From the Guidelines
Augmentin (amoxicillin-clavulanate) is not effective against Vancomycin-Resistant Enterococci (VRE) infections and should not be used for this purpose. VRE is resistant to many antibiotics, including penicillins like amoxicillin, even when combined with beta-lactamase inhibitors like clavulanic acid in Augmentin. For VRE infections, appropriate treatment options include linezolid (600 mg IV/PO twice daily), daptomycin (6-12 mg/kg IV once daily), or tigecycline (100 mg IV loading dose followed by 50 mg IV twice daily) 1. In some cases, quinupristin-dalfopristin or newer agents like tedizolid may be considered. The choice depends on the infection site, severity, and susceptibility testing. VRE has acquired genetic elements that alter cell wall precursors, preventing vancomycin binding, and these modifications also confer resistance to beta-lactams like those in Augmentin.
Key Considerations
- Treatment should be guided by antimicrobial susceptibility testing and infectious disease consultation is recommended for managing VRE infections due to their complex resistance patterns.
- High dose daptomycin (8-12 mg/kg IV daily) may be used to treat VRE bloodstream infections, and combination antimicrobial therapy may be considered in severely ill patients or those who fail treatment with traditional options 1.
- Tigecycline is recommended for intra-abdominal infections caused by VRE, and fosfomycin or nitrofurantoin may be used for uncomplicated urinary tract infections due to VRE 1.
Treatment Options
- Linezolid: 600 mg IV/PO twice daily
- Daptomycin: 6-12 mg/kg IV once daily
- Tigecycline: 100 mg IV loading dose followed by 50 mg IV twice daily
- Fosfomycin: 3 g PO x 1 dose or 3 g PO qod
- Nitrofurantoin: 100 mg PO qid
- Ampicillin: 18-30 g/day IV in divided doses
- Amoxicillin: 500 mg PO/IV q8h It is essential to note that the treatment duration should be individualized according to infection sites, source control, the underlying comorbidities, and the initial response to therapy 1.
From the Research
Effectiveness of Augmentin against Vancomycin-Resistant Enterococci (VRE)
- There is no direct evidence in the provided studies to suggest that Augmentin (amoxicillin-clavulanate) is effective against Vancomycin-Resistant Enterococci (VRE) 2, 3, 4, 5, 6.
- The studies discuss various treatment options for VRE infections, including linezolid, quinupristin/dalfopristin, daptomycin, and tigecycline, but do not mention Augmentin as a treatment option for VRE 2, 3, 4, 5, 6.
- Aminopenicillins, such as ampicillin, are mentioned as preferred agents when enterococci are susceptible, but this does not necessarily imply that Augmentin, which is a combination of amoxicillin and clavulanate, is effective against VRE 2.
- The studies emphasize the importance of appropriate use of available agents and the need for careful clinical interpretation of cultures that grow enterococci to avoid unnecessary and potentially deleterious antimicrobial therapy 2, 3, 4, 5, 6.
Alternative Treatment Options for VRE
- Linezolid, an oxazolidinone compound, has been shown to have bacteriostatic activity against both vancomycin-resistant E. faecium and E. faecalis 5.
- Quinupristin/dalfopristin, a streptogramin, has been approved for the treatment of vancomycin-resistant Enterococcus faecium, but its use is limited by its bacteriostatic activity and potential for resistance 5.
- Daptomycin, an acidic lipopeptide, has been shown to have clinical efficacy against VRE, but its use is often limited to complicated infections 3, 5, 6.
- Newer agents, such as tedizolid, oritavancin, and eravacycline, are being developed and may offer alternative treatment options for VRE infections 6.