Infective Endocarditis

Question 1

What symptom and sign should make you think f infective endocarditis immediately?

Answer 1

Fever + new murmur

Question 2

Acute infective endocarditis usually occurs on abnormal valves. TRUE/FALSE?

Answer 2

FALSE
Acute = normal valves
- normally caused by staph aureus infection
- skin breach => IV lines, wounds
- renal failure
- immunosuppression
- diabetes

SUBACUTE = abnormal valves
Risk factors include:
Pre-existing aortic/mitral disease
Tricuspid in IVDU
coarctation of aorta
PDA
VSD
Prosthetic valves

Question 3

Name 3 common organisms which cause IE

Answer 3

Strep viridans
Staph aureus
Strep Bovis (assoc with colon ca)
Enterocccus
Coxiella burnetti

Question 4

Name the rare HACEK organisms which can cause IE

Answer 4

H - haemophilus
A - actinobacillus
C - Cardiobacterium
E - Eikenella
K - Kingella

**note all Gm -ve

Question 5

What other organisms can cause IE, particularly in immunocompromised patients, those with prosthetic valves or IVDUs?

Answer 5

RARE - diptheroids, chlamydia

FUNGAL - candida, aspergillus, histoplasma

Question 6

Non-cardiac signs of IE on examination

Answer 6

Fever/Rigors
night sweats
malaise
weight loss
anaemia
splenomegaly
clubbing

Question 7

Cardiac signs of IE on examination

Answer 7

New murmur/changed murmur

Question 8

What complication of IE can lead to AV Block?

Answer 8

Aortic root abscess

this may >PR interval leading to AV block

Question 9

What signs of IE indicate immune complex deposition?

Answer 9

Vasculitis rash
Microscopic haematuria
ROTH spots - retinal haemorrhages
Splinter haemorrhages
OSLERS Nodes - painful pulp infarcts on fingers/toes

Question 10

Name some signs of embolic phenomena associated with IE

Answer 10

Janeway lesions - painless palmar/plantar macules

Emboli may also cause absecssses to develop in other organs

Question 11

Describe the MAJOR and MINOR DUKE criteria used to diagnose IE

Answer 11

MAJOR:
- 2 positive blood cultures
- Positive ECHO

Minor:
- predisposition (cardiac lesion, IVDU)
- Fever
- immunological signs
- vascular signs
- positive blood culture not meeting major criteria

Question 12

How many MAJOR and MINOR DUKE criteria do you need for a diagnosis of IE

Answer 12

2 Major + 0 Minor
1 Major + 3 Minor
0 Major + 5 Minor

Question 13

What types of IE require more intense Abx regimes?

Answer 13

Prosthetic valves (different abx on guidance)
HACEK organisms - 4 weeks ceftriaxone

Question 14

When is surgery indicated in IE?

Answer 14

• causing heart failure
• valve obstruction
• repeated emboli
• fungal infection
• persistent bacteraemia
• myocardial abscess
• unstable prosthetic valve infected