Current use for old antibacterial agents: polymyxins, rifamycins, and aminoglycosides

Area of Science:

• Pharmacology
• Infectious Diseases
• Antimicrobial Agents

Background:

• Standard antibiotics are often ineffective against certain resistant bacterial infections.
• Specialized antimicrobial agents are crucial for treating complex and refractory cases.
• Understanding the niche applications of less common antibiotics is vital for effective treatment strategies.

Purpose of the Study:

• To review three classes of antibacterial agents that are uncommonly used.
• To highlight the specific applications and potential of polymyxins, rifamycins (rifampin and rifaximin), and aminoglycosides.
• To inform clinicians about the strategic use of these special-use agents in challenging bacterial infections.

Main Methods:

• Literature review of polymyxins, rifampin, rifaximin, and aminoglycosides.
• Analysis of current therapeutic guidelines and clinical evidence for these agents.
• Synthesis of information on their mechanisms, spectrum of activity, and clinical indications.

Main Results:

• Polymyxins are reserved for multidrug-resistant Gram-negative bacilli.
• Rifampin is a companion drug for refractory Gram-positive coccal infections, particularly with foreign bodies.
• Rifaximin shows promise for traveler's diarrhea and refractory Clostridium difficile infections.
• Aminoglycosides are primarily used as companion drugs for resistant Gram-negative infections and Gram-positive coccal endocarditis.

Conclusions:

• Special-use antibacterial agents like polymyxins, rifamycins, and aminoglycosides play critical roles in managing resistant and refractory infections.
• Rifaximin represents a novel therapeutic option for specific enteric and Clostridium difficile infections.
• Strategic deployment of these agents is essential for optimizing patient outcomes in challenging infectious disease scenarios.