From the Guidelines
For treating Staphylococcus bacteremia, the most effective antibiotics are cefazolin or an anti-staphylococcal penicillin (ASP) for methicillin-sensitive S. aureus (MSSA) and vancomycin or daptomycin for methicillin-resistant S. aureus (MRSA), as recommended by the most recent guidelines 1.
Key Considerations
- The choice of antibiotic depends on whether the infection involves MSSA or MRSA strains.
- For MSSA bacteremia, cefazolin is a preferred treatment option, offering less frequent dosing compared to traditional anti-staphylococcal penicillins.
- For MRSA bacteremia, vancomycin and daptomycin are standard treatments, with vancomycin requiring dose adjustments based on levels and daptomycin serving as an alternative, especially in cases of vancomycin resistance or intolerance.
Treatment Duration
- Treatment typically requires 4–6 weeks for bacteremia with high-risk features, as outlined in recent clinical practice guidelines 1.
- The duration of therapy should be guided by the clinical response, the presence of complicating factors such as endocarditis or osteomyelitis, and the results of follow-up blood cultures.
Additional Recommendations
- Early source control, including the removal of infected catheters or drainage of abscesses, is crucial for the effective management of Staphylococcus bacteremia 1.
- Infectious disease consultation is recommended for complicated cases, especially those involving prosthetic devices, persistent bacteremia, or when the patient's condition does not improve with standard therapy.
- Local antibiograms should guide the selection of antibiotics until susceptibility results are available, considering the geographic variation in resistance patterns 1.
From the FDA Drug Label
In the S. aureus bacteremia/endocarditis trial involving adult patients, daptomycin for injection was discontinued in 20/120 (16.7%) patients due to an adverse reaction, while comparator was discontinued in 21/116 (18.1%) patients. The rates of the most common adverse reactions, organized by System Organ Class (SOC), observed in adult patients with S aureus bacteremia/endocarditis (receiving 6 mg/kg daptomycin for injection) are displayed in Table 7. Comparator: vancomycin (1 g IV q12h) or an anti-staphylococcal semi-synthetic penicillin (i.e., nafcillin, oxacillin, cloxacillin, or flucloxacillin; 2 g IV q4h), each with initial low-dose gentamicin
Effective antibiotics for bacteremia caused by Staphylococcus include:
- Daptomycin (IV)
- Vancomycin (1 g IV q12h)
- Anti-staphylococcal semi-synthetic penicillin (i.e., nafcillin, oxacillin, cloxacillin, or flucloxacillin; 2 g IV q4h) Key points:
- Daptomycin for injection was effective in treating S. aureus bacteremia/endocarditis in adult patients.
- The comparator drugs, vancomycin and anti-staphylococcal semi-synthetic penicillin, were also effective in treating S. aureus bacteremia/endocarditis. 2
From the Research
Effective Antibiotics for Bacteremia Caused by Staphylococcus
- The choice of antibiotic for treating bacteremia caused by Staphylococcus depends on the methicillin susceptibility of the pathogen 3, 4.
- For methicillin-susceptible Staphylococcus aureus (MSSA), cefazolin or antistaphylococcal penicillins are recommended 3.
- For methicillin-resistant Staphylococcus aureus (MRSA), vancomycin, daptomycin, or ceftobiprole are recommended 3, 5.
- Initial treatment for Staphylococcus aureus bacteremia typically includes antibiotics active against MRSA, such as vancomycin or daptomycin, until antibiotic susceptibility results are available 3.
- Combination therapy, such as daptomycin plus oxacillin, may be effective for persistent MSSA bacteremia 6.
Treatment Considerations
- Source control is a critical component of treating Staphylococcus aureus bacteremia and may include removal of infected intravascular or implanted devices, drainage of abscesses, and surgical debridement 3.
- Identifying sites of metastatic infection and pursuing source control for identified foci of infection are important aspects of clinical management 3.
- Optimized dosing of antibiotics is increasingly being recognized as a cornerstone of management for severe infections, including Staphylococcus aureus bacteremia 7.