Antimicrobial Therapy in Pseudomonas Aeruginosa Infections

Pseudomonas aeruginosa is an opportunistic Gram-negative pathogen notable for its intrinsic resistance mechanisms, including efflux pumps, inducible β-lactamases and biofilm formation. It causes a spectrum of nosocomial infections—ventilator-associated pneumonia, bloodstream infections and urinary tract infections—often in immunocompromised or critically ill patients. Traditional therapies have relied on antipseudomonal β-lactams, aminoglycosides and fluoroquinolones, but rising multidrug-resistance (MDR) and carbapenem-resistance threaten clinical efficacy. Recent advances include novel β-lactam/β-lactamase inhibitor combinations, siderophore cephalosporins and renewed interest in polymyxins. Current practice balances empiric broad-spectrum coverage with rapid de-escalation guided by susceptibility testing, supported by antimicrobial stewardship to preserve agent activity and limit toxicity.

Research from Nature Portfolio

Meta-analytic evidence has demonstrated that infections caused by carbapenem-resistant P. aeruginosa carry a significantly higher risk of mortality compared with carbapenem-susceptible strains. This synthesis quantified a more than twofold increase in crude and adjusted odds of death, across various sites of infection and patient cohorts. The findings underscore the clinical urgency of early resistance detection and judicious carbapenem use to improve survival outcomes.

Antimicrobial Therapy in Pseudomonas Aeruginosa Infections publication trend

The graph below shows the total number of articles in antimicrobial therapy in pseudomonas aeruginosa infections across all publications each year (not limited to Nature Index journals).

Technical terms

Carbapenem-resistant P. aeruginosa (CRPA): Strains exhibiting resistance to carbapenem antibiotics, often via enzyme production or porin loss.

Multidrug-resistant (MDR): Bacteria non-susceptible to at least one agent in three or more antimicrobial classes.

Extensively drug-resistant (XDR): Bacteria non-susceptible to all but one or two classes of agents, limiting treatment options.

Empiric therapy: Initiation of broad-spectrum antibiotics before pathogen identification and susceptibility results are available.

De-escalation: Narrowing antibiotic coverage based on microbiology and clinical response to minimise toxicity and resistance.

Biofilm: Structured bacterial community within an extracellular matrix that impedes antibiotic penetration and host defences.

References

1. Single-drug versus combination antimicrobial therapy in critically ill patients with hospital-acquired pneumonia and ventilator-associated pneumonia due to Gram-negative pathogens: a multicenter retrospective cohort study. Critical Care (2024).
2. Assessment of mortality-related risk factors and effective antimicrobial regimens for treatment of bloodstream infections caused by carbapenem-resistant Pseudomonas aeruginosa in patients with hematological diseases. Frontiers in Cellular and Infection Microbiology (2023).
3. Evidence-Based Treatment of Pseudomonas aeruginosa Infections: A Critical Reappraisal. Antibiotics (2023).
4. Influence of carbapenem resistance on mortality of patients with Pseudomonas aeruginosa infection: a meta-analysis. Scientific Reports (2015).