Correlation between antibiotic resistance and virulence of Pseudomonas aeruginosa clinical isolates

Area of Science:

• Clinical Microbiology
• Molecular Biology
• Infectious Diseases

Background:

• Virulent *Pseudomonas aeruginosa* is a life-threatening pathogen, with multidrug-resistant (MDRPA) strains posing a critical clinical challenge.
• Understanding the genetic basis of virulence and antimicrobial resistance in MDRPA is essential for effective treatment strategies.

Purpose of the Study:

• To perform a molecular analysis of virulence factors in multidrug-resistant *Pseudomonas aeruginosa* (MDRPA).
• To determine the antimicrobial resistance profile of MDRPA isolates.
• To investigate the correlation between virulence factors and antimicrobial resistance markers in MDRPA.

Main Methods:

• Selected 12 multidrug-resistant *Pseudomonas aeruginosa* (MDRPA) isolates from 44 identified strains based on resistance profiles and sample sources.
• Employed Polymerase Chain Reaction (PCR) techniques to identify genes associated with antimicrobial resistance and virulence factors.
• Analyzed specific genes including *pstS*, *bla* (IMP types, *blaOXA50*, *blaOXA2*), *plcH*, and *toxA*.

Main Results:

• All selected MDRPA isolates carried multidrug-resistance (*pstS*), β-lactamase (*IMP7, IMP10, IMP13, IMP25*), and extended-spectrum β-lactamase (*blaOXA50*) genes.
• The *blaOXA2* gene was present in 33% of MDRPA isolates, while the hemolytic phospholipase C precursor (*plcH*) gene was detected in all isolates.
• The exotoxin A (*toxA*) gene was notably absent in all tested MDRPA isolates; other virulence genes showed variable presence.

Conclusions:

• A significant positive correlation (r = 0.779, P = 0.002) was established between the presence of virulence factors and antimicrobial resistance marker profiles in MDRPA.
• These findings highlight the genetic interplay between virulence and resistance in *Pseudomonas aeruginosa*, informing clinical management of infections caused by these challenging pathogens.