Rheumatic fever & infective endocarditis

Question 1

Rheumatic fever

Answer 1

Rheumatic fever develops following an immunological reaction to recent (2-6 weeks ago) Streptococcus pyogenes infection.

Question 2

What histological features are seen in rheumatic fever?

Answer 2

Aschoff bodies describes the granulomatous nodules found in rheumatic heart fever

Question 3

Management of rheumatic fever

Answer 3

1. antibiotics: oral penicillin V
2. anti-inflammatories: NSAIDs are first line
3. treatment of any complications that develop e.g. heart failure

Question 4

Endocarditis

Answer 4

Endocarditis (or infective endocarditis) is a rare condition where the inner lining of the heart chambers and valves (the endocardium) becomes infected.

Question 5

Risk factors for infective endocarditis

Answer 5

1. previously normal valves (50%, typically acute presentation) - the mitral valve is most commonly affected
2. rheumatic valve disease (30%)
3. prosthetic valves
4. congenital heart defects
5. intravenous drug users
6. others: recent piercings

Question 6

What is the most commonly affected valve in endocarditis?

Answer 6

The mitral valve is most commonly affected

Question 7

What is the most common cause of infective endocarditis?

Answer 7

Staphylococcus aureus is now the most common cause of infective endocarditis.

Staphylococcus aureus is also particularly common in acute presentation and IVDUs

Question 8

What is the most common cause of infective endocarditis in patients following prosthetic valve surgery?

Answer 8

Coagulase-negative Staphylococci such as Staphylococcus epidermidis

Question 9

What is the most common cause of infective endocarditis in patients following following a dental procedure or poor dental hygeine?

Answer 9

Streptococcus viridans

Question 10

What is the most common cause of infective endocarditis in intravenous drug users?

Answer 10

Staphylococcus aureus is also particularly common in acute presentation and IVDUs

Question 11

What are the indications for surgery in infective endocarditis?

Answer 11

o severe valvular incompetence
o aortic abscess (often indicated by a lengthening PR interval)
o infections resistant to antibiotics/fungal infections
o cardiac failure refractory to standard medical treatment
o recurrent emboli after antibiotic therapy

Question 12

What is the initial BLIND management of infective endocarditis in native and prosthetic valves?

Answer 12

Native valve - amoxicillin

If penicillin allergic, MRSA or severe sepsis
- vancomycin + low-dose gentamicin

If prosthetic valve - vancomycin + rifampicin + low-dose gentamicin

Question 13

What is the management of Native valve endocarditis caused by staphylococci?

Answer 13

Flucloxacillin

If penicillin allergic or MRSA - vancomycin + rifampicin

Question 14

What is the management of Prosthetic valve endocarditis caused by staphylococci

Answer 14

Flucloxacillin + rifampicin + low-dose gentamicin

If penicillin allergic or MRSA - vancomycin + rifampicin + low-dose gentamicin

Question 15

What is the management of Endocarditis caused by fully-sensitive streptococci (e.g. viridans)?

Answer 15

Benzylpenicillin

If penicillin allergic - vancomycin + low-dose gentamicin

Question 16

What is the management of Endocarditis caused by less sensitive streptococci?

Answer 16

Benzylpenicillin + low-dose gentamicin

If penicillin allergic - vancomycin + low-dose gentamicin