Infective Endocarditis

Question 1

What are the major pathogens implicated in IE?

Answer 1

• Viridians group streptococci (35%)
• Staph auerus
• Enterococci
• Coagulase negative staphylococcus

Question 2

what are the major pathogens seen in IVDU related IE?

Answer 2

• S. Aureus
• Streptococci
• Gram negative bacilli

Question 3

what are the RF’s for IE?

Answer 3

Prosthetic valves 
congenital heart defect 
post heart transplant 
IVDU 
mitral regurg 
hypertrophic cardiomyopathy

Question 4

what are the clinical classifications of IE and their features?

Answer 4

Acute = days to weeks and characterised by spiking fevers, tachycardia, fatigue.

Subacute = weeks to months and usually involves vague constitutional symptoms

Question 5

what is the location classification of IE

Answer 5

Native valve endocarditis
prosthetic valve endocarditis
device related IE
Right sided IE - typically seen in IVDU

Question 6

what are the infective signs of IE?

Answer 6

fevers, night sweats, malaise, weight loss, rigors, splenomegaly, anaemia, clubbing

Question 7

what are the cardiac signs of IE?

Answer 7

new murmur or change to existing one
valve regurg
Aortic root abscess may prolong PR and AV block

Question 8

whats are the immune complex deposition signs of IE?

Answer 8

Vasculitis
Microscopic haematuria as glomerulonephritis may occur
Roth spots (boat shaped retinal haemorrhage with pale centre)
Splingter haemorrhages
Oslers nodes

Question 9

what are the embolic signs of IE?

Answer 9

abscesses in organs affected by emboli

Janeway lesions are painless palmar or plantar macules that occur with embolus of the skin

Question 10

What are the invesigations for IE?

Answer 10

• Echo
• Blood cultures. 3 sets at different times from different sites
• FBC. normochromic normocytic anaemia and leucocytosis
• U&E’s, LFTs, magnesium. check for liver/kidney compications
• ECG. Prolonged PR and AV block in aortic root abscess
• urinalysis. protein/haematuria in glomerulonephritis

Question 11

IE is diagnosed when a patient has 2 major Duke’s criteria, 1 major and 3 minor or 5 minor criteria. What is Dukes criteria?

Answer 11

Major

• Positive blood cultures for typical pathogen
• evidence of endocardial involvement i.e positive echo or new valvular regurg

Minor

• Predisposition (cardiac lesion, IVDU)
• Fever >38
• vascular/immunlogical sign
• positive blood culture that does not meet major criteria
• positive echo that does not meet major criteria

Question 12

what is the blind ABx therapy for IE?

Answer 12

Native valve = Amox and Gent IV

Prosthetic valve = Vanc + Gent + rifampicin IV

Question 13

A patient with IE has grown a staphylococcus on culture. What is the ABx treatment for both native and prosthetic valve?

Answer 13

Native = Flucloxacillin IVI for >4 weeks

Prosthetic = Flucloxacillin + Gent + rifampicin for 6 weeks

Question 14

A patient with IE has grown a streptococci on culture. What ABx therapy should be used? How does pathogen sensitivites affect choice?

Answer 14

if penicillin sensitive then Benzylpencillin for 4-6 weeks IV

If pencillin resistant then Vanc and Gent

Question 15

A patient with IE has grown an enterococci on culture. What ABx therapy should be used?

Answer 15

Amox and Gent

Question 16

What are HAECK organism and how can they be targeted?

Answer 16

Haemophilus actinobacillus, cardiobacterium, kingella

Amox for 4 weeks and Gent for 2

Question 17

what are the complications of IE?

Answer 17

Cogestive HF due to aortic valve insufficiency
Systemic emboli - stroke, renal infarct etc
Glomerulonephritis and other kidney damage
abscesses