Infective endocarditis is an infection of the heart valves and the lining of the heart chambers caused mostly by bacteria, and rarely by fungi. If you are experiencing persistent fever, unexplained fatigue, or heart-related symptoms, you can get personalised advice from licensed doctors through Hope Plus. This premium service helps you receive timely care and prevent complications.
Key Takeaways
- Infective endocarditis affects the heart valves and can be acute, sub-acute, or post-operative.
- Early recognition is critical, particularly in patients with pre-existing heart conditions.
- Treatment involves targeted antibiotics, sometimes combined with supportive care for heart failure or embolic complications.
- Preventive measures, such as antibiotic prophylaxis before certain procedures, reduce the risk of infection.
Causes
- Sub-acute endocarditis: Low-virulence organisms like Streptococcus viridans
- Acute endocarditis: Pyogenic organisms such as Staphylococcus aureus
- Post-operative endocarditis: After cardiac surgery or prosthetic valve placement, commonly caused by Staphylococcus aureus
Clinical Features
- Fatigue and weight loss
- Low-grade fever and chills, or acute severe septicaemia
- Embolic phenomena affecting organs such as the brain
- Heart failure and changing heart murmurs
- Splenomegaly and hepatomegaly
- Anaemia, splinter haemorrhages in nails and retina, finger clubbing
- Diagnostic triad: Persistent fever, emboli, and changing heart murmur
Risk Factors
- Rheumatic heart disease or congenital heart defects
- Prosthetic heart valves
- Invasive procedures (dental, diagnostic, surgical, cardiac catheterisation)
- Immunosuppression or IV drug use
- Any unexplained fever in a patient with a heart valve problem should be regarded as possible endocarditis
Differential Diagnosis
- Heart failure with murmurs
- Febrile conditions associated with anaemia
Investigations
- Blood cultures: At least three separate sets, one hour apart, to identify the pathogen and antibiotic sensitivity
- Complete blood count, ESR, urinalysis
- Echocardiography to assess valve involvement
- ECG for cardiac function
Treatment
- Bed rest and management of complications such as heart failure
- Empirical antibiotic therapy:
- Benzylpenicillin 5 MU IV every 6 hours for 4 weeks is prescribed and administered by the healthcare provider.
- For children: 50,000 IU/kg every 6 hours for 4 weeks
- Gentamicin 1 mg/kg IV every 8 hours for 2 weeks is administered if indicated
- Benzylpenicillin 5 MU IV every 6 hours for 4 weeks is prescribed and administered by the healthcare provider.
- If Staphylococcus is suspected (acute onset):
- Cloxacillin IV 3 g every 6 hours is administered
- Children: 50 mg/kg every 6 hours for 4 weeks
- If MRSA is identified:
- Vancomycin 500 mg IV every 6 hours is administered
- Children: 10 mg/kg IV every 6 hours for 6 weeks
- Once the pathogen is confirmed, antibiotics are adjusted according to sensitivity results
Prevention
- Antibiotic prophylaxis before dental procedures, tonsillectomy, or other interventions in at-risk patients (those with valvular defects, congenital heart disease, or prosthetic valves)
- Amoxicillin 2 g orally (50 mg/kg for children) as a single dose, one hour before the procedure
