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Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method
Published on: April 18, 2019
Polymyxin antibiotics for gram-negative infections
Tamra M Arnold1, Graeme N Forrest, Karen J Messmer
1Richard L. Roudebush Veterans Affairs Medical Center (VAMC), Indianapolis, IN 46202, and School of Medicine, University of Maryland, Baltimore, USA. tamra.arnold@va.gov
Summary
Polymyxin antibiotics are effective against multidrug-resistant gram-negative infections, offering a last resort option. Recent data suggest lower toxicity than previously reported, making them a viable treatment choice when necessary.
Area of Science:
- Microbiology
- Infectious Diseases
- Pharmacology
Background:
- Antimicrobial resistance is a growing global health crisis, particularly in hospital settings.
- Polymyxins, derived from Bacillus species, are effective against Gram-negative bacteria due to their detergent-like action.
- Historically, polymyxins were associated with significant nephrotoxicity and neurotoxicity, limiting their use.
Purpose of the Study:
- To review the role of polymyxin antibiotics in treating multidrug-resistant Gram-negative infections.
- To assess the current understanding of polymyxin efficacy and toxicity.
Main Methods:
- Literature review of clinical trials and studies on polymyxin antibiotics.
- Analysis of historical and recent data on polymyxin usage, effectiveness, and adverse events.
Main Results:
- Emergence of multidrug-resistant Gram-negative organisms has led to increased polymyxin use.
- Recent studies indicate that polymyxin-associated nephrotoxicity and neurotoxicity may be less frequent and severe than previously believed.
- Clinical trials demonstrate acceptable effectiveness of polymyxins for treating multidrug-resistant Gram-negative infections.
Conclusions:
- Polymyxins are a crucial last-resort treatment for infections caused by multidrug-resistant Gram-negative bacteria.
- While effective, polymyxins should not be considered first-line therapy until further research clarifies their safety profile.
- The reevaluation of polymyxin toxicity suggests a more favorable risk-benefit ratio in specific clinical scenarios.
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