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

Abstract

Purpose Antimicrobial resistance and virulence genes play important roles in increasing the severity of Pseudomonas aeruginosa infections, especially in hospitalized patients with high antibiotic pressure. Most genes that encode Pseudomonas aeruginosa 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 ( rhlR, rhlI, lasR, lasI, lasB, toxA, aprA, algD, ExoS, and plcH 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 P. aeruginosa 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) P. aeruginosa represented 63.2% of total isolates with high distribution among wound isolates (21/79, 26.3% of MDR isolates). LasB was the most prevalent virulence gene among the tested isolates (89.6%) followed by aprA (85.6%), exoS (84%), algD (80%), toxA (76.8%), and plcH (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 P. aeruginosa infections.

Enzyme Production and Inhibitory Potential of Pseudomonas aeruginosa: Contrasting Clinical and Environmental Isolates

“…This finding was in line with previous studies that reported varying frequencies of gelatinase production in P. aeruginosa isolates from clinical sources [18,19]. The presence of gelatinase in wound and urine samples, indicating its potential role in tissue damage and urinary tract infections, was supported by previous research that implicated gelatinase in P. aeruginosa pathogenesis [20,21].…”

“…When comparing these results with previous studies, it is evident that the inhibitory effects of P. aeruginosa strains can vary among different environmental sources and target pathogens. These data suggest the presence of different antimicrobial mechanisms employed by the strains [ 20 , 21 ]. Further research is needed to understand these mechanisms and their potential applications in combating pathogens.…”

Determination of Antimicrobial Resistance and the Impact of Imipenem + Cilastatin Synergy with Tetracycline in Pseudomonas aeruginosa Isolates from Sepsis

“…As anticipated, the presence of this gene was observed in all strains, exhibited biofilm production, and demonstrated varying levels of resistance to antimicrobial agents. Other studies corroborate ours in relation to the high percentage of detection of toxA and algD genes [63,64] lasB genes were found in all strains, while lasA genes appeared in 26.32% of isolates. Usually, these genes encode proteins secreted by the type II secretion system, which plays a major role during infection.…”

“…This observation implies that P. aeruginosa exhibits a diverse repertoire of lasB enzymes, which have likely evolved to accommodate various environments and hosts. The prevalence of lasB in other studies is also high, which indicates that, in isolates of P. aeruginosa, this gene is highly distributed [63,64,66]. Variation in lasA gene recognition may influence the specific populations and clinical settings studied.…”

“…These two genes have significance in biofilm formation, adaptation, and cytotoxicity. Studies have demonstrated the high prevalence of aprA; for example, Ghanem et al detected the gene in 85.6% of isolates and the gene plcH in 75.2% [63]. The tssC gene, despite not directly influencing biofilm formation, is associated with biofilm-specific antibiotic resistance [62].…”