Treatment Options for Enterococcus Bacteremia

First-Line Treatment Options

The Infectious Diseases Society of America recommends ampicillin 2g IV every 6 hours as the preferred treatment for ampicillin-susceptible enterococci 1
For patients with beta-lactam allergy, vancomycin is an appropriate alternative, as suggested by the Clinical Infectious Diseases guidelines 1
The American College of Physicians recommends treatment duration of 7-14 days for uncomplicated bacteremia if source control is achieved, with a strength of evidence rated as high 2

The Centers for Disease Control and Prevention strongly recommend catheter removal for enterococcal catheter-related bloodstream infections (CRBSI), especially for short-term catheters, with a strength of evidence rated as strong 1
The Society for Healthcare Epidemiology of America recommends antibiotic lock therapy in addition to systemic therapy if a long-term catheter cannot be removed, with a strength of evidence rated as moderate 1

The American Heart Association recommends transesophageal echocardiography (TEE) if the patient has signs and symptoms suggesting endocarditis, with a strength of evidence rated as high 1
The Infectious Diseases Society of America recommends TEE for patients with prolonged bacteremia or fever (>72 hours) despite appropriate antimicrobial therapy, with a strength of evidence rated as moderate 1

The American College of Physicians recommends treatment duration of 7-14 days for uncomplicated bacteremia with source control, with a strength of evidence rated as high 2
The Infectious Diseases Society of America recommends treatment duration of at least 6 weeks for complicated bacteremia or endocarditis, with a strength of evidence rated as moderate 2

The European Society of Clinical Microbiology and Infectious Diseases recommends combination approaches, including high-dose daptomycin plus ampicillin or ceftaroline, for strains resistant to standard therapies, with a strength of evidence rated as low 2
The Clinical Infectious Diseases guidelines suggest chloramphenicol as a salvage option for VRE bloodstream infections, with reported clinical response rates of 61%, and a strength of evidence rated as low 1

The American College of Physicians recommends obtaining follow-up blood cultures to document clearance of bacteremia, with a strength of evidence rated as high 2
The Clinical Infectious Diseases guidelines recommend monitoring complete blood counts weekly for patients receiving linezolid due to risk of bone marrow suppression, with a strength of evidence rated as moderate 2
The European Society of Clinical Microbiology and Infectious Diseases recommends monitoring creatine phosphokinase levels weekly for daptomycin therapy, with a strength of evidence rated as moderate 2

The Infectious Diseases Society of America warns that cephalosporins and aminoglycosides as monotherapy are ineffective against enterococci, leading to high rates of inefficient empirical therapy, with a strength of evidence rated as high 2
The American College of Physicians advises that standard doses of daptomycin (6 mg/kg/day) are inadequate for treating resistant E. faecium; higher doses (10-12 mg/kg/day) are required, with a strength of evidence rated as high 2
The Clinical Infectious Diseases guidelines note that daptomycin monotherapy has been associated with treatment failures and development of resistance during therapy, with a strength of evidence rated as moderate 2
The Centers for Disease Control and Prevention emphasize that failure to remove infected devices or achieve source control will likely result in treatment failure, with a strength of evidence rated as high 2

The Infectious Diseases Society of America recommends linezolid for bacteremia caused by vancomycin-resistant Enterococcus faecium (VRE) or as an alternative to vancomycin for MRSA bacteremia when first-line agents have failed or cannot be used 3, 4

For vancomycin-resistant Enterococcal bacteremia, linezolid 600 mg IV or PO every 12 hours is the recommended treatment 5
For MRSA catheter-related bloodstream infections (CRBSI), linezolid showed comparable outcomes to vancomycin: 81% microbiological cure for linezolid vs. 86% for vancomycin (95% CI, −26 to 16) 3, 4
For methicillin-susceptible S. aureus CRBSI, outcomes were also equivalent: 82% cure for linezolid vs. 83% for vancomycin 3, 4
However, patients without confirmed bacteremia at baseline had worse survival with linezolid compared to vancomycin (HR 2.20; 95% CI, 1.07–4.50) 3, 4

Linezolid achieves excellent tissue penetration, particularly in lung epithelial lining fluid, making it suitable for pneumonia with concurrent bacteremia 6
In a meta-analysis of 3,067 patients with VRE bacteremia, linezolid showed lower crude mortality compared to daptomycin (32.8% vs. 35.7%, RR 1.24; 95% CI, 1.02-1.50) 7

Do not use linezolid for empirical therapy when bacteremia is suspected but not confirmed 3, 4
Do not use linezolid for Gram-negative bacteremia—there was no survival benefit and potentially worse outcomes (HR 1.94; 95% CI, 0.78–4.81) 3, 4
Avoid linezolid in patients without documented bacteremia who have catheter-related infections, as mortality was significantly higher with linezolid (HR 2.20) 3, 4

The Infectious Diseases Society of America recommends linezolid as an alternative to vancomycin for MRSA nosocomial pneumonia with concurrent bacteremia, with clinical response rates of 57.6% vs. 46.6% (p = 0.042) 8
For healthcare-associated infections, consider MRSA coverage in severe cases, such as patients on chronic hemodialysis, with chronic wounds, indwelling catheters, or those in long-term care facilities, and use local institutional epidemiology to guide empirical anti-MRSA therapy decisions 8
The American Thoracic Society suggests that linezolid achieves excellent tissue penetration in lung epithelial lining fluid, making it suitable for pneumonia with concurrent bacteremia, and no therapeutic drug monitoring is required unlike vancomycin 8