Frequency of Type Ⅱ Secretory Exotoxin Encoding Gene in Clinical Isolates of Pseudomonas aeruginosa Collected from Surgical Ward Patients

Document Type : Original Article (s)

Authors

1 PhD Candidate in Microbiology, Department of Microbiology and Microbial Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran

2 Associate Professor, Department of Microbiology and Microbial Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran

3 Professor, Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran

4 Assistant Professor, Department of Pathology, Shiraz Medical School, AND Shiraz Transplant Center, Abu Ali Sina Hospital, Shiraz University of Medical Sciences, Shiraz, Iran

Abstract

Background: As an opportunistic pathogen, Pseudomonas aeruginosa is one of the most important causes of hospital-acquired infections. Its high pathogenicity can be attributed to multiple virulence factors. Identifying pathogenic factors can help in designing effective treatments. The present study was conducted with the aim of investigating the pattern of antibiotic resistance and toxA virulence gene in clinical isolates of P. aeruginosa collected from surgical ward patients.
Methods: 50 isolates of P. aeruginosa were collected from different samples and identified using conventional biochemical tests. Antimicrobial sensitivity was tested using the disk diffusion method. The multiple antibiotic resistance index (MAR) was calculated. DNA was extracted using the boiling method, and PCR was performed to detect toxA virulence gene.
Findings: Among the 50 isolates, (56%) were obtained from men and (44%) from women. Patients were in the age range of 1-89 years. Most bacteria isolation was performed in the surgical unit (26%), intensive care unit (24%), and emergency unit (18%). Isolates exhibited high sensitivity to amikacin (62%) and cefepime (60%) antibiotics. The highest resistance rate was observed against imipenem (46%). Forty-four percent of the isolates were multidrug-resistant (MDR). The MAR index ranged from 0 to 1. The Mean MAR index of isolates was 0/38. Frequency of the toxA virulence gene (96%) was determined.
Conclusion: This study highlights the high prevalence of the virulence factor gene toxA and its importance in the pathogenicity of P. aeruginosa. Identification of virulence factors is crucial for effective infection control measures and the development of targeted therapeutic strategies.

Highlights

Maryam Behboudipour: Google Scholar 

Neda Soleimani: Google Scholar 

Keywords

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References

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Journal of Isfahan Medical School
Volume 43, Issue 815
3rd Week, July
July and August 2025
Pages 506-514

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History

  • Receive Date: 19 January 2025
  • Accept Date: 11 August 2025

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