Treatment of Panresistant Enterococcus faecium Bacteremia
For panresistant Enterococcus faecium bacteremia, high-dose daptomycin (10-12 mg/kg/day) in combination with ampicillin or ceftaroline is recommended as the most effective treatment approach. 1
First-line Treatment Options
- High-dose daptomycin (10-12 mg/kg/day IV) should be used as the backbone of therapy for panresistant E. faecium bacteremia 1
- Combination therapy with daptomycin plus ampicillin or ceftaroline is strongly recommended, especially for persistent bacteremia or strains with high MICs to daptomycin within the susceptible range 1
- For patients unable to tolerate daptomycin, linezolid 600 mg IV or orally every 12 hours is an alternative option 1, 2
Treatment Algorithm Based on Clinical Scenario
For Uncomplicated Bacteremia:
- Start with high-dose daptomycin (10-12 mg/kg/day) plus ampicillin or ceftaroline 1
- Treatment duration should be 7-14 days if catheter-related and removed, or if source control is achieved 1
- Follow-up blood cultures should be obtained to document clearance of bacteremia 1
For Complicated Bacteremia or Endocarditis:
- High-dose daptomycin (10-12 mg/kg/day) plus ampicillin or ceftaroline for at least 6 weeks 1
- Obtain transesophageal echocardiography (TEE) if signs/symptoms of endocarditis are present, bacteremia persists >72 hours despite appropriate therapy, or if the patient has prosthetic valves or other endovascular foreign bodies 1
- Source control is critical, including removal of infected catheters or devices 1
Special Considerations
- Patients with panresistant E. faecium infections should be managed by a multidisciplinary team including specialists in infectious diseases, cardiology, cardiovascular surgery, and clinical pharmacy 1
- For catheter-related infections, removal of infected catheters is strongly recommended, especially for short-term catheters 1
- For long-term catheters that cannot be removed, antibiotic lock therapy should be used in addition to systemic therapy 1
- Persistent bacteremia (>72 hours despite appropriate therapy) should prompt removal of any retained catheters and evaluation for endocarditis or metastatic foci of infection 1
Alternative Treatment Options
- Linezolid 600 mg IV or orally every 12 hours may be used if daptomycin cannot be used, but be aware of potential bone marrow suppression and neuropathy with prolonged use 1
- Tigecycline 100 mg IV loading dose followed by 50 mg IV every 12 hours may be considered for intra-abdominal infections due to VRE 1
- For urinary tract infections specifically, options include fosfomycin 3 g PO (single dose), nitrofurantoin 100 mg PO every 6 hours, or high-dose ampicillin (18-30 g IV daily in divided doses) 1
Monitoring and Follow-up
- Obtain follow-up blood cultures to document clearance of bacteremia 1
- Monitor for development of resistance during therapy, especially with daptomycin 1
- For daptomycin therapy, monitor creatine phosphokinase (CPK) levels weekly 3
- For linezolid therapy, monitor complete blood counts weekly due to risk of bone marrow suppression 1, 2
Pitfalls and Caveats
- Daptomycin monotherapy has been associated with treatment failures and development of resistance during therapy 1
- Standard doses of daptomycin (6 mg/kg/day) are inadequate for treating panresistant E. faecium; higher doses (10-12 mg/kg/day) are required 1
- Combination therapy with daptomycin and a β-lactam (ampicillin or ceftaroline) shows synergistic activity in vitro and may prevent the emergence of resistance 1
- Linezolid is bacteriostatic against enterococci, which may limit its effectiveness in endovascular infections 1
- Source control is critical for successful treatment; failure to remove infected devices or drain abscesses will likely result in treatment failure 1