Flashcards in Endocarditis Deck (51)
Pathologies of endocarditis
Prototypic Native Valve Endocarditis (NVE) lesion
Non-bacterial Thrombotic Endocarditis (NBTE)
What are NVE lesions made up of?
Mass of platelets, fibrin, microbial microcolonies with scant inflammatory cells
What are NBTE (AKA marantic endocarditis) made up of?
uninfected platelet-fibrin thrombus often a nidus for mocrobial adhesion during bacteremia
Explain the Venturi effect
NBTE and NVE develop on sides of low-pressure sink just beyond the valve or intraventricular defect or stenosis (they glob on)
T/F Cardiac valves have no dedicated blood supply?
What effects does the lack of dedicated blood supply have on cardiac valves?
Host immune response blunted
Limited access of abx
What cardiac locations are involved in endocarditis?
Low-pressure side of ventricular septal deffect
Mural endocardium damaged by aberrant jets
What are the 2 older terms still used in some places to classify endocarditis?
Subacute Bacterial Endocarditis (SBE)
Acute Bacterial Endocarditis
What is the classification system now preferred for endocarditis?
Incubation less than about_____ is considered short incubation?
Inbuation greater than about ______ is considered long incubation?
What are the most common current etiologies of endocarditis?
Congenital heard disease
Illicit IV drug use
Degenerative Valve dz
Incidence notability increased in elderly
What percent of cases of NVE are related to healthcare?
What percentage of endocarditis involves prostehtic valves?
during what time period is a patient with a valve replacement at greatest risk of endocarditis?
What locations on the body can serve as possible soures of infective endocarditis?
upper respiratory tract
What bacteria may result in endocarditis from oral cavity, skin, and upper respiratory tract?
What bacteria may result in endocarditis from GI source?
What bacteria may result in endocarditis from a GU source?
What bacteria may result in endocarditis from a nosocomial source?
CoNS (coag neg staph)
What procedures may result in procedure induced bacteremia?
Transurethral resection of prostate (TURP)
What is the timeline for recognizing a nosocomial infective endocarditis?
Exposure within 90 days
What valve is most commonly involved in endocarditis in an IV drug user? And what pathogens are most common?
Tricuspid-S. aureus, commonly MRSA
What percentage of patient's have negative blood cultures? What is this due to?
5-15% come back negative (33-50% of this is due to premature initiation of tx.)
Pathogenesis of E-carditis (4)
1. Adhesion molecules recognize MSCRAMMS
2. Platelet-fibrin vegetations form dense microcolonies of microbes
3. Organisms deep inside the vegetations are inactive and resistant
4. Surface organisms continuously shed into the blood stream
It is the result of ___________ that causes the symptoms of Endocarditis?
Fighting the infection
What symptoms result from the pathophys of endocarditis?
Constitutional - cytokine production
Damage to intracardiac structure
Embolization of veg fragments - leading to infection or infarction
cadiac presentation of E-card?
murmurs may not start right away but occur eventually in 85%
CHF (30-40%)-from valvular dysfunction
MI-dt emboli (2%)
Classic presentation seen in 50% of endocarditis pt's?
subungual (splinter) hemorrhages