Infective Endocarditis (3.4)

Question 1

Name some peripheral signs often present in infective endocarditis (5)

Answer 1

Petechiae
Subungual (splinter) haemorrhages
Osler nodes
Janeway lesions
Roth spots (rare)

Question 2

What is the criteria framework used for diagnosis of infective endocarditis?

Answer 2

Modified Duke Criteria
(2 major, 1 major 3 minor, 5 minor)

Question 3

What are the major criteria for IE?

Answer 3

Positive blood culture
Evidence of endocardial involvement

Question 4

What counts as a positive blood culture for IE in the modified duke criteria?

Answer 4

1. Blood culture positive for IE:

A. Typical microorganisms consistent with IE from 2 separate blood cultures:

Viridans streptococci, Streptococcus bovis, HACEK group, Staphylococcus aureus;
or
Community-acquired enterococci, in the absence of a primary focus;

B. Microorganisms consistent with IE from persistently positive blood cultures, defined as follows:

At least 2 positive cultures of blood samples drawn >12h apart; or
All of 3 or a majority of >4 separate cultures of blood (with first and last sample drawn at least 1h apart);

C. Single positive blood culture for Coxiella burnetii or phase I IgG antibody titre >1:800

Question 5

What counts as evidence of endocardial involvement in IE in the modified duke criteria?

Answer 5

A. Echocardiogram positive for IE

Vegetation
Abscess, pseudoaneurysm, intracardiac fistula
Valvular perforation or aneurysm
New partial dehiscence of prosthetic valve
B. Abnormal activity around the site of prosthetic valve implantation detected by 18F-FDG PET/CT (only if the prosthesis was implanted for >3 months) or radiolabelled leukocytes SPECT/CT

C. Definite paravalvular lesions by cardiac CT

Question 6

What is the main focus of endocarditis management?

Answer 6

-Early identification
-Blood cultures from 3 separate sites before antibiotic administration (unless the patient is septic)
-Transthoracic echo (TTE) is first line imaging modality
-Transoesophageal echo (TOE) is used where there is high suspicion of IE but TTE is not confirmatory
-Referral to endocarditis MDT
-Assessment of embolic complications
-Timing of surgery (in case of need for valve repair or replacement)