Treatment of Enterococcus faecalis Catheter-Associated Bloodstream Infection
For Enterococcus faecalis catheter-associated bloodstream infection (CRBSI), ampicillin is the drug of choice for ampicillin-susceptible isolates, with vancomycin reserved for ampicillin-resistant strains, and removal of infected short-term catheters is recommended. 1
Initial Management
- Remove infected short-term intravascular catheters 1
- For infected long-term catheters, removal is indicated in cases of:
- Insertion site or pocket infection
- Suppurative thrombophlebitis
- Sepsis
- Endocarditis
- Persistent bacteremia
- Metastatic infection 1
Antimicrobial Therapy
First-line options:
- Ampicillin-susceptible E. faecalis: Ampicillin is the drug of choice 1
- Ampicillin-resistant E. faecalis: Vancomycin should be used 1
- Ampicillin and vancomycin-resistant E. faecalis: Linezolid or daptomycin based on susceptibility results 1
Dosing considerations for resistant strains:
- For vancomycin-resistant enterococci in dialysis patients: daptomycin 6 mg/kg after each dialysis session or oral linezolid 600 mg every 12 hours 1
- Higher daptomycin doses (≥9 mg/kg) have shown more rapid bacterial clearance than conventional doses (6-9 mg/kg) 2
- Recent evidence suggests doses ≥11 mg/kg may improve survival in vancomycin-resistant enterococcal bloodstream infections, particularly for isolates with higher MICs 3
Duration of Therapy
- 7-14 days for uncomplicated enterococcal CRBSI when:
- Extended therapy (4-6 weeks) for complicated cases with:
- Endocarditis
- Suppurative thrombophlebitis
- Persistent bacteremia 1
Adjunctive Therapy
- If long-term catheter is retained, antibiotic lock therapy should be used in addition to systemic therapy 1
- For patients with retained catheters, obtain follow-up blood cultures and remove catheter if bacteremia persists >72 hours after initiating appropriate antibiotics 1
Monitoring for Complications
- Perform transesophageal echocardiography (TEE) if:
- Signs/symptoms suggest endocarditis (new murmur, embolic phenomena)
- Prolonged bacteremia or fever despite appropriate therapy (>72 hours)
- Radiographic evidence of septic pulmonary emboli
- Presence of prosthetic valve or other endovascular foreign bodies 1
Role of Combination Therapy
- The role of combination therapy (cell wall-active agent plus aminoglycoside) for enterococcal CRBSI without endocarditis remains unresolved 1
- Some evidence suggests combination therapy with gentamicin and ampicillin may be more effective than monotherapy when catheter is retained 1
- Alternative combination: ampicillin plus high-dose ceftriaxone has been used successfully when aminoglycosides cannot be used due to resistance or nephrotoxicity 1
Special Considerations
- Enterococcal bacteremia persisting >4 days is independently associated with increased mortality 1
- Monitor for creatine kinase elevation with high-dose daptomycin therapy; higher rates of elevation (>2000 U/L) have been reported with doses ≥11 mg/kg (3.9%) compared to 8-<11 mg/kg (1.1%) 3
- EUCAST has noted insufficient evidence for daptomycin breakpoints for Enterococcus species, recommending increased vigilance when using high-dose daptomycin 5