Correlation between antibiotic resistance and virulence ofPseudomonas aeruginosa clinical isolates

Abstract

IntroductionThe increasing frequency of multidrug-resistant Pseudomonas aeruginosa (MDRPA) strains is concerning, as efficacious antimicrobial options are severely limited. Risk factors for MDRPA infection include prolonged hospitalization, exposure to antimicrobial therapy, and immunocompromised states such as human immunodeficiency virus infection. The emergence of MDRPA isolates during therapy was reported in 27%-72% of patients with initially susceptible P. aeruginosa isolates. Patients with severe MDRPA infections should be treated with combination therapy, consisting of an antipseudomonal β-lactam with an aminoglycoside or fluoroquinolone, rather than aminoglycoside and fluoroquinolone combinations, to provide adequate therapy and improve patient outcomes (1).P. aeruginosa produces a number of virulence factors, which, after colonization, can cause extensive tissue damage, bloodstream invasion, and dissemination (2). Pathogenesis is based on multiple virulence factors: endotoxin, exotoxins, and enzymes. Its endotoxin, like that of other gram-negative bacteria, causes the symptoms of sepsis and septic shock (3). Most strains of P. aeruginosa produce 2 exotoxins, exotoxin A and exoenzyme S; a variety of cytotoxic substances including phospholipases, pyocyanin, and proteases; and an alginate-like exopolysaccharide that is responsible for the mucoid phenotype. The importance of these putative virulence factors depends upon the site and nature of infection. Proteases play a key role in corneal ulceration, are important in burn infection, and are associated with chronic pulmonary colonization (4). Chitinase produced by P. aeruginosa has been investigated as a virulence factor associated with plant diseases (5). Folders et al. ( 6) reported that ChiC chitinase was produced by clinical isolates of P. aeruginosa. These virulence factors help the bacteria Background/aim: Virulent Pseudomonas aeruginosa is frequently life-threatening and often challenging to treat, and the emergence of multidrug-resistant isolates presents a critical problem for patients. The aim of the study was concerned with molecular analysis of the virulence factors and antimicrobial resistance profile of multidrug-resistant P. aeruginosa (MDRPA).Materials and methods: Out of 44 MDRPA isolates, 12 isolates representing different resistance profiles and sources of samples were selected for further molecular studies. Polymerase chain reaction (PCR) approaches were applied to identify the genes implicated in antimicrobial resistance or virulence factors in the selected MDRPA isolates.Results: Multidrug-resistance (pstS), β-lactamase (IMP7, IMP10, IMP13, and IMP25), and extended spectrum β-lactamase (blaOXA50) genes were detected in all of the selected MDRPA isolates. However, only 4 (33%) MDRPA isolates were positive for the presence of the extended spectrum β-lactamase (blaOXA2) gene. Furthermore, the hemolytic phospholipase C precursor gene (plcH) was detected in all PCR products of the tested MDRPA isolates while the exotoxin A (toxA) gene was ab...

<p>Virulence Factors Of Carbapenem-Resistant <em>Pseudomonas aeruginosa</em> In Hospital-Acquired Infections In Mansoura, Egypt</p>

“…Also, Rossi Goncalves23 concluded a high rate of MDR (73.9%). However, a lower rate of MDR was reported in other studies conducted in Egypt 24,25. This high rate of resistance among our isolates may be due to the fact that they were from hospital-acquired infections 26…”

“…The rate of imipenem resistance varies widely from 1% to 73.5% 12,16,23 – 25,27,28. In our study, the frequency of imipenem resistance in P. aeruginosa was 42.5%.…”

Ciprofloxacin, amoxicillin, and aminoglycosides stimulate genetic and phenotypic changes in uropathogenic Escherichia coli strains

“…The subsequent important stage of our study was to verify the extent to which the antibiotics are able to influence the virulence genes of the UPEC strains. It has been long observed that antibiotic resistance correlates with certain bacterial features, this correlation is especially observed between fluoroquinolones and bacterial virulence [27,28,34,[61][62][63][64][65][66][67]. In our study, the presence of six virulence factor gene regions (papC, sfaE/D, cnf1, usp, fimG/ H, hlyA) and their expression were analyzed.…”

Exposure to Sublethal Concentrations of Benzalkonium Chloride Induces Antimicrobial Resistance and Cellular Changes in Klebsiellae pneumoniae Clinical Isolates

“…1 Recently, multidrug-resistant bacteria have become more common and are causing problems in the treatment of infections. 2 It was found that the dissemination of resistance among bacteria has been attributed to inappropriate use of antimicrobials in hospitals and communities and failure among health care providers to comply with infection control precautions. 3 Klebsiella pneumoniae is an opportunistic pathogen that causes both hospital-acquired and community-acquired infections such as pneumonia, urinary tract infection, and pyogenic liver abscess.…”