What is the treatment for gram-positive cocci bacteremia?

From the Guidelines

The treatment for gram-positive cocci bacteremia should start with vancomycin as the empiric therapy, especially in healthcare settings with a high prevalence of methicillin-resistant staphylococci, as recommended by the Infectious Diseases Society of America 1. When considering the treatment for gram-positive cocci bacteremia, it's crucial to differentiate between methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA), as well as other gram-positive cocci such as streptococci and enterococci.

• For MRSA, vancomycin is the preferred initial treatment, with a dosage of 15-20 mg/kg IV every 8-12 hours, considering the institution's vancomycin MIC values 1.
• For MSSA, nafcillin or oxacillin (2 g IV every 4 hours) is the preferred treatment.
• Daptomycin (6-8 mg/kg IV daily) is an alternative for patients with vancomycin intolerance or in areas with high vancomycin MICs, as suggested by the guidelines 1.
• The duration of antibiotic therapy typically ranges from 2 weeks for uncomplicated bacteremia to 4-6 weeks for complicated cases, such as those involving endocarditis or osteomyelitis, with the specific duration guided by factors such as the causative organism, the presence of complications, and the patient's clinical response 1. Key considerations in the management of gram-positive cocci bacteremia include:
• The need for source control, such as removal of infected catheters or drainage of abscesses.
• Monitoring with repeat blood cultures to confirm clearance of bacteremia.
• Clinical assessment and evaluation of inflammatory markers to gauge treatment response.
• Adjustment of empiric therapy to targeted therapy based on culture and sensitivity results, which is crucial for optimizing outcomes and minimizing antibiotic resistance 1.

From the FDA Drug Label

The cure rates by pathogen for microbiologically evaluable patients are presented in Table 19. Table 19 Cure Rates at the Test-of-Cure Visit for Microbiologically Evaluable Adult Patients with Diabetic Foot Infections Pathogen Cured ZYVOX n/N (%) Comparator n/N (%) Staphylococcus aureus 49/63 (78) 20/29 (69) Methicillin-resistant S aureus 12/17 (71) 2/3 (67) Streptococcus agalactiae 25/29 (86) 9/16 (56)

Table 20 Intent to Treat, and Clinically Evaluable Pediatric Patients by Baseline Diagnosis Population ITT MITT* Clinically Evaluable ZYVOX n/N (%) Vancomycin n/N (%) ZYVOX n/N (%) Vancomycin n/N (%) ZYVOX n/N (%) Vancomycin n/N (%)

• MITT = ITT patients with an isolated Gram-positive pathogen at baseline Any diagnosis 150/186 (81) 69/83 (83) 86/108 (80) 44/49 (90) 106/117 (91) 49/54 (91) Bacteremia of unidentified source 22/29 (76) 11/16 (69) 8/12 (67) 7/8 (88) 14/17 (82) 7/9 (78)

Table 21 Cure Rates at the Test-of-Cure Visit for Microbiologically Evaluable Pediatric Patients with Infections due to Gram-positive Pathogens Pathogen Microbiologically Evaluable ZYVOX n/N (%) Vancomycin n/N (%)

• Includes data from 7 patients enrolled in the open-label extension of this study Vancomycin-resistant Enterococcus faecium 6/8 (75)* 0/0 (-) Staphylococcus aureus 36/38 (95) 23/24 (96) Methicillin-resistant S. aureus 16/17 (94) 9/9 (100) Streptococcus pyogenes 2/2 (100) 1/2 (50)

The treatment for gram-positive cocci bacteremia includes linezolid and vancomycin.

• Linezolid has cure rates of 71% in adult patients with Gram-positive pathogens isolated from the site of infection or from blood, and 80% in pediatric patients with an isolated Gram-positive pathogen at baseline.
• Vancomycin has cure rates of 63% in adult patients with Gram-positive pathogens isolated from the site of infection or from blood, and 90% in pediatric patients with an isolated Gram-positive pathogen at baseline. Key pathogens and their corresponding cure rates with linezolid and vancomycin are:
• Staphylococcus aureus: 78% (linezolid), 69% (comparator)
• Methicillin-resistant S aureus: 71% (linezolid), 67% (comparator)
• Streptococcus agalactiae: 86% (linezolid), 56% (comparator)
• Vancomycin-resistant Enterococcus faecium: 75% (linezolid) 2

From the Research

Treatment Options for Gram-Positive Cocci Bacteremia

• Vancomycin remains a first-line treatment drug for methicillin-resistant Staphylococcus aureus (MRSA) bacteremia, as per treatment guidelines 3.
• Daptomycin combined with linezolid is an effective remedy for bacteremia caused by MRSA with pulmonary complications 3.
• Vancomycin is also used to treat other serious gram-positive cocci infections, including streptococcal endocarditis and corynebacterial endocarditis 4.
• Linezolid has been shown to be effective against MRSA bacteremia, with comparable effectiveness and safety to vancomycin, teicoplanin, or daptomycin 5.
• The empirical combination of vancomycin and a β-lactam agent may improve infection-related clinical outcomes for Staphylococcus aureus bacteremia 6.
• Other antibiotics, such as quinupristin/dalfopristin and linezolid, show promise against gram-positive bacteria that are resistant to vancomycin 7.

Antibiotic Resistance and Treatment Considerations

• The development of resistance to vancomycin and other antibiotics is a concern, and judicious use of these drugs is necessary to promote their effectiveness 4, 7.
• The choice of antibiotic should be based on the specific type of gram-positive cocci and the severity of the infection, as well as the patient's renal function and other factors 4, 6.
• Combination therapy, such as the use of vancomycin and a β-lactam agent, may be considered in certain cases to improve clinical outcomes 6.