Insights into the Evolution of P. aeruginosa Antimicrobial Resistance in a Patient Undergoing Intensive Therapy

Factors associated with multidrug-resistant organism (MDRO) mortality: an analysis from the national surveillance of multidrug-resistant organism, 2018-2022

INTRODUCTION

Antimicrobial resistance is a global issue, with the World Health Organization identifying it as one of the greatest threats to public health, with an estimated 4.95 million deaths linked to bacterial AMR in 2019. Our study aimed to determine the prevalence of mortality among multidrug-resistant organism (MDRO)-infected patients in state hospitals and major specialist hospitals and to identify risk factors that could be associated with mortality outcomes.

METHODS

This is a cross-sectional study performed at 28 hospitals under the Ministry of Health, Malaysia, involved in the National Surveillance of Multidrug-Resistant Organism, which surveys 6 MDROs (Acinetobacter baumanii, extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli, extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae, carbapenem-resistant Entrobacterales (CRE), methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE)).

RESULTS

In terms of mortality, 9.6% (n = 951) of the patients died overall, whereas 90.4% (n = 8931) of the patients survived. Healthcare-acquired infection (HCAI) poses a high risk of mortality, with an adjusted odds ratio (aOR) of 2.91 (95% CI: 2.15-3.94). The presence of sterile specimens was significantly associated with increased mortality risk (aOR: 2.33, 95% CI: 2.02-2.68). Gram-negative bacteria had a greater mortality risk (aOR 1.63 95% CI: 1.37-1.93), whereas Acinetobacter baumanii had the highest prevalence of 30.7% (3033) among the 6 MDRO organisms isolated. Patients in medical-based departments had a greater mortality risk (aOR: 1.47, 95% CI: 1.22-1.75).

CONCLUSION

HCAIs, Gram-negative bacteria, sterile specimens, medical-based departments and state hospitals have been shown to be associated with increased mortality risk in patients with MDRO infections. Improved surveillance and reporting mechanisms are necessary to better understand the burden of MDRO infections and guide research funding allocation.

Mitigating Health Risks Through Environmental Tracking of Pseudomonas aeruginosa

Pseudomonas aeruginosa is a prevalent nosocomial pathogen and a significant reservoir of antimicrobial resistance genes in residential and built environments. It is also widespread in various indoor and outdoor settings, including sewage, surface waters, soil, recreational waters (both treated and untreated), and industrial effluents. Surveillance efforts for P. aeruginosa are primarily focused on hospitals rather than built environments. However, evidence links multidrug-resistant P. aeruginosa of human origin with activity in built environments and hospital settings. Consequently, tracking this pathogen across all environments is crucial for understanding the mechanisms of reverse transmission from built environments to humans. This review explores public health hygiene by examining the prevalence of P. aeruginosa in various environments, its sequence types, the factors contributing to multidrug resistance, and the identification methods through global surveillance. Whole-genome sequencing with sequence typing and real-time quantitative PCR are widely used to identify and study antimicrobial-resistant strains worldwide. Additionally, advanced techniques such as functional metagenomics, next-generation sequencing, MALDI-TOF, and biosensors are being extensively employed to detect antimicrobial-resistant strains and mitigate the ongoing evolution of bacterial resistance to antibiotics. Our review strongly underscores the importance of environmental monitoring of P. aeruginosa in preventing human infections. Furthermore, strategic planning in built environments is essential for effective epidemiological surveillance of P. aeruginosa and the development of comprehensive risk assessment models.

Genomic and metabolic versatility of Pseudomonas aeruginosa contributes to its inter-kingdom transmission and survival

Pseudomonas aeruginosa is one of the most versatile bacteria with renowned pathogenicity and extensive drug resistance. The diverse habitats of this bacterium include fresh, saline and drainage waters, soil, moist surfaces, taps, showerheads, pipelines, medical implants, nematodes, insects, plants, animals, birds and humans. The arsenal of virulence factors produced by P. aeruginosa includes pyocyanin, rhamnolipids, siderophores, lytic enzymes, toxins and polysaccharides. All these virulent elements coupled with intrinsic, adaptive and acquired antibiotic resistance facilitate persistent colonization and lethal infections in different hosts. To date, treating pulmonary diseases remains complicated due to the chronic secondary infections triggered by hospital-acquired P. aeruginosa. On the contrary, this bacterium can improve plant growth by suppressing phytopathogens and insects. Notably, P. aeruginosa is one of the very few bacteria capable of trans-kingdom transmission and infection. Transfer of P. aeruginosa strains from plant materials to hospital wards, animals to humans, and humans to their pets occurs relatively often. Recently, we have identified that plant-associated P. aeruginosa strains could be pathologically similar to clinical isolates. In this review, we have highlighted the genomic and metabolic factors that facilitate the dominance of P. aeruginosa across different biological kingdoms and the varying roles of this bacterium in plant and human health.