Infective endocarditis Flashcards
What is infective endocarditis?
Condition caused by infection of the endocardium of the heart
What structure is most commonly affected by infective endocarditis?
The mitral valve
What is the most common bacterial cause of infective endocarditis?
Staphylococcus aureus
What is the most common cause of infective endocarditis in developing countries?
Streptococcus viridians
What are risk factors for infective endocarditis?
rheumatic valve disease
prosthetic valves
congenital heart defects
intravenous drug users
How is infective endocarditis diagnosed?
Via the Modified Duke criteria
What is the Modified Dukes criteria?
Infective endocarditis diagnosed if pathological criteria positive, or 2 major criteria, or 1 major and 3 minor criteria, or 5 minor criteria
What are the pathological criteria for the diagnosis of infective endocarditis?
Positive histology or microbiology of pathological material obtained at autopsy or cardiac surgery
What are the major criteria for the diagnosis of infective endocarditis?
Positive blood cultures more than 12 hours apart
Evidence of endocardial involvement
What are the minor criteria for the diagnosis of infective endocarditis
predisposing heart condition
Intravenous drug use
fever > 38ºC
vascular phenomena:
immunological phenomena
What are examples of endocardial involvement that are suggestive of infective endocarditis?
Positive echocardiogram (oscillating structures, abscess formation, new valvular regurgitation or dehiscence of prosthetic valves), or New valvular regurgitation
Which valve is typically affected in IV drug users affected by infective endocarditis?
Tricuspid valve
What are the 2 main signs that would suggest infective endocarditis?
A new murmur AND a fever
What is the first line imaging investivgation (and most sensitive)`for infective endocarditis?
Transthoracic echocardiogram
What might you find on an echocardiogram that would suggest Infective emdocarditis?
Vegetation
Abscess
Partial dehiscence of prosthetic valve
New valvular regurgitation
What is the management of infective endocarditis?
Long term IV antibiotic therapy
How long shoudl antibiotics be given for infective endocarditis?
Minimum 6 weeks
What antibiotics can be given initially if it is a native valve before the infective cause is diagnosed?
Amoxicillin +/-low-dose gentamicin
If penicillin allergic
vancomycin + low-dose gentamicin
What antibiotics can be given initially if it is a prosthetic valve before the infective cause is diagnosed?
vancomycin + rifampicin + low-dose gentamicin
What is the management of Native valve endocarditis caused by staphylococci?
Flucloxacillin
Vancomyin and rifampicin if penicillin allergic
What is the management of Prosthetic valve endocarditis caused by staphylococci?
Flucloxacillin + rifampicin + low-dose gentamicin
vancomycin + rifampicin + low-dose gentamicin
What are indications for the surgical management off infective endocarditis?
severe valvular incompetence
aortic abscess (often indicated by a lengthening PR interval)
infections resistant to antibiotics/fungal infections
cardiac failure refractory to standard medical treatment
recurrent emboli after antibiotic therapy
What vascular phenomena are included in the minor criteria infective endocarditis?
Major emboli
Splenomegaly
Clubbing
Splinter haemorrhages
Janeway lesions
Petechiae
Purpura
What immunological phenomena are included in the minor criteria for infective endocarditis?
Glomerulonephritis
Osler’s nodes
Roth spots
