Endocarditis

Question 1

What is endocarditis

Answer 1

Inflammation of the inner layer of the heart

Question 2

What is the most common cause of endocarditis

Answer 2

Microbial infection

Question 3

Where in the heart does endocarditis normally occur

Answer 3

The valves

Question 4

Give three ways in which microbial infection can enter the bloodstream

Answer 4

Open wound, dental procedure and infected needle

Question 5

What valves are most commonly affected in normal circumstances

Answer 5

Mitral and aortic

Question 6

What valve is most commonly affected in IV drug users

Answer 6

Tricuspid

Question 7

What is non bacterial thrombotic endocarditis (NBTE)

Answer 7

When a thrombus forms on the endothelial layer (usually at the valves)

Question 8

How does a NBTE form

Answer 8

Endothelial damage occurs, inflammation and/or injury, expose collagen and tissue factor, platelets and fibrin adhere to this and the thrombus is formed

Question 9

NBTE+bacteraemia=???

Answer 9

Infective endocarditis

Question 10

What is a vegetation

Answer 10

When bacteria cling on to a thrombus

Question 11

What are adhesins

Answer 11

Substances produced by bacteria to allow them to stick to the thrombus and other bacteria

Question 12

What is a biofilm

Answer 12

A matrix surrounding the bacteria

Question 13

Bacteria attach to high pressure areas

Answer 13

False. Low pressure

Question 14

What is the most common bacteria cause of endocarditis

Answer 14

viridins streptococci

Question 15

Describe viridins streptococci

Answer 15

Low virulence, found in mouth, attack previously damaged heart valves, small vegetation and do not destory heart valves

Question 16

What is the most common bacteria cause of endocarditis in IV drug user

Answer 16

Staphylococcus aureus

Question 17

Describe staphylococcus aureus

Answer 17

High virulence, found in skin, attack healthy and damaged valves, large vegetation and destroy the heart valve

Question 18

Describe staphylococcus epidermis

Answer 18

Common in prosthetic valves from previous valve surgery, commonly infects IV catheter and is noscomial

Question 19

Decribe enterococcus faecalis and streptococcus bovis

Answer 19

Normal gut flora and in a patient with UC or colorectal cancer they can migrate across the gut lining and into the bloodstream

Question 20

Describe coxiella burnetti

Answer 20

From infected animals and causes Q-fever. This Q-fever can potentially cause endocarditis (months or years later). Usually occurs in patient with high risk factors (immunocomprimised, pregnant, valve defects)

Question 21

What are the HACEK organisms

Answer 21

Haemophilus, aggregatibacter, cardiobacterium, eikenella, kingella

Question 22

Describe HACEK organisms

Answer 22

Gram negative, normal mouth and throat flora

Question 23

What signs of endocarditis do septic emboli cause

Answer 23

Splinter haemorrhages (nails) and janeways lesions (fingers and toes)

Question 24

What signs of endocarditis do antigen-antibody complex cause

Answer 24

Fingers and toes: Oslers nodes, eyes: roth spots, kidneys: glomerulonephritis

Question 25

What are painful: Janeways lesions or oslers nodes

Answer 25

Olsers nodes

Question 26

Other symptoms for endocarditis

Answer 26

Fever and turbulent blood flow murmur

Question 27

Diagnosis of endocarditis

Answer 27

Positive blood culture and echocardiogram (shows vegetation)

Question 28

Treatment

Answer 28

Antibiotics or surgery (if severe for examples heart failure)

Question 29

Prevention of endocarditis

Answer 29

If high risk then antibiotics before dental procedures

Question 30

Describe libman-sacks endocarditis

Answer 30

Not infection related but related to SLE. The mitral valve is the most commonly affected valve and causes regurgitation. It can also occur on the chordae tendinae, atrial walls and ventricle walls.