Virulence Factors and Resistance Determinants of Carbapenem Non-Susceptible Nosocomial Infections Caused by Pseudomonas aeruginosa

Abstract: According to the WHO, the rod-shaped, Gram-negative bacteria Pseudomonas aeruginosa continues to hold a prominent position as an antibiotic-resistant priority pathogen. It is an opportunistic pathogen that is very prevalent in hospital settings and causes nosocomial infections in immunocompromised individuals. The bacterium has a large genome with nearly 6000 genes that offer high adaptability and are connected to metabolic functions, virulence factors, transport efflux, and chemotherapy and resistance to multiple antibiotic classes, particularly β- lactams, cephalosporins, and carbapenems, which is on the rise in worldwide isolates. The wide range of virulence factors available to the pathogen allows it to be flexible and adaptable, allowing P. aeruginosa to customise its response to many environmental stressors. Prolonged durations of selection pressure, along with extensive antibiotic treatment, result in broad adaptive and acquired resistance in P. aeruginosa. Due to the predominance of MDR strains, alternative and novel antimicrobial therapies are considered to be effective treatments for multidrug-resistant infections, such as hospital-acquired pneumonia, urinary tract infections, wounds, surgical sites, and infections in malignant cells. Targeting certain resistance mechanisms, many strategies and initiatives have been used to counteract the growing prevalence of antibiotic resistance. Enhanced efflux pump action, porin modification in the outer membrane, enzymes that inactivate or modify antibiotics, and alterations to antibiotic target sites are among these mechanisms. This review discusses the many virulence characteristics of Pseudomonas aeruginosa hospitalacquired infections as well as new treatment options, with a particular focus on carbapenemresistant Pseudomonas aeruginosa. These advances could provide an alternative strategy for utilising combination therapy to improve the lifespan of resistant antimicrobials, as well as an outline of their efficacy in overcoming multidrug resistance for controlling Pseudomonas aeruginosa infections.