Infective Endocarditis

Question 1

What are risk factors for it?

Answer 1

• rheumatic valve disease
• prosthetic valves
• IVDUs
• congenital heart defects

Question 2

What valve is most commonly effected in previously normal valves?

Answer 2

mitral valve

Question 3

What bacteria is the most common cause for infective endocarditis?

Answer 3

staph aureus

Question 4

What bacterial cause would you expect in the following circumstances?

1. IVDU
2. poor dental hygiene / following dental procedure
3. indwelling line
4. following prosthetic valve surgery
   (within 2 months - after 2 months returns to staph aureus)
5. colorectal cancer
6. culture negative

Answer 4

1. staph aureus
2. strep. viridans
3. staph epidermidis
4. staph epidermidis
5. strep. bovis
6. • coxiella burnetii
   • bartonella
   • brucella
   • haemophilus

mnemonic: 3 Bs

Question 5

What are the indicators of poor prognosis?

Answer 5

• staph aureus
• culture negative staph
• prosthetic heart valve

Question 6

State the treatment in following scenarios prior to knowing the causative organism

1. native valve
2. pen. allergic / severe sepsis
3. prosthetic valve

Answer 6

1. amoxicillin +/- gentamicin
2. vancomycin + gentamicin
3. vancomycin, gentamicin, rifampicin

Question 7

State the treatment for the following causative organisms:

1. staph
   a) native valve
   b) prosthetic valve
2. strep
   a) fully sensitive
   b) less sensitive

Answer 7

1. a) flucloxacillin
   if penicillin allergic: vancomycin + rifampicin

b) flucloxacillin, gentamicin, rifampicin
if penicillin allergic: vancomycin, gentamicin, rifampicin

2. a) benzylpenicillin
   if penicillin allergic: vancomycin + gentamicin

b) benzylpenicillin + gentamicin
if penicillin allergic: vancomycin + gentamicin

Question 8

When is prophylaxis for infective endocarditis indicated?

Answer 8

• person at risk of endocarditis is having a procedure done for another infection (likely already on ABx - want one covering likely bacterial endocarditis organisms)

Additionally, if someone who is at risk of endocarditis presents with an infection they should be investigated and treated promptly

NOTE: not for just anyone getting dental procedure or endoscopy