most common bacteria of endocarditis
-other important bacteria (4)
- Strep viridans–subacute endocarditis
- low virulence, can only infect previously damaged valves (eg from rheumatic fever or mitral valve prolapse) - Staph A–high virulence. most common in IV drug users.
- Staph epidermidis (prosthetic valves)
- Strep bovis
- HACEK organisms (hemophilus, actinobacillus, cardiobacterium, eikenella, kingella)–have negative culture b/c hard to grow
what happens in endocarditis
- damaged endocardial surface develops thrombotic vegetations
- bacteria can get trapped in vegetations and cause more vegetation formation
If you identify strep bovis as a cause of endocarditis, suspect what else?
Colorectal cancer.
strong association
What lesions might you find on a pt during physical exam if he has endocarditis? (4)
1-3 caused by septic emboli, #4 caused by deposition of immune complexes
- Janeway lesions
- erythematous, nontender on palms, soles - Splinter hemorrhages in nails, caused by septic vegetation emboli
- Roth spots
- spots on retina, caused by septic vegetation emboli - Osler nodes
- tender, on fingers, toes
(“Ouch ouch Osler” to differentiate from Janeway lesions)
Pt is dx wth endocarditis. You do culture but it is negative.
What possible causes do you suspect?
- Infection with HACEK organism
(hemophilus, actinobacillus, cardiobacterium, eikenella, kingella–hard to culture, can be negative)
- Nonbacterial thrombotic endocarditis (associated with hypercoagulable state or adenocarcinoma)
- Libman-Sacks endocarditis (SLE)
Nonbacterial thrombotic endocarditis
- sterile vegetations, can cause mitral regurg
- associated with hypercoagulable state or adenocarcinoma
Libman-Sacks endocarditis
- sterile vegetations on both sides of mitral valve (very characteristic)
- associated with SLE
If you see vegetations on both sides of the mitral valve, what do you suspect?
- Libman-Sacks endocarditis
- characteristic finding
- associated with SLE
