim WA. Epidemiology and Antibiotic Resistance Patterns of Klebsiella pneumoniae Infections Among Female Patients of a Long-Term Care Hospital in Saudi Arabia. Cureus. 2025;17(3):e80008. doi:10.7759/cureus.80008
  5. Millanao AR, Mora AY, Villagra NA, Bucarey SA, Hidalgo AA. Biological Effects of Quinolones: A Family of Broad-Spectrum Antimicrobial Agents. Molecules. 2021;26(23):7153. doi:10.3390/molecules26237153
  6. Hooper DC, Jacoby GA. Topoisomerase Inhibitors: Fluoroquinolone Mechanisms of Action and Resistance. Cold Spring Harb Perspect Med. 2016;6(9):a025320. doi:10.1101/cshperspect.a025320
  7. Wang L, Hu C, Shao L. The antimicrobial activity of nanoparticles: present situation and prospects for the future. Int J Nanomedicine. 201712:1227-1249. doi:10.2147/IJN.S121956
  8. Kotrange H, Najda A, Bains A, Gruszecki R, Chawla P, Tosif MM. Metal and Metal Oxide Nanoparticle as a Novel Antibiotic Carrier for the Direct Delivery of Antibiotics. Int J Mol Sci. 2021;22(17):9596. doi:10.3 390/ijms22179596
  9. Berry CC, Wells S, Charles S, Curtis AS. Dextran and albumin derivatised iron oxide nanoparticles: influence on fibroblasts in vitro. Biomaterials. 2003;24 (25):4551-7. doi:10.1016/S0142-9612(03)00237-0
  10. Wang M, Sahm DF, Jacoby GA, Hooper DC. Emerging plasmid-mediated quinolone resistance associated with the qnr gene in Klebsiella pneumoniae clinical isolates in the United States. Antimicrob Agents Chemother. 2004;48(4):1295-9. doi:10.1128/aac.48.4.1295-1299.2004
  11. Rezazadeh M, Baghchesaraei H, Peymani A. Plasmid-Mediated Quinolone-Resistance (qnr) Genes in Clinical Isolates of Escherichia coliCollected from Several Hospitals of Qazvin and Zanjan Provinces, Iran. Osong Public Health Res Perspect. 2016;7(5): 307-312. doi:10.1016/j.phrp.2016.08.003
  12. Mubaraki MA, Ali J, Khattak B, Fozia F, Khan TA, Hussain M, et al. Characterization and Antibacterial Potential of Iron Oxide Nanoparticles in Eradicating Uropathogenic coli. ACS Omega. 2023;9(1):166-177. doi:10.1021/acsomega.3c03078
  13. Salimbahrami S R, Ahanjan M, Goli H R, Akhoondian M, Gholami M. Phenotypic and Genotypic Evaluation of Resistance to Fluoroquinolones in Klebsiella pneumoniae Collected from Hospitalized Patients in Sari, Iran. J Mazandaran Univ Med Sci. 2021;31(196): 101-10
  14. Hashemi A, Fallah F, Taherpour A, Goudarzi H, Tarashi S, Erfanimanesh S, et al. Detection of metallo-beta-lactamases, extended-spectrum beta-lactamases (ESBLs), outer membrane porins among Klebsiella pneumoniae strains isolated from hospitalized patients in Tehran. J Adv Med Biomed Res. 2015;23(98):89-102.
  15. Nourozi M, Mirkalantari S, Omidi S. Frequency of plasmid-mediated quinolone resistance genes qnrA, qnrB, and qnrS among clinical isolates of Klebsiella pneumoniae. J Appl Biotechnol Rep. 2020;7(4):203-7. doi:10.30491/jabr.2020.120187
  16. Gheysarzadeh A, Pakzad I, Valadbeigi H, Maleki A, Sadeghifard N. Antimicrobial resistance and genetic analysis of multi-drug resistant Klebsiella pneumoniae isolates by pulsed-field gel electrophoresis. Gene Rep. 2020;19:100638. doi:10.1016/j.genrep.2020.100638
  17. Unlu O, Demirci M. Detection of carbapenem-resistant Klebsiella pneumoniae strains harboring carbapenemase, beta-lactamase and quinolone resistance genes in intensive care unit patients. GMS Hyg Infect Control. 2020;15:Doc31. doi:10.3205/dgkh000366
  18. Gholam nezhad M, Hassanzadeh S, Afroughi S, Khorram rouz S, Shabani M, Masnavi E. Investigation of the Frequency of Plasmid-Dependent Quinolone Resistance Genes in Klebsiella pneumoniae, Pseudomonas aeruginosa and Escherichia coli Isolated from Surgical Site Infections. Armaghanj. 2022;27(6):745-57. doi:10.52547/armaghanj.27.6.745

Home

Guide for Authors

Submit Manuscript

Reviewers

Contact Us