From the Guidelines
Staphylococcus bacteremia treatment should prioritize vancomycin as the standard of care for most patients with MRSA bacteremia, with dosing optimized through individualized area under the curve (AUC) monitoring with Bayesian software programs, as recommended by revised consensus guidelines published in 2020 1. The treatment of Staphylococcus bacteremia requires prompt intravenous antibiotics, with the specific regimen depending on methicillin susceptibility.
- For methicillin-resistant Staphylococcus aureus (MRSA), vancomycin is the preferred treatment, with a dose of 15-20mg/kg IV every 8-12 hours (adjusted for renal function and to achieve trough levels of 15-20 μg/mL) 1.
- Daptomycin 6-10mg/kg IV daily is an alternative for MRSA, especially in cases of vancomycin failure, with some experts recommending higher doses of 8-12 mg/kg IV daily due to its concentration-dependent bactericidal activity 1.
- The treatment duration is typically 2 weeks for uncomplicated bacteremia, but extends to 4-6 weeks for complicated cases involving endocarditis, osteomyelitis, or persistent bacteremia 1.
- Blood cultures should be repeated every 24-48 hours until clearance is documented, and source control is essential, requiring removal of infected catheters or drainage of abscesses when present 1.
- Echocardiography is recommended to rule out endocarditis, particularly with community-acquired S. aureus bacteremia, as it can rapidly lead to metastatic infections and has high mortality if inadequately treated 1. The available evidence does not support the routine addition of rifampin or gentamicin for SAB or native valve IE due to S. aureus, and linezolid and trimethoprim-sulfamethoxazole (TMP-SMX) are not recommended as first-line treatment of SAB due to a lack of well-conducted clinical trial data and concerns about tolerability 1.
From the FDA Drug Label
- 2 Staphylococcus aureus Bloodstream Infections (Bacteremia) in Adult Patients, Including Those with Right-Sided Infective Endocarditis, Caused by Methicillin-Susceptible and Methicillin-Resistant Isolates Daptomycin for injection is indicated for the treatment of adult patients with Staphylococcus aureus bloodstream infections (bacteremia), including adult patients with right-sided infective endocarditis, caused by methicillin-susceptable and methicillin-resistant isolates.
1.3 Staphylococcus aureus Bloodstream Infections (Bacteremia) in Pediatric Patients (1 to 17 Years of Age) Daptomycin for injection is indicated for the treatment of pediatric patients (1 to 17 years of age) with Staphylococcus aureus bloodstream infections (bacteremia).
Daptomycin is indicated for the treatment of Staphylococcus aureus bloodstream infections (bacteremia) in both adult and pediatric patients (1 to 17 years of age). The recommended dosage for adults is 4 mg/kg intravenously once every 24 hours. For pediatric patients, the dosage and administration instructions are as follows:
- Pediatric Patients 7 to 17 years of Age: Administer daptomycin for injection intravenously by infusion over a 30-minute period.
- Pediatric Patients 1 to 6 years of Age: Administer daptomycin for injection intravenously by infusion over a 60-minute period 2.
From the Research
Treatment Options for Staph Bacteremia
- Vancomycin and daptomycin are options for the initial treatment of patients with methicillin-resistant Staphylococcus aureus (MRSA) bacteremia 3, 4.
- Daptomycin has shown noninferiority to vancomycin in the treatment of MRSA bacteremia 3.
- For patients with MRSA bacteremia and vancomycin minimum inhibitory concentration (MIC) > 1 µg/mL, daptomycin may be a better option than vancomycin 5.
- Treatment options for persistent MRSA bacteremia or bacteremia due to vancomycin-intermediate or vancomycin-resistant strains include daptomycin, ceftaroline, and combination therapies 4, 6.
Considerations for Treatment
- The choice of treatment should take into account the patient's specific situation, including the source of the infection and the presence of any underlying conditions 7.
- Combination therapies, such as high-dose daptomycin in combination with an antistaphylococcal β-lactam, may be effective for persistent MRSA bacteremia 6.
- The use of anti-MRSA cephalosporins, such as ceftaroline, should be reserved for patients with MRSA infections to minimize the risk of resistance 3.