Endocarditis

Question 1

Which organis, is the most common cause of endocarditis? What happens after infection? How is it treated?

Answer 1

Streptococcus viridians infection on the surface of the cardiac valves. It infects previously damaged valves (chronic rheumatic heart disease and MVP). Results in small vegetations that don’t destroy the valve.Prophylactic antibiotics decrease risk of endocarditis

Question 2

How does Streptococcus viridians end up on the valves?

Answer 2

1. Damaged endocardial surface develops thrombotic vegetations 2. Transient bacteremia leads to trapping of bacteria in the vegetation.

Question 3

What is the most common cause of endocarditis in IV drug abusers? Which valves are affected? What does it cause?

Answer 3

Staphylococcus aureus is the most common cause. Infects normal valves, most commonly the tricuspid. Results in learge vegetations that destroy the valve (acute endocarditis).

Question 4

Which organism is associated with endocarditis of prosthetic valves?

Answer 4

Staphylococcus epidermidis

Question 5

Which organism is associated with endocarditis in patients with underlying colorectal carcinoma?

Answer 5

Streptococcus bovis

Question 6

Which organism is associated with endocarditis in patients with negative blood cultures?

Answer 6

HACEK organisms (Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella)

Question 7

What are the clinical features of endocarditis?

Answer 7

1. Fever due to bacteremia 2. Murmur due to vegetation on heart valve 3. Janeway lesions, Osler nodes, splinter hemorrhages in nail bed and Roth spots due to embolization of septic vegetation 4. Anemia of chronic disease due to chronic inflammation

Question 8

What are laboratory findings in endocarditis? What is useful for detecting valvular lesions?

Answer 8

1. Positive blood cultures 2. Anemia of chronic disease (low Hb, low MCV, high ferritin, low TIBC, low serum Iron and low % saturation)
   - Transesophageal echocardiogram

Question 9

What causes non bacterial thrombotic endocarditis? Which valves are involved?

Answer 9

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.

Question 10

What causes non bacterial thrombotic endocarditis? Which valves are involved and what does it result in?

Answer 10

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.

Question 11

What causes Libman-Sacks endocarditis? Which valves are involved and what does it result in?

Answer 11

Sterile vegetations that arise in association with SLE. Vegetations are present on the surface and undersurface of the mitral valve and result in mitral regurgitation.