Flashcards in Endocarditis, Myocarditis, Pericarditis Deck (44)
what does the presence of bacteria in the bloodstream indicate?
there is a focus of infection elsewhere in the body
what staphylococcus species is the most likely to infect prosthetic material?
what is infective endocarditis?
infection of the endothelium of the heart valves
what are the 4 main classes of predisposing factors for infective endocarditis?
heart valve abnormality
prosthetic heart valve
what type of heart valve abnormalities predispose to infective endocarditis?
calcification/sclerosis of heart valves (in elderly)
congenital heart disease
post rheumatic fever
what is the pathogenesis of infective endocarditis?
1. heart valve damaged
2. turbulent blood flow over roughened endothelium
3. platelets/fibrin depositis forming a thrombi
4. bacteraemia (possibly transient)
5. organisms settle in fibrin/platelet thrombi becoming a microbial vegetation
what is the most common side of the heart to be affected?
(mitral and aortic valves)
what are the 4 main organisms causing endocarditis of native valves?
what are the 3 classes of unusual organisms that can cause endocarditis?
atypicals (eg chlamydia psittaci, coxiella burnetii)
what is the presentation of acute endocarditis?
overwhelming sepsis and cardiac failure
what is the presentation of subacute endocarditis?
what are the sings on examination of infective endocarditis?
Murmur (new or changing)
Nail (splinter) haemorrhages
+ finger clubbing, splenomegaly
what can present in the urine of a patient with infective endocarditis?
how do you diagnose infective endocarditis?
take 3 sets of blood cultures before antibiotics
why must you take 3 sets of blood cultures for diagnosing infective endocarditis?
to ensure you haven't just identified a contaminent
if you suspect infective endocarditis but all 3 blood cultures are negative what should you do?
consider serology for 'atypical' organisms
what are the 2 types of prosthetic valve endocarditis?
what is early prosthetic valve endocarditis?
infected at time of valve insertion
what is late prosthetic valve endocarditis?
up to many years after valve insertion
what are the main causative organisms of early prosthetic valve endocarditis?
what are the causative organisms of late porsthetic valve endocarditis?
what sided infective endocarditis to IVDUs usually get?
(mainly tricuspid valve)
what is the usual causative organisms in a IVDU who has infective endocarditis?
what does infective endocarditis in an IVDU often present as?
as staph aureus pneumonia
what is the empirical treatment for native valve endocarditis infective endocarditis? (ie before microbiology results come back)
benzylpenicillin and gentamicin
what is the empirical treatment for prosthetic valve endocarditis? (ie before microbiology results come back)
vanomycin and gentamicin
what is the empirical treatment for drug use endocarditis? (ie before microbiology results come back)
what is the antibiotic treatment for infective endocarditis where microbiology results show staph aureus (not MRSA) is the causative organism?
what is the antibiotic treatment for infective endocarditis where microbiology results show MRSA is the causative organism?
vancomycin and gentamicin