Cardiac: Endocarditis Flashcards
What is endocarditis? what usually causes it
- inflammation of endocardium that lines the surface of cardiac valves
- bacterial infection
What is the most common overall cause of endocarditis? and what does it infect
Streptococcus viridans : low-virulence organism that infects previously damaged valves
What diseases involve Streptococcus viridans
- chronic rheumatic heart disease
- mitral valve prolapse
Streptococcus viridans results in what
subacute endocarditis: small vegetations do not destroy valve
- damaged endocardial surface develops thrombotic vegetations
- transient bactermia leads to trapping of bacteria in the vegatations
what can decrease the risk of endocarditis from streptococcus viridans
prophylactic antibiotics
- ex. dentist office
what bacteria is the most common cause of endocarditis in IV drug abuser
Staphylococcus aureus
endocarditis from staphylococcus aureus presents how? which valve does it usually attack
- high virulence organism that infects normal valves
- most common valve tricuspid
- results in large vegetations that destroy the valve ( acute endocarditis)
Endocarditis of prosthetic valves is associated with what bacteria
Streptococcus epidermidis
What bacteria is associated with endocarditis in patients with underlying colorectal carcinoma
Streptococcus bovis
what bacteria is associated with endocarditis with negative blood culture
HACEK
what does HACEK organisms stand for
Haemophilus Actinobacillus Cardiobacterium Eikenella Kingella
What are 4 clinical features of bacterial endocarditis ? and why do we see them?
- fever - due to bacteremia
- murmur - due to vegetations on heart valve
- Janeway lesion, Osler nodes, splinter hemorrhages in nail bed, Roth spots - due to embolization of septic vegetations
- anemia of chronic disease - due to chronic inflammation
Janeway lesion?
erythematous nontender lesions on palms and soles
Osler nodes?
tender lesions on fingers and toes
What are laboratory findings of endocarditis
- positive blood cultures
- Anemia of chronic disease
- Transesophageal echocardiogram is useful for detecting lesions on valves