Endocarditis Flashcards
What is endocarditis?
Inflammation of endocardium that lines the surface of cardiac valves; usually due to bacterial infection
What is the most common cause of endocarditis?
Streptococcus viridans is the most common overall cause. It is a low-virulence organism that infects previously damaged valves (e.g., chronic rheumatic heart disease and mitral valve prolapse). Results in small vegetations that do not destroy the valve (subacute endocarditis)
What happens to damaged endocardial surface in endocarditis?
Damaged endocardial surface develops thrombotic vegetations (platelets and fibrin).
How do you decrease the risk of endocarditis?
Prophylactic antibiotics decrease risk of endocarditis.
What is the most common cause of endocarditis in IV drug abusers?
Staphylococcus aureus is the most common cause in IV drug abusers
What valve does Staphylococcus aureus most commonly affect?
High-virulence organism that infects normal valves, most commonly the tricuspid
What bacteria is associated with endocarditis of prosthetic valves?
Staphylococcus epidermidis is associated with endocarditis of prosthetic valves.
What bacteria is associated with endocarditis in patients with underlying colorectal carcinoma?
Streptococcus bovis is associated with endocarditis in patients with underlying colorectal carcinoma.
What organisms are associated with negative blood cultures in endocarditis?
HACEK organisms are associated with endocarditis with negative blood cultures.
Which are the HACEK organisms?
HACEK organisms (Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella)
What are the clinical features of bacterial endocarditis?
- Fever—due to bacteremia
- Murmur—due to vegetations on heart valve
- Janeway lesions (erythematous nontender lesions on palms and soles). 4.Osler nodes (tender lesions on fingers or toes) 5.Splinter hemorrhages in nail bed -due to embolization of septic vegetations
- Anemia of chronic disease—due to chronic inflammation
What are the laboratory findings in endocarditis?
- Positive blood cultures
- Anemia of chronic disease
- Transesophageal echocardiogram is useful for detecting lesions on valves
What is nonbacterial thrombotic endocarditis?
Nonbacterial thrombotic endocarditis is due to sterile vegetations that arise in association with a hypercoagulable state or underlying adenocarcinoma. Vegetations arise on the mitral valve along lines of closure and result in mitral regurgitation,
What is Libman-Sacks endocarditis?
