From the Guidelines
The treatment for infective endocarditis primarily involves prolonged antibiotic therapy, typically administered intravenously for 4-6 weeks, with initial empiric therapy often including a combination of vancomycin and ceftriaxone while awaiting blood culture results. The choice of antibiotics depends on the suspected or confirmed causative organism, with targeted therapy initiated once the organism is identified. For example, streptococcal endocarditis may be treated with penicillin G or ceftriaxone, while staphylococcal endocarditis may require nafcillin, oxacillin, or vancomycin, depending on the strain's susceptibility 1.
Key Considerations
- The duration of antibiotic therapy varies depending on the causative organism and the presence of complications, with native valve endocarditis due to highly susceptible streptococci typically requiring 4 weeks of treatment, and prosthetic valve endocarditis requiring at least 6 weeks of treatment 1.
- Surgical intervention is necessary in about 50% of cases, particularly for heart failure due to valve dysfunction, uncontrolled infection despite antibiotics, prevention of embolic events with large vegetations (>10mm), or prosthetic valve endocarditis 1.
- The timing of surgery is crucial, with emergency surgery needed for severe heart failure or septic shock.
- Treatment success depends on early diagnosis, appropriate antibiotic selection based on culture results, and timely surgical intervention when indicated.
Antibiotic Regimens
- For native valve endocarditis caused by methicillin-susceptible staphylococci, (flu)cloxacillin or oxacillin may be used, while vancomycin is recommended for methicillin-resistant strains 1.
- For prosthetic valve endocarditis, the combination of (flu)cloxacillin or oxacillin, rifampin, and gentamicin may be used for methicillin-susceptible staphylococci, while vancomycin, rifampin, and gentamicin may be used for methicillin-resistant strains 1.
- The addition of gentamicin to vancomycin is not recommended for bacteremia or native valve infective endocarditis, and the addition of rifampin to vancomycin is also not recommended for these cases 1.
Monitoring and Follow-up
- Regular monitoring of blood cultures, renal function, and serum antibiotic levels is essential to ensure effective treatment and minimize toxicity.
- Echocardiography, including transesophageal echocardiography, is recommended for all adult patients with bacteremia to assess for valve involvement and guide treatment decisions 1.
From the FDA Drug Label
Vancomycin Hydrochloride for Injection, USP is effective in the treatment of staphylococcal endocarditis Its effectiveness has been documented in other infections due to staphylococci, including septicemia, bone infections, lower respiratory tract infections, skin and skin structure infections. Vancomycin Hydrochloride for Injection, USP has been reported to be effective alone or in combination with an aminoglycoside for endocarditis caused by S. viridans or S. bovis. For endocarditis caused by enterococci (e.g., E. faecalis), vancomycin has been reported to be effective only in combination with an aminoglycoside.
The treatment for infective endocarditis may include vancomycin alone or in combination with an aminoglycoside, depending on the causative organism.
- For staphylococcal endocarditis, vancomycin is effective.
- For endocarditis caused by S. viridans or S. bovis, vancomycin alone or in combination with an aminoglycoside is effective.
- For endocarditis caused by enterococci, vancomycin in combination with an aminoglycoside is effective 2. Gentamicin may also be used in combination with other antibiotics for the treatment of endocarditis caused by certain organisms, such as group D streptococci or staphylococci 3. Ampicillin may be used to treat endocarditis caused by susceptible Gram-positive organisms, including Streptococcus spp. and enterococci, and the addition of an aminoglycoside may enhance its effectiveness 4.
From the Research
Treatment Overview
- The treatment for infective endocarditis typically involves antibacterial therapy, with the specific regimen depending on the causative organism and its resistance pattern 5, 6, 7.
- For native valve endocarditis, the optimal duration of antibacterial treatment is 4 weeks, while for prosthetic-valve endocarditis, it is 6 weeks 5.
- The use of aminoglycosides has been dramatically reduced over the last 20 years and should be administered once daily, and no longer than 2 weeks 5.
Specific Treatment Regimens
- For staphylococcal endocarditis, anti-staphylococcal penicillins, such as cefazolin, are recommended for methicillin-susceptible isolates, while vancomycin is recommended for methicillin-resistant isolates 5, 6.
- For streptococcal endocarditis, penicillin G alone or in combination with streptomycin is effective 7.
- For enterococcal endocarditis, a combination of penicillin G and an aminoglycoside, such as gentamicin, is recommended 7.
Multidisciplinary Care
- Multidisciplinary care is imperative to the management of infective endocarditis, often requiring the expertise of cardiologists, cardiothoracic surgeons, infectious diseases specialists, radiologists, and neurologists 8, 9.
- A team-based approach can help to initiate the appropriate investigation and treatment, and to manage potential complications 9.