Infective Endocarditis

Question 1

Tayside Antibiotic Man

Native valve indolent (Subacute):

Answer 1

Amoxicillin IV 2g 4 hourly + Gentamicin

Question 2

Tayside Antibiotic Man

Native valve severe sepsis (Acute):

Answer 2

Flucloxacillin IV 2g 6 hourly (4 hourly if >85kg)

Question 3

Tayside Antibiotic Man

Prosthetic valve or Suspected MRSA:

Answer 3

Vancomycin IV + Gentamicin

+ when therapeutic vancomycin levels reached add Rifampicin PO 600mg bd

Question 4

ALWAYS check full endocarditis guidance for gentamicin/vancomycin dosing especially if reduced renal function

Answer 4

true

Question 5

Suspected endocarditis

Take appropriate blood cultures and then Start empirical therapy and refer to ID/Microbiology

Answer 5

true

Question 6

The strongest risk factor for developing infective endocarditis is

Answer 6

previous episode of endocarditis

Question 7

Which valve is most commonly affected in IE?

Answer 7

Mitral valve

Tricuspid valve in IVDU

Question 8

Patient group in which makes up 50% of those with IE?

Answer 8

previously normal valves

typically present acutely

Question 9

Infective endocarditis patient groups that get this?

Answer 9

previously normal valves (50%, typically acute presentation)

rheumatic valve disease (30%)

prosthetic valves
congenital heart defects
intravenous drug users (IVDUs, e.g. typically causing tricuspid lesion)
others: recent piercings

Question 10

most common cause of infective endocarditis

Answer 10

Staphylococcus aureus

Question 11

most common cause of infective endocarditis in IVDU

Answer 11

Staphylococcus aureus

Question 12

most common cause of infective endocarditis in developing countries

Answer 12

Streptococcus viridans

Question 13

most common cause of infective endocarditis following prosthetic valve surgery

Answer 13

Staphylococcus epidermidis

usually the result of perioperative contamination

Question 14

most common cause of infective endocarditis following indwelling lines

Answer 14

Staphylococcus epidermidis

Question 15

TWO MONTHS following prosthetic valve surgery most common organism

Answer 15

Staphylococcus aureus

After 2 months the spectrum of organisms which cause endocarditis return to normal

Question 16

endocarditis caused by which organisms is linked with poor dental hygiene or following a dental procedure

Answer 16

Streptococcus viridans

Question 17

The two most notable viridans streptococci are

Answer 17

Streptococcus mitis and Streptococcus sanguinis

Question 18

most common cause of infective endocarditis associated with colorectal cancer

Answer 18

Streptococcus bovis

the subtype Streptococcus gallolyticus is most linked with colorectal cancer

Question 19

non-infective causes of endocarditis

Answer 19

systemic lupus erythematosus (Libman-Sacks)

malignancy - marantic endocarditis

Question 20

Culture negative causes of endocarditis

Answer 20

prior antibiotic therapy
Coxiella burnetii
Bartonella
Brucella

HACEK bacteria

Question 21

HACEK stands for

Answer 21

Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella)

Question 22

Infective endocarditis - which criteria?

Answer 22

Infective endocarditis: Modified Duke criteria

Question 23

Infective endocarditis diagnosed if

Answer 23

pathological criteria positive, or
2 major criteria, or
1 major and 3 minor criteria, or
5 minor criteria

Question 24

Pathological criteria means what?

Answer 24

Positive histology or microbiology of pathological material obtained at autopsy or cardiac surgery (valve tissue, vegetations, embolic fragments or intracardiac abscess content)

Question 25

Major criteria

Answer 25

Positive blood cultures

Evidence of endocardial involvement

Question 26

Major criteria - Positive blood cultures

how many positive blood cultures showing typical organisms consistent with infective endocarditis?

Answer 26

two positive blood cultures showing typical organisms consistent with infective endocarditis

Question 27

typical organisms consistent with infective endocarditis include?

pathogen is less specific include?

Answer 27

typical organisms consistent with infective endocarditis - Streptococcus viridans and the HACEK group

less specific - Staph aureus and Staph epidermidis

Question 28

Major criteria - Positive blood cultures

pathogen is less specific criteria?

Answer 28

persistent bacteraemia from two blood cultures taken > 12 hours apart or

three or more positive blood cultures

Question 29

Major criteria - Positive blood cultures

this includes
positive serology for?

or positive molecular assays for?

Answer 29

positive serology for Coxiella burnetii, Bartonella species or Chlamydia psittaci, or

positive molecular assays for specific gene targets

Question 30

Major criteria - Evidence of endocardial involvement includes?

Answer 30

positive echocardiogram (oscillating structures, abscess formation, new valvular regurgitation or dehiscence of prosthetic valves), or

new valvular regurgitation

Question 31

Minor criteria includes?

Answer 31

predisposing heart condition or intravenous drug use
microbiological evidence does not meet major criteria
fever > 38ºC
vascular phenomena
immunological phenomena

Question 32

List vascular phenomena

Answer 32

major emboli, splenomegaly, clubbing, splinter haemorrhages, Janeway lesions, petechiae or purpura

Question 33

List immunological phenomena

Answer 33

glomerulonephritis, Osler’s nodes, Roth spots

Question 34

Which organism is Poor prognostic factor?

Answer 34

Staphylococcus aureus infection

Question 35

Poor prognostic factor

Answer 35

Staphylococcus aureus infection
prosthetic valve (especially ‘early’, acquired during surgery)
culture negative endocarditis
low complement levels

Question 36

Mortality according to organism

Answer 36

staphylococci - 30%
bowel organisms - 15%
streptococci - 5%

Question 37

Indications for surgery

Answer 37

severe valvular incompetence
aortic abscess
infections resistant to antibiotics/fungal infections
cardiac failure refractory to standard medical treatment
recurrent emboli after antibiotic therapy

Question 38

aortic abscess results in what ECG finding

Answer 38

often indicated by a lengthening PR interval

Question 39

NICE recommends the following procedures do NOT require prophylaxis:

Answer 39

dental procedures
upper and lower gastrointestinal tract procedures
genitourinary tract
upper and lower respiratory tract

Question 40

any episodes of infection in people at risk of infective endocarditis should be investigated and treated promptly to reduce the risk of endocarditis developing

Answer 40

true

Question 41

if a person at risk of infective endocarditis is receiving antimicrobial therapy because they are undergoing a WHAT procedure at a site where there is a suspected infection they should be given an antibiotic that covers organisms that cause infective endocarditis

Answer 41

gastrointestinal or genitourinary