Prevalence of exoA, cepA, plcH, lasB, and algD virulence genes in clinical isolates of Pseudomonas aeruginosa from hospitals in Yasuj and Shiraz, Iran

Arash Hasannezhad; Hadi Ebrahimi; Afshin Mansourian; Owrang Eilami; Asghar Sharifi; Seyed Abdolmajid Khosravani

doi:10.18502/ijm.v17i6.20363

Arash Hasannezhad Department of Microbiology, School of Medicine, Yasuj University of Medical Sciences, Yasuj, Iran
Hadi Ebrahimi Student Research Committee, Yasuj University of Medical Sciences, Yasuj, Iran
Afshin Mansourian Department of Anesthesiology, Yasuj University of Medical Sciences, Yasuj, Iran
Owrang Eilami HIV and AIDS Research Center, Department of Infectious Disease and Family Medicine, Shiraz University of Medical Science, Shiraz, Iran
Asghar Sharifi Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran
Seyed Abdolmajid Khosravani Cellular and Molecular Research Center, Yasuj University of Medical Sciences, Yasuj, Iran

DOI: https://doi.org/10.18502/ijm.v17i6.20363

Keywords: Antibiotic resistance; Virulence; Pseudomonas aeruginosa; Polymerase chain reaction

Abstract

Background and Objectives: Pseudomonas aeruginosa, an opportunistic Gram-negative bacterium, is ubiquitous and rep- resents one of the most challenging multidrug-resistant pathogens today. This multicenter study aimed to evaluate antibiotic resistance patterns, detect the cepA antibiotic resistance gene, and identify virulence factor genes (exoA, algD, lasB, and plcH) in clinical isolates of P. aeruginosa.

Materials and Methods: This experimental study analyzed 74 P. aeruginosa isolates obtained from clinical samples at Imam Sajad (Yasuj) and Namazi (Shiraz) hospitals, including 74 clinical isolates and one standard reference strain. Bacterial identification was performed using standard biochemical tests. Antibiotic susceptibility was assessed by the disk diffusion method according to CLSI 2018 guidelines. Genomic DNA was extracted by means of boiling method, and PCR assays were applied to detect exoA, cepA, plcH, lasB, and algD genes. Data were analyzed with chi-square tests, considering p<0.05 as statistically significant.

Results: Among 74 P. aeruginosa isolates, all carried the exoA gene, while algD, plcH, cepA, and lasB were detected in 95.6%, 94.6%, 93.2%, and 91.9% of isolates, respectively. High resistance was observed to aztreonam and ticarcillin, while cefiderocol showed the greatest sensitivity. A significant correlation was found between the cepA gene and antibiotic resis- tance (P = 0.03).

Conclusion: This study reveals a high prevalence of virulence genes and increasing antibiotic resistance among P. aerugino- sa clinical isolates, highlighting the urgent need for effective therapeutic strategies to combat this pathogen.