<p><i>Pseudomonas aeruginosa</i> is a clinically significant opportunistic pathogen characterized by intrinsic and acquired resistance mechanisms coupled with a diverse array of virulence determinants. This study investigated the distribution of <i>P. aeruginosa</i> in various clinical specimens (<i>n =</i> 382), its virulence genes, antimicrobial resistance patterns, and associations with total resistant <i>P. aeruginosa</i> (TRPA) phenotypes. The majority of isolates were recovered from sputum (24.3%) and endotracheal tube samples (22.5%). Virulence gene screening revealed moderate-to-high prevalence of <i>lasB</i> (55.0%), <i>toxA</i> (49.7%), <i>pilA</i> (53.7%), <i>aprA</i> (56.5%), <i>phzS</i> (45.0%), <i>exoS</i> (41.9%), and <i>exoU</i> (38.0%), indicating their widespread involvement in pathogenicity. Antimicrobial susceptibility profiling demonstrated the highest susceptibility to amikacin (56.3%) and gentamicin (52.4%), while resistance to carbapenems (imipenem 52.4%, meropenem 52.9%) and cephalosporins was alarmingly high. Based on resistance classification, 33.5% of isolates were MDR, and 9.7% XDR. Among ceftazidime-resistant isolates (<i>n =</i> 200), 83% harboured ESBL genes, with <i>bla</i><sub><i>CTX-M</i></sub> (38.0%) being most prevalent. Notably, 30.7% and 22.8% of isolates carried <i>bla</i><sub><i>NDM-1</i></sub> and bla<sub><i>OXA-48</i></sub>, respectively. Comparative analysis demonstrated statistically significant associations between TRPA phenotype and virulence genes: <i>lasB</i> (OR = 90.3), <i>toxA</i> (OR = 260.9), and <i>pilA</i> (OR = 32.6) (<i>p &lt;</i> 0.0001). Resistance determinants such as <i>bla</i><sub><i>CTX-M</i></sub> (OR = 3.5), <i>aac(6′)-Ib</i> (OR = 2.9), <i>qnrA</i> (OR = 3.9), and co-carriage of <i>NDM-1</i> + <i>OXA-48</i> (OR = 4.9) were significantly enriched in TRPA isolates. These findings demonstrate a significant association between virulence and antimicrobial resistance traits, emphasizing the potential expansion of high-risk <i>P. aeruginosa</i> clones in clinical settings and highlighting the need for genomic surveillance and antimicrobial stewardship interventions.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Molecular characterization of virulence and resistance determinants in clinical Pseudomonas aeruginosa isolates: a cross-sectional analysis of virulence–resistance associations

  • Soha Abdallah Moursi,
  • Mohd Saleem,
  • Alharbi Mohammed Salem,
  • Ehab Badran Mohammed Rakha,
  • Ahmed Nawi Alshammari,
  • Rana Aboras,
  • AzharuddinSajid SyedKhaja,
  • Ashfaque Hossain

摘要

Pseudomonas aeruginosa is a clinically significant opportunistic pathogen characterized by intrinsic and acquired resistance mechanisms coupled with a diverse array of virulence determinants. This study investigated the distribution of P. aeruginosa in various clinical specimens (n = 382), its virulence genes, antimicrobial resistance patterns, and associations with total resistant P. aeruginosa (TRPA) phenotypes. The majority of isolates were recovered from sputum (24.3%) and endotracheal tube samples (22.5%). Virulence gene screening revealed moderate-to-high prevalence of lasB (55.0%), toxA (49.7%), pilA (53.7%), aprA (56.5%), phzS (45.0%), exoS (41.9%), and exoU (38.0%), indicating their widespread involvement in pathogenicity. Antimicrobial susceptibility profiling demonstrated the highest susceptibility to amikacin (56.3%) and gentamicin (52.4%), while resistance to carbapenems (imipenem 52.4%, meropenem 52.9%) and cephalosporins was alarmingly high. Based on resistance classification, 33.5% of isolates were MDR, and 9.7% XDR. Among ceftazidime-resistant isolates (n = 200), 83% harboured ESBL genes, with blaCTX-M (38.0%) being most prevalent. Notably, 30.7% and 22.8% of isolates carried blaNDM-1 and blaOXA-48, respectively. Comparative analysis demonstrated statistically significant associations between TRPA phenotype and virulence genes: lasB (OR = 90.3), toxA (OR = 260.9), and pilA (OR = 32.6) (p < 0.0001). Resistance determinants such as blaCTX-M (OR = 3.5), aac(6′)-Ib (OR = 2.9), qnrA (OR = 3.9), and co-carriage of NDM-1 + OXA-48 (OR = 4.9) were significantly enriched in TRPA isolates. These findings demonstrate a significant association between virulence and antimicrobial resistance traits, emphasizing the potential expansion of high-risk P. aeruginosa clones in clinical settings and highlighting the need for genomic surveillance and antimicrobial stewardship interventions.