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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
New antimicrobial agents as therapy for resistant gram-positive cocci
J R Lentino1, M Narita, V L Yu
1Section of Infectious Diseases, Loyola University Stritch School of Medicine, Edward Hines DVA Hospital, Hines DVA Medical Center, Division of Infectious Diseases, 2160 S First Ave, Maywood, IL 60153, USA. joseph.lentino@va.gov
Summary
Newer antibiotics like quinupristin/dalfopristin, linezolid, daptomycin, and tigecycline show promise against resistant gram-positive cocci. These agents offer improved efficacy and pharmacodynamic properties compared to vancomycin for challenging hospital-acquired infections.
Area of Science:
- Infectious Diseases
- Pharmacology
- Microbiology
Background:
- Hospital-acquired infections caused by vancomycin- and methicillin-resistant gram-positive cocci are a growing concern.
- Vancomycin, a traditional treatment, faces limitations due to emerging resistance.
- Novel therapeutic strategies are crucial to combat these resistant pathogens.
Purpose of the Study:
- To review newer antibiotics with demonstrated activity against vancomycin-resistant and methicillin-resistant gram-positive cocci.
- To compare the efficacy, pharmacologic properties, and safety profiles of these novel agents against vancomycin.
- To provide an overview of their antibacterial spectrum, clinical applications, and adverse events.
Main Methods:
- Literature review of scientific articles and clinical studies.
- Analysis of in vitro data, animal models, and clinical trial results.
- Synthesis of information on antibacterial spectrum, pharmacodynamics, pharmacokinetics, and clinical use.
Main Results:
- Quinupristin/dalfopristin, linezolid, daptomycin, and tigecycline exhibit in vitro activity against methicillin-resistant staphylococci and are superior to vancomycin for vancomycin-resistant isolates.
- Newer glycopeptides (dalbavancin, telavancin, oritavancin) offer improved pharmacodynamic properties over vancomycin.
- Specific agents show distinct advantages: daptomycin for S. aureus bacteremia/endocarditis, linezolid for MRSA pneumonia, quinupristin/dalfopristin for VRE (excluding E. faecalis), and tigecycline for mixed infections including Enterobacteriaceae and anaerobes.
Conclusions:
- Several newer antibiotics demonstrate significant activity and improved profiles compared to vancomycin for treating infections caused by resistant gram-positive cocci.
- These agents offer valuable therapeutic options with distinct indications and advantages for specific resistant pathogens.
- Further research and clinical application of these novel antibiotics are essential for managing challenging hospital-acquired infections.
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