Management of Gram-Positive Cocci in Chains Bacteremia

Initial Assessment and Empiric Therapy

The Infectious Diseases Society of America recommends obtaining at least two sets of blood cultures before initiating antimicrobial therapy to establish the diagnosis and guide treatment 1
For empiric coverage of gram-positive cocci in chains, the American College of Physicians suggests selecting therapy based on local resistance patterns and patient risk factors, with vancomycin as an option for suspected methicillin-resistant strains 1, 2
For beta-lactam-susceptible strains, penicillin G remains the drug of choice with cefazolin as an alternative, according to the Clinical Infectious Diseases guidelines 2
If the patient is critically ill, has sepsis, or is neutropenic, the Infectious Diseases Society of America recommends considering combination therapy with an agent effective against gram-negative bacilli 3

For vancomycin-susceptible Enterococcus faecalis, the Infectious Diseases Society of America suggests ampicillin or penicillin plus gentamicin for synergy in complicated cases 3
For vancomycin-resistant enterococci, the Clinical Infectious Diseases guidelines recommend linezolid or daptomycin 4
For enterococcal bloodstream infections, combination therapy with ampicillin and gentamicin may be more effective than monotherapy when the catheter is retained, according to the Infectious Diseases Society of America 3

The Clinical Infectious Diseases guidelines recommend obtaining blood cultures from both the catheter and peripherally to measure differential time to positivity (DTTP) 5
A DTTP of ≥2 hours is highly sensitive and specific for catheter-related bacteremia, according to the Annals of Oncology 5
Long-term catheters should be removed in patients with severe sepsis, suppurative thrombophlebitis, endocarditis, or persistent bacteremia despite >72 hours of appropriate antimicrobial therapy, as recommended by the Infectious Diseases Society of America 1, 3

For uncomplicated bacteremia with source control, the Praxis Medical Insights guidelines recommend 7-14 days of therapy 4
For complicated infections, the Clinical Infectious Diseases guidelines suggest 4-6 weeks of therapy 1
When denoting duration of antimicrobial therapy, day 1 is the first day on which negative blood culture results are obtained, according to the Infectious Diseases Society of America 1

For patients with renal impairment, the Praxis Medical Insights guidelines recommend adjusting dosing of vancomycin and other renally cleared antibiotics 4
For hemodialysis patients, vancomycin can be dosed after each dialysis session, according to the Praxis Medical Insights guidelines 4
The Infectious Diseases Society of America recommends considering antibiotic lock therapy for catheter salvage in appropriate cases 1
The Praxis Medical Insights guidelines suggest monitoring vancomycin levels in patients with impaired renal function to avoid toxicity 2

Using vancomycin empirically when not indicated contributes to development of resistance, according to the Praxis Medical Insights guidelines 2
Continuing vancomycin when cultures are negative for beta-lactam-resistant organisms is not recommended by the Praxis Medical Insights guidelines 2
Delaying appropriate therapy for severe infections increases mortality, as noted by the Praxis Medical Insights guidelines 2
Using linezolid for empirical therapy in patients suspected but not proven to have bacteremia is not recommended by the Clinical Infectious Diseases guidelines 1