Prevalence and genotypic distribution of virulence factor genes and antibiotic susceptibility profiles in clinical Pseudomonas aeruginosa isolates from a public hospital in Nanyang, China.

内容摘要

Pseudomonas aeruginosa remains a critical global health concern, particularly in low- and middle-income countries, owing to its high carriage of diverse virulence factor genes (VFGs) and multidrug resistance. Here, we analyzed the prevalence and genotype distribution of VFGs in P. aeruginosa isolated from Nanyang Central Hospital (NYCH), China, along with their antibiotic susceptibility profiles. The study involved 79 multidrug-resistant (MDR) and 96 non-MDR (nMDR) strains and the following 11 key VFGs (nan1, pilA, aprA, phzS, plcH, toxA, lasB, exoS, exoU, exoT, exoY). Antibiogram profiling showed near-universal resistance to at least one antibiotic class. MDR strains exhibited 23 distinct antibiotic resistance patterns, compared with 13 patterns in nMDR strains. A moderate negative correlation was observed between &#x3b2;-lactams/&#x3b2;-lactamase inhibitors and fluoroquinolone resistance. Moreover, statistical analysis revealed that the phzS gene displayed the most significant prevalence difference between MDR and nMDR subgroups (P < 0.001). Finally, 28 distinct genotypes were identified in nMDR isolates, and 26 genotypes appeared in MDR strains. There was a statistically significant correlation found between the presence of genotype XX (r = 0.481, P < 0.001) and genotype XXVIII (r = -0.320, P < 0.001) in two subgroups. Collectively, our findings provide data support for understanding the pathogenic mechanism of local P. aeruginosa, and are of great significance for guiding clinical anti-infection treatment and infection control.IMPORTANCEPseudomonas aeruginosa is an opportunistic pathogen notorious for causing difficult-to-treat infections, particularly among hospitalized patients in resource-limited healthcare settings. This study analyzed clinical isolates from a major hospital in China to investigate the prevalence and genotypic distribution of virulence factor genes (VFGs) and antibiotic susceptibility profiles of P. aeruginosa. Our results showed that multidrug-resistant (MDR) strains displayed more complex and diverse resistance profiles than non-MDR (nMDR) strains. Both MDR and nMDR isolates exhibited high genotypic diversity. Notably, a statistically significant association was observed between genotype XX and genotype XXVIII across the two subgroups. These findings elucidate the molecular basis underlying the variable treatment difficulty of P. aeruginosa infections and offer valuable insights for guiding empirical antibiotic selection. Characterizing local bacterial features, including antibiotic susceptibility profiles and the distribution of clinically relevant virulence factors, may improve understanding of regional resistance trends and support antimicrobial stewardship and infection control efforts.