Prevalence of Quorum Sensing and Virulence Factor Genes Among Isolated from Patients Suffering from Different Infections and Their Association with Antimicrobial Resistance.

Purpose: Antimicrobial resistance and virulence genes play important roles in increasing the severity of infections, especially in hospitalized patients with high antibiotic pressure. Most genes that encode virulence factors are controlled and regulated by the quorum sensing (QS) system. The aim of this study was to investigate the frequency of some virulence genes ( genes) and their association with antibiotic resistance.

Methods: Antimicrobial susceptibility was determined by Kirby-Bauer agar disk diffusion method. A total of 125 clinical isolates of were tested for some virulence genes using polymerase chain reaction (PCR).

Results: The highest resistance was observed against cefepime (92.8%). Multi-drug resistant (MDR) represented 63.2% of total isolates with high distribution among wound isolates (21/79, 26.3% of MDR isolates). was the most prevalent virulence gene among the tested isolates (89.6%) followed by (85.6%), (84%), (80%), (76.8%), and (75.2). Furthermore, a significant association (P < 0.05) among most of the tested virulence genes and MDR isolates was found. The presence of more than 5 virulence genes was highly observed among wound infections, otitis media, and respiratory tract infection isolates.

Conclusion: The complex association of virulence genes including QS system regulating genes with antibiotic resistance indicates the importance of the tested factors in the progression of infections, which is considered a great challenge for the health-care team with the need for specific studies for each area having different antibiotic resistance profiles and the development of effective treatment strategies such as anti-virulent and quorum sensing inhibiting drugs against infections.