Resistance mechanisms, control strategies and outbreak management in Klebsiella pneumoniae

Abstract

Klebsiella (K.) pneumoniae is a major reason of multidrug-resistant infections worldwide. The Enterobacterales that produce β-lactamases represent significant sources of infections within healthcare environments. This prevalence can be attributed to the challenges they pose in treatment, their high potential for transmission, and their substantial economic and personal impact. Recent studies highlight the emergence of multidrug-resistant K. pneumoniae strains which show resistance to colistin, a last-line antibiotic, arising from mutational inactivation of the mgrB regulatory gene. The bacteria of greatest clinical relevance are those with resistance to third and fourth generation cephalosporins, extended spectrum β-lactamases and ampicillin-cephalosporin. Carbapenems represent a category of antibiotics that remain one of the limited options for addressing infections caused by multi-drug resistant pathogens. Typically, these antibiotics are reserved as a final solution when other therapies prove ineffective. Nevertheless, the rising prevalence of carbapenem-resistant bacteria presents a considerable obstacle to their efficacy. Continuous monitoring and the advancement of alternative therapeutic strategies are essential to tackle the escalating challenge of antibiotic resistance. However, the rise of carbapenem-resistant Enterobacterales poses significant health challenges. Notably, K. pneumoniae, a pan-resistant bacterium, is associated with high morbidity rates, particularly in public health settings. This study reviews the various aspects of antibacterial resistance, focusing on the genes present in the genome of K. pneumoniae and the mechanisms through which it develops resistance. Through the analysis of these factors, we intend to highlight the escalating threat posed by antibiotic resistance and the urgent requirement for effective measures to counteract it. Surveillance and diagnostics are vital for controlling outbreaks as they enable early detection of diseases, allowing for timely interventions to prevent further spread. Accurate laboratory diagnostics are essential for confirming cases and informing public health responses, thereby ensuring the effective allocation of resources during an outbreak. In this work, we have carried out a review on the antibacterial resistance antibiotics, genes found in its genome, as well as the resistance mechanisms involved. Finally, we focus on the main outbreaks causing hospital acquired infections during the last few years.

Keywords

Klebsiella pneumoniae / Antibiotic resistance / Carbapenem resistance / Resistance mechanisms

Conflict of interest statement

The authors claim there is no conflict of interest.

Acknowledgements

The authors sincerely acknowledge the support of the Dean Research, CT University, for their invaluable guidance. Special thanks are extended to the Chancellor Sir, Vice Chancellor Sir and Dean Academics Mam of CT University for their encouragement and support, which greatly contributed to the successful completion of this work.

Funding

The study receives no extramural funding.

Data availability statement

The data supporting the findings of this study are available from the corresponding author upon request.

Authors’ contributions

Verma G conceptualized the review, interpreted the literature. Verma G and Sharma B contributed to the writing, critical review, and editing of the manuscript to ensure clarity, coherence, and scholarly rigor. All authors reviewed and approved the final version of the manuscript.

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