Infective Endocarditis Flashcards
Tayside Antibiotic Man
Native valve indolent (Subacute):
Amoxicillin IV 2g 4 hourly + Gentamicin
Tayside Antibiotic Man
Native valve severe sepsis (Acute):
Flucloxacillin IV 2g 6 hourly (4 hourly if >85kg)
Tayside Antibiotic Man
Prosthetic valve or Suspected MRSA:
Vancomycin IV + Gentamicin
+ when therapeutic vancomycin levels reached add Rifampicin PO 600mg bd
ALWAYS check full endocarditis guidance for gentamicin/vancomycin dosing especially if reduced renal function
true
Suspected endocarditis
Take appropriate blood cultures and then Start empirical therapy and refer to ID/Microbiology
true
The strongest risk factor for developing infective endocarditis is
previous episode of endocarditis
Which valve is most commonly affected in IE?
Mitral valve
Tricuspid valve in IVDU
Patient group in which makes up 50% of those with IE?
previously normal valves
typically present acutely
Infective endocarditis patient groups that get this?
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
most common cause of infective endocarditis
Staphylococcus aureus
most common cause of infective endocarditis in IVDU
Staphylococcus aureus
most common cause of infective endocarditis in developing countries
Streptococcus viridans
most common cause of infective endocarditis following prosthetic valve surgery
Staphylococcus epidermidis
usually the result of perioperative contamination
most common cause of infective endocarditis following indwelling lines
Staphylococcus epidermidis
TWO MONTHS following prosthetic valve surgery most common organism
Staphylococcus aureus
After 2 months the spectrum of organisms which cause endocarditis return to normal
endocarditis caused by which organisms is linked with poor dental hygiene or following a dental procedure
Streptococcus viridans
The two most notable viridans streptococci are
Streptococcus mitis and Streptococcus sanguinis
most common cause of infective endocarditis associated with colorectal cancer
Streptococcus bovis
the subtype Streptococcus gallolyticus is most linked with colorectal cancer
non-infective causes of endocarditis
systemic lupus erythematosus (Libman-Sacks)
malignancy - marantic endocarditis
Culture negative causes of endocarditis
prior antibiotic therapy
Coxiella burnetii
Bartonella
Brucella
HACEK bacteria
HACEK stands for
Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella)
Infective endocarditis - which criteria?
Infective endocarditis: Modified Duke criteria
Infective endocarditis diagnosed if
pathological criteria positive, or
2 major criteria, or
1 major and 3 minor criteria, or
5 minor criteria
Pathological criteria means what?
Positive histology or microbiology of pathological material obtained at autopsy or cardiac surgery (valve tissue, vegetations, embolic fragments or intracardiac abscess content)
Major criteria
Positive blood cultures
Evidence of endocardial involvement
Major criteria - Positive blood cultures
how many positive blood cultures showing typical organisms consistent with infective endocarditis?
two positive blood cultures showing typical organisms consistent with infective endocarditis
typical organisms consistent with infective endocarditis include?
pathogen is less specific include?
typical organisms consistent with infective endocarditis - Streptococcus viridans and the HACEK group
less specific - Staph aureus and Staph epidermidis
Major criteria - Positive blood cultures
pathogen is less specific criteria?
persistent bacteraemia from two blood cultures taken > 12 hours apart or
three or more positive blood cultures
Major criteria - Positive blood cultures
this includes
positive serology for?
or positive molecular assays for?
positive serology for Coxiella burnetii, Bartonella species or Chlamydia psittaci, or
positive molecular assays for specific gene targets
Major criteria - Evidence of endocardial involvement includes?
positive echocardiogram (oscillating structures, abscess formation, new valvular regurgitation or dehiscence of prosthetic valves), or
new valvular regurgitation
Minor criteria includes?
predisposing heart condition or intravenous drug use
microbiological evidence does not meet major criteria
fever > 38ºC
vascular phenomena
immunological phenomena
List vascular phenomena
major emboli, splenomegaly, clubbing, splinter haemorrhages, Janeway lesions, petechiae or purpura
List immunological phenomena
glomerulonephritis, Osler’s nodes, Roth spots
Which organism is Poor prognostic factor?
Staphylococcus aureus infection
Poor prognostic factor
Staphylococcus aureus infection
prosthetic valve (especially ‘early’, acquired during surgery)
culture negative endocarditis
low complement levels
Mortality according to organism
staphylococci - 30%
bowel organisms - 15%
streptococci - 5%
Indications for surgery
severe valvular incompetence
aortic abscess
infections resistant to antibiotics/fungal infections
cardiac failure refractory to standard medical treatment
recurrent emboli after antibiotic therapy
aortic abscess results in what ECG finding
often indicated by a lengthening PR interval
NICE recommends the following procedures do NOT require prophylaxis:
dental procedures
upper and lower gastrointestinal tract procedures
genitourinary tract
upper and lower respiratory tract
any episodes of infection in people at risk of infective endocarditis should be investigated and treated promptly to reduce the risk of endocarditis developing
true
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
gastrointestinal or genitourinary
