Management of Positive Blood Culture for Gram-Positive Cocci in Afebrile Patients with Normal WBC

Initial Assessment and Management

The American College of Physicians recommends that positive blood cultures for gram-positive cocci represent true bacteremia until proven otherwise, requiring prompt antibiotic therapy regardless of the absence of fever or normal WBC count 1
The Infectious Diseases Society of America suggests collecting at least one additional set of blood cultures from peripheral sites to confirm the initial finding and rule out contamination before initiating antibiotics if the patient is clinically stable 3
The Centers for Disease Control and Prevention recommend obtaining blood cultures from each lumen of the catheter in addition to peripheral cultures to help determine if the catheter is the source of infection 1
The European Society of Clinical Microbiology and Infectious Diseases recommends performing rapid identification tests when available to detect the presence of Staphylococcus aureus and determine methicillin susceptibility to guide appropriate therapy 4, 5

The American College of Cardiology recommends initiating empiric vancomycin therapy (15-20 mg/kg IV every 8-12 hours, adjusted for renal function) while awaiting final identification and susceptibility testing 1, 2
The Infectious Diseases Society of America suggests tailoring antibiotic treatment early after rapid bacterial identification by mass spectrometry or other rapid diagnostic methods 4, 5
The National Institutes of Health recommend monitoring vancomycin trough levels in patients with impaired renal function to avoid toxicity 1

The American Heart Association recommends removing all intravascular catheters if present 2
The Infectious Diseases Society of America suggests continuing antibiotics for 2 weeks for uncomplicated bacteremia and 4-6 weeks for complicated cases (endocarditis, metastatic infection) 2
The European Society of Clinical Microbiology and Infectious Diseases recommends switching from vancomycin to an anti-staphylococcal beta-lactam (oxacillin, nafcillin) if the isolate is methicillin-susceptible (MSSA) 1, 2
The American College of Cardiology recommends performing echocardiography to rule out endocarditis 2

The Infectious Diseases Society of America recommends treating with antibiotics for 5-7 days if the catheter is removed 6
The National Institutes of Health suggest treating for 10-14 days with systemic antibiotics plus antibiotic lock therapy if the catheter is retained 6
The European Society of Clinical Microbiology and Infectious Diseases recommends considering observation without antibiotics if the catheter is removed, the patient has no intravascular or orthopedic hardware, and follow-up blood cultures are negative 6

The American College of Physicians recommends de-escalating from vancomycin to appropriate β-lactam therapy if the isolate is susceptible 3
The Infectious Diseases Society of America suggests using penicillin G or ceftriaxone for penicillin-susceptible streptococci 1
The European Society of Clinical Microbiology and Infectious Diseases recommends continuing vancomycin for Enterococcus faecium pending susceptibility testing 3

The Centers for Disease Control and Prevention recommend obtaining follow-up blood cultures at 48-72 hours to document clearance of bacteremia 2
The National Institutes of Health suggest reassessing therapy when culture and susceptibility results become available, typically within 48-72 hours 1, 3
The Infectious Diseases Society of America recommends de-escalating from vancomycin to appropriate targeted therapy based on susceptibility results 1
The American College of Physicians suggests considering infectious disease consultation for complicated infections or if endocarditis is suspected 3