Infective Endocarditis Flashcards
Define infective endocarditis
Refers to infection of the endothelium (inner surface of the heart), most commonly affecting the heart valves
Which heart valve is most commonly affected in infective endocarditis?
Mitral valve
Give 5 risk factors for infective endocarditis
IV drug users
Structural heart pathology (i.e valve disease)
Prosthetic heart valves
CKD (particularly on dialysis)
Immunocompromise (cancer, HIV, immunosuppressive medications)
Which valve is commonly affected by infective endocarditis in IV drug users?
Tricuspid valve
What the most common bacterial cause of infective endocarditis?
Staphylococcus aureus
What is the most common cause of infective endocarditis in IV drug users?
Staphylococcus aureus
What is the most common bacterial cause of infective endocarditis in patients with poor dental hygiene?
Streptococcus viridans
What is the most common bacterial cause of infective endocarditis in patients following prosthetic heart valves? (2)
< 2 months - Staphylococcus epidermidis
> 2 months - Staphylococcus aureus
Give 5 presenting features of infective endocarditis
Fever
Fatigue
Nightsweats
Muscle aches
Anorexia (loss of appetite)
Give 5 examination findings for infective endocarditis
New/changing heart murmur
Splinter haemorrhages (lines on fingernails)
Petechiae (non-blanching red/brown spots on trunk, limbs, oral mucosa or conjunctiva)
Janeway lesions (painless red on palms)
Oslers nosed (painful on fingers/toes)
Name 4 investigations for infective endocarditi
Blood cultures BEFORE starting antibiotics - 3 blood cultures taken separated by 3 hours, taken from different sites.
Transoesophageal echocardiography (TOE)
SPECT-CT - Used in patients with prosthetic heart valves
How does the modified duke criteria diagnose infective endocarditis?
One major + 3 minor criteria OR 5 minor criteria
What criteria is used to diagnose infective endocarditis?
Modified Duke criteria
Name 2 major criteria for infective endocarditis (modified duke criteria)
Persistently positive blood cultures (bacteria seen on multiple cultures)
Specific imaging findings (vegetation/regurgitation seen on echocardiogram)
Name 5 minor criteria for infective endocarditis (modified dukes criteria)
Predisposition (IVDU or heart valve pathology)
Fever (over 38)
Vascular phenomena (splenic infarction, Intracranial haemorrhage, janeway lesions)
Immunological phenomena (osler’s nodes, roth spots, glomerulonephritis)
Microbiological phenomena (positive cultures not qualifying as a major criteria)
