The Center For Disease Dynamics, Economics & Policy

Infective Endocarditis

Native valve endocarditis

Clinical definition:

Symptoms may be variable and non-specific. Common etiologies include S. aureusA and streptococcal and enterococcal species.

 

Preferred antibiotic choice(s)
Drug Formulation Dosage Duration
Combination therapy with:

Benzylpenicillin (penicillin G, IV)

PLUS

Gentamicin (IV)

Powder for injection: 600 mg; 3 g (sodium or potassium salt) in vial 5 MU 6 hourly 28 days
Gentamicin- Injection: 10 mg; 40 mg (as sulfate)/mL in 2- mL vial 3 mg/kg daily 14 days
Alternative antibiotic choice(s)
Combination therapy with:

Ampicillin (IV)

PLUS

Gentamicin (IV)

Ampicillin- Powder for injection: 500 mg; 1 g (as sodium salt) in vial 2 g 4 hourly 28 days
Gentamicin- Injection: 10 mg; 40 mg (as sulfate)/mL in 2mL vial  

3 mg/kg daily

14 days
In case of confirmed drug allergy or medical contraindication
Vancomycin (IV) Powder for injection: 250 mg (as hydrochloride) in vial 20 mg/kg 12 hourly 6 weeks

Prosthetic valve or pacemaker infection

 

Clinical definition:

Infection associated with insertion or presence of prosthetic valve, pacemaker, or implanted defibrillator. Common etiologies include S. aureus, S. epidermidis, and other staphylococcal species.

 

Preferred antibiotic choice(s)
Drug Formulation Dosage Duration
Combination therapy with:

Vancomycin (IV)

PLUS

Gentamicin (IV)

PLUS

Rifampicin (PO)

 

Vancomycin- Powder for injection: 250 mg (as hydrochloride) in vial Loading dose: 25 – 30 mg/kg followed by maintenance dose: 10 – 15 mg/kg 6 weeks
Gentamicin- Injection: 10 mg; 40 mg (as sulfate)/ mL in 2- mL vial 3 mg/kg daily 2 weeks
Rifampicin- Oral liquid: 20 mg/mL; Solid oral dosage form: 150 mg; 300 mg 7.5 mg/kg 12 hourly 6 weeks

 

 

A. If there are risk factors for S. aureus (e.g. patient is an IV drug user, if vegetation is very large, or patient has rapidly accelerating symptoms), add cloxacillin.

 

Principles of Stewardship:

  • For suspected infective endocarditis cases, 3 blood cultures should be obtained in rapid succession from 3 anatomic sites within 6 hours before administration of antibiotic therapy.
  • Approximately 10% of endocarditis cases are culture negative. The most common reason for which is receipt of antibiotics prior to the blood cultures. True, culture-negative endocarditis suggests infection by a fastidious organism, and includes Bartonella sp., Coxiella burnetti (Q Fever), and Brucella sp, each of which associate with specific risk factors. Discuss investigation and treatment options with your local pathology laboratory.