Infective endocarditis

Question 1

What 4 (general) investigations are done if infective endocarditis is suspected?

Answer 1

Blood cultures
Echocardiography
Non-specific tests
Investigation of other possible points of infection
Serology

Question 2

What laboratory tests are done in infective endocarditis?

Answer 2

Cultures of any material removed surgically
Blood cultures (examined for signs of growth)
Prolonged cultures (10 days)

Any positive cultures sub cultured onto other agar plated (which depending on gram film)

Question 3

Name 8 of the most common causes of infective endocarditis found in blood cultures

Answer 3

Staphylococcus aureus
Coagulase negative staphylococcus
Strep.pneumoniae
B-haemolytic streptococcus
Enterococci
Coliforms
Psuedomonas spp.
Neisseria meningitidis

Question 4

What is the most common cause of infective endocarditis found in blood cultures and give a common source?

Answer 4

Coagulase negative staphylococcus

Common source = IV line contamination

Question 5

What are the 2 major criteria on the modified Duke criteria?

Answer 5

1) Positive blood culture with typical infective endocarditis microorganism
2) New partial dehiscence of prosthetic valve or new valvular regurgitation

Question 6

Give 5 minor criteria named in the modified Duke criteria:

Answer 6

1) Predisposing factor
2) Fever >38o
3) Embolism evidence
4) Immunological problems
5) Microbiological evidence –> positive blood culture but not with a typical microorganism