Endocarditis, Myocarditis, Pericarditis Flashcards
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?
staphylococcus epidermidis
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
IVDU
intravascular lines
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?
- heart valve damaged
- turbulent blood flow over roughened endothelium
- platelets/fibrin depositis forming a thrombi
- bacteraemia (possibly transient)
- organisms settle in fibrin/platelet thrombi becoming a microbial vegetation
what is the most common side of the heart to be affected?
left side
mitral and aortic valves
what are the 4 main organisms causing endocarditis of native valves?
staphylococcus aureus
viridans streptococci
enterococcus sp
staphylococcus epidermidis
what are the 3 classes of unusual organisms that can cause endocarditis?
atypicals (eg chlamydia psittaci, coxiella burnetii)
gram-negatives
fungi
what is the presentation of acute endocarditis?
overwhelming sepsis and cardiac failure
what is the presentation of subacute endocarditis?
fever malasie weight loss tiredness breathlessness
what are the sings on examination of infective endocarditis?
Fever Roth spots Osler nodes Murmur (new or changing) Janeway lesions Anaemia Nail (splinter) haemorrhages Emboli \+ finger clubbing, splenomegaly
what can present in the urine of a patient with infective endocarditis?
(microscopic) haematuria
how do you diagnose infective endocarditis?
take 3 sets of blood cultures before antibiotics
echocardiogram
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?
early
late
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?
staph epidermidis
staph aureus
what are the causative organisms of late porsthetic valve endocarditis?
co-incidental bacteraemia
what sided infective endocarditis to IVDUs usually get?
right sided
mainly tricuspid valve
what is the usual causative organisms in a IVDU who has infective endocarditis?
staph aureus
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
IV
what is the empirical treatment for prosthetic valve endocarditis? (ie before microbiology results come back)
vanomycin and gentamicin
IV
what is the empirical treatment for drug use endocarditis? (ie before microbiology results come back)
flucloxacillin
IV
what is the antibiotic treatment for infective endocarditis where microbiology results show staph aureus (not MRSA) is the causative organism?
flucloxacillin IV
what is the antibiotic treatment for infective endocarditis where microbiology results show MRSA is the causative organism?
vancomycin and gentamicin
IV
what is the antibiotic treatment for infective endocarditis where microbiology results show viridans streptococci is the causative organism?
benzylpenicillin and gentamicin
IV
what is the antibiotic treatment for infective endocarditis where microbiology results show enterococcus sp is the causative organism?
amoxicillin/vancomycin and gentamicin
IV
what is the antibiotic treatment for infective endocarditis where microbiology results show staph epidermidis is the causative organism?
vancomycin and gentamicin
IV
in regards to treatment for infective endocarditis, how long should antibiotics be given for?
4-6 weeks
if antibiotic therapy for infective endocarditis is failing what should you consider?
surgery
what is myocarditis?
inflammation of cardiac muscle
what are the symptoms of myocarditis?
fever
chest pain
SOB
palptations
what are the signs of myocarditis?
pyrexial
arrythmia
cardiac failure
what are the main causes of myocardiis?
enteroviruses- coxsackie A + B, echovirus
other eg influenza
how is myocarditis diagnosed?
viral culture/PCR
throat swab + stool for enteroviruses
throat swab and serology for influenza
what is the treatment of myocarditis?
supportive
what is pericarditis?
inflammation of the pericardium
what is the main feature of pericarditis?
chest pain
what is the treatment of pericarditis?
- supportive if viral cause
- antibiotics and drainage if bacterial cause
what are the 2 main sequellae of infective endocarditis?
valvular heart disease
emboli
