Pseudomonas aeruginosa (PA) has emerged as a significant cause of Gram-negative infections, particularly in patients with impaired host defenses. It is one of the six ESKAPE pathogens that majorly cause severe nosocomial infections. In addition to biofilm formation, PA possesses various virulence factors. It can be life-threatening due to his remarkable capacity to resist antibiotics, either intrinsically, developing adaptative resistance, or following the acquisition of resistance genes. The situation worsens when these mechanisms co-exist, conferring worrying multi-resistant phenotypes. Therapeutic options are becoming limited, which has led to the development of new antibiotics and novel alternative therapeutic strategies that require the exploration of other therapeutic avenues. Although mostly at the preclinical stages, many recent studies have reported several innovative therapeutic technologies that have demonstrated pronounced effectiveness in fighting against drug-resistant Pa strains. This literature review aims to discuss the mechanism of pyocyanic bacillus resistance to antibiotics, highlight the current state of some novel antibiotics and combination therapies, and the new alternative therapeutic approaches for treating PA infections.

Pseudomonas aeruginosa (Pa) remains among clinically-significant Gram-negative species. The carbapenems are often the last resort for treating infections due to multidrug resistant isolates such as Pa. The carbapenems' efficacy is increasingly compromised by the emergence and the rapid spread of Pa carrying carbapenemases which represent a serious threat to public health. This study aimed to establish the resistance profile and to identify carbapenemase genes in isolates with imipenem resistant phenotypes. Among 134 Pa isolates collected both in the community (46) and hospital (88) from January 2021 to December 2021 in Morocco, 18 (8 were from the community and 10 from the hospital settings) were carbapenem resistant. The identification of these strains has been confirmed using matrix assisted laser desorption ionization-time of flight (MALDI-TOF). The antibiotic susceptibility testing against 16 antibiotics was carried out and interpreted according to the recommendations of the European Committee on Antimicrobial Susceptibility Testing (2021). The worrying antibiotics resistance profiles, which spread to cefiderocol for two isolates, were obtained for all isolates, which were eXtensive Drug Resistance showing highly resistant to all antibiotic categories tested, even to ceftolozane–tazobactam. Colistin (100% susceptible) and cefiderocol (88.88%) were the most active agents against carbapenem-resistant Pa (CRPa). Phenotypic detection by NP-CARBA and NG-CARBA tests of metallo‑β‑lactamase (MβL) production was confirmed by PCR amplification and sequencing. Three CRPa isolates coharboring bla _VIM-2 - bla _NDM-1 (two isolates) and bla _VIM-2 - bla _IMP-8 (one isolate) genes were detected. In this study, we describe the coexistence of these MβL genes and the cefiderocol resistance in CRPa strains in Morocco. The alarming antibiotic resistance patterns of all these CRPa isolates and their resistance genes emphasize the importance of antimicrobial susceptibility testing in the choice of antibiotics for treating Pa infections.

The spread of high-risk extensively drug-resistant (XDR) Pseudomonas aeruginosa (Pa) clones is a global threat to public health. In Morocco, data on circulating clones and genomic features of Pa isolates are lacking. Accordingly, this study performed whole-genome sequencing (Illumina NextSeq500) of 18 Pa isolates from hospitals (n = 10) and the community (n = 8) to identify their sequence type (ST) affiliation, antimicrobial resistance determinants, virulence factors, and phylogenetic relationships. Isolates were selected based on alarming resistance profiles from strains collected in Casablanca, Morocco, between January and December 2021. These isolates were assigned sequence type 773 (n = 11), 308 (n = 5), and 233 (n = 1), in addition to a novel ST4902 for one hospital isolate. Carbapenem resistance in hospital isolates was primarily attributed to acquired carbapenemases (NDM-1 in ST773 and ST308 clones). In contrast, resistance in one hospital (CSPa93) and one community isolate (cSPa43) was associated with mutations in the outer membrane protein. Fluoroquinolone resistance correlated with the carriage of qnrVC1 and crpP genes, along with mutations in the quinolone resistance-determining regions. The isolates also carried diverse aminoglycoside modifying enzymes and 16S rRNA methyltransferase genes. Genomic analysis also identified multiple virulence genes in these isolates, notably exoU in ST308 and ST773 isolates. Phylogenetic analysis further revealed hospital-adapted strains being genetically related to each other and to community strains. This first genomic investigation of circulating XDR Pa clones in both hospital and community settings in Morocco using whole-genome sequencing highlights the urgent need for enhanced surveillance and targeted strategies to contain the spread of XDR high-risk clones.

Pseudomonas aeruginosa is an important opportunistic pathogen increasingly associated with multidrug resistance (MDR) and therapeutic failure. Data on MDR community-associated P. aeruginosa in southern Morocco remain limited. This study evaluated the contribution of urban diagnostic laboratories to the surveillance of MDR P. aeruginosa in this underrepresented region. A retrospective multicenter study was conducted between January and December 2024 using data collected from urban medical diagnostic laboratories in southern Morocco. Clinical isolates of P. aeruginosa recovered from community-associated patients were identified using standard microbiological methods, and antimicrobial susceptibility testing was performed according to EUCAST guidelines. MDR was defined as non-susceptibility to at least one agent in three or more antimicrobial classes according to the international criteria. Associations between MDR status and demographic variables were assessed using Chi-square and Fisher’s exact tests, with statistical significance set at p < 0.05. Among the 49 P. aeruginosa isolates included, 29 (59.2%, 95% CI: 45.4–72.0%) were classified as MDR. High resistance rates were observed for several β-lactams, whereas most isolates remained susceptible to amikacin and selected β-lactam/β-lactamase inhibitor combinations. No statistically significant association was found between MDR status and demographic variables. These findings highlight the circulation of MDR P. aeruginosa in southern Morocco and suggest that urban diagnostic laboratories may provide valuable complementary data for community-level antimicrobial resistance surveillance.

The Journal of Public Health in Africa (JPHiA) is a peer-reviewed, academic journal that focuses on health issues in the African continent. The journal editors seek high quality original articles on public health related issues, reviews, comments and more. The aim of the journal is to move public health discourse from the background to the forefront. The success of Africa’s struggle against disease depends on public health approaches.