Endocarditis Part 1 Flashcards
infective endocarditis is commonly referred to as….
an infection of the heart valves by various microorganisms after they enter the bloodstream
infective endocarditis is an infection of the heart valves after entry of microorganisms into where?
the bloodstream
define bacteremia
presence of bacteria in the bloodstream
infective endocarditis is an inflammation of what?
the endocardium (the membrane lining the chamber of the heart and the cusps of the heart valves)
TRUE OR FALSE
endocarditis is associated with high rates of morbidity and mortalitiy
true
name some high risk populations for infective endocarditis
IV drug users
prosthetic valves
congenital heart disease
men more than women
older pts over 60
which bacteria is associated with acute endocarditis? what about subacute?
acute - staph aureus
subacute - strep viridians
most patients with ______ infective endocarditis have a preexisting valvular heart disease
subacute
have prsthetic valves or cardiac devices too
indolent vs fulminating
which is acute infective endocarditis vs subacute
indolent (happens over period of time) = subacute
fulminating (happens suddenly) = acute
TRUE OR FALSE
death occurs within days-weeks for acute infective endocarditis
true
for which may the patient have high fevers, WBC and may even be septic and associated with systemic toxicities — acute or subacute infective endocarditis
acute
2 of the HIGHEST risk factors for infective endocarditis
presence of a prosthetic valve
previous endocarditis
true or false
poor dentition and poor oral hygiene are not a risk factor for infective endocarditis
FALSE - THEY ARE
bc there’s a LOT of bacteria in the oral flora. a cut in the mouth can easily introduce these bacteria into the bloodstream and then potentially the heart
3 main “bugs” that cause infective endocarditis
staphylococci (MOST is staph aureus)
streptococci
enterococci
staphylococci are the main “bugs” responsible for infective endocarditis
break this down further
most is coagulase positive (staph aureus) but some is also coagulase negative (staph epidermidis)
streptococci are 1 of the 3 main “bugs” that cause infective endocarditis
name specific subclass of streptococci that is common
strep viridians
true or false
staph, strep, and enterococci are all gram (+)
TRUE
therefore, most of the time a gram positive organism is causing IE, but it’s still possible it could be gram (-) (healthcare exposure) or be a fungi, or polymicrobial
is it possible for the cultures to be negative but there’s still a case of infective endocarditis?
YES
we can’t isolate the organism but everything else is matching to IE
which 3 valves can be affected by infective endocarditis and for which is it the most common
which is most commonly infected in IV drug users
mitral valve (most common)
aortic valve
tricuspid valve (IV drug users)
true or false
a vegetation can form in any heart valve
TRUE
2 SPECIFIC clinical presentation features of infective endocarditis
HALLMARK OF IE - LAB FINDING
fever and heart murmurs
lab finding - continuous bacteremia
in general, IE should be suspected in any patient who has……
-documented fever + heart murmur
some peripheral manifestations of infective endocarditis
Osler’s nodes
Janeway’s lesions
Roth’s spots
clubbing of the fingers
emboli
splinter hemorrhages
osler node vs janeway lesion
osler’s nodes are painful and theyre on the pads of the fingers and toes
janeway lesions are PAINLESS plaques on the palms of hands or soles of the feet
both are the result of embolism
explain what roth spots are
retinal infarcts that are the result of infective endocarditis
what are splinter hemorrhages
peripheral manifestation of IE
on the nails
clubbing of the nails is typically observed in what endocarditis
long-standing
a nonspecific lab finding in infective endocarditis will be leukocytosis with ______ shift
left
differentiate between the 2 echocardiograms
TTE (transthoracic echo) is less sensitive (high chance of false negatives - may not catch all cases) but it’s easy to do at bedside and you don’t have to fast
TEE (transesophageal echo) has a HIGHER sensitivity (better at finding IE) but you have to fast and it’s more expensive and invasive
what is the “diagnostic tool” for infective endocarditis
the modified duke criteria
combines clinical findings, lab findings, and echo findings
according to modified duke criteria, 2 major criteria is considered…
DEFINITE IE
1 major + 1 minor criteria is considered…..
possible IE
3 minor criteria is considered….
possible IE
5 minor criteria is considered…..
definite IE
name 3 MAJOR criteria
-blood culture positive for IE
-echocardiogram positive for IE
-new valvular regurgitation
goals of therapy to treat infective endocarditis
-relieve signs and symptoms
-decrease morbidity and mortality
-eradicate bacteria
-give appropriate antimicrobial therapy
-prevent from reoccuring in certain high risk patients (antimicrobial prophylaxis)
true or false
managing infective endocarditis is not a team approach
FALSE – it is
involves cardiologists, cardiac surgeons, and specialists in infectious disease
explain the type of antibiotics given in infective endocarditis (ie - dose, route, length of time)
HIGH DOSE parenteral (IV) bactericidal
given for MINIMUM 4-6 weeks (prolonged duration)
surgery in endocarditis is performed often or no?
in around 50% of patients to remove the vegeation
they can get the valve removed and replaced
3 indications for surgery in an endocarditis patient
heart failure
large vegetations
persistent bacteremia and antibiotics aren’t working
name 2 subgroups of streptococci that cause endocarditis
are they part of normal flora?
streptococci viridans (normal flora of the mouth and gingiva)
streptococcal gallolyticus (normal flora of the gut)
streptococcal species are a common cause of endocarditis involving native valves or prosthetic valves?
native valves
usually, infective endocarditis caused by streptococcal species is acute or subacute?
what does this say about the cure rate?
subacute
very high cure rate - 95%
which streptococcal species is associated with GI pathology, especially colon carcinoma
streptococcus gallolyticus – normal flora of the gut
non-enterococcal Group D strep
patient has native valve endocarditis from streptococcal species
name 5 therapy options, assuming the species is HIGHLY SUSCEPTIBLE to penicillin
Penicillin G IV for 4 weeks
Ceftriaxone IV for 4 weeks
Penicillin G IV + Gentamicin IV for 2 weeks
Ceftriaxone IV + Gentamicin IV for 2 weeks
THIS 2 WEEK REGIMEN IS NOT FOR EVERYONE
Vancomycin IV for 4 weeks
ONLY IF UNABLE TO TOLERATE PENICILLIN OR CEFTRIAXONE
as mentioned, the 2 week regimen for streptococcal native valve endocarditis is not for everyone
name 5 pt profiles in which this 2 week therapy is not recommended
over 65
children
impairment of 8th cranial nerve
creatinine clearance less than 20 mL/min
cardiac or extracardiac ascess
what is target AUC for vanco?
what is target trough?
AUC - 400-600
trough 15-20mcg/mL
why is gentamicin combined with penicillin G/ceftriaxone in some scenarios
for SYNERGY
gives more rapid killing
patient has native valve endocarditis from streptococcal species
what are potential antimicrobial agents, if the sample is relatively resistant to penicillin??
what about resistant?
relatively resistant:
Pen G (4 weeks) + gentamicin IV (for initial 2/4 weeks)
ceftriaxone (4 weeks) + gentamicin IV (for initial 2/4 weeks)
or vanco IV for 4 weeks (only if unable to tolerate pen or ceftriaxone)
IF RESISTANT - FOLLOW TREATMENT FOR ENTEROCOCCAL ENDOCARDITIS
Target gentamicin trough and peak
trough less than 1 mcg/mL (otherwise - toxicity)
peak of 3-4 mcg/mL - shows efficacy
Pt has PROSTHETIC valve endocarditis caused by streptococcal species
what are potential therapies assuming highly susceptible to penicillin
Penicillin G IV 6 weeks
Ceftriaxone IV 6 weeks
Vancomycin IV 6 weeks (if can’t tolerate pen or ceftriaxone)
Pt has PROSTHETIC valve endocarditis
what are potential therapies assuming relatively resistant to penicillin?? what about resistant?
relatively resistant:
Pen G + Gentamicin IV ALL for FULL 6 WEEKS
ceftriaxone IV + Gnetamicin IV ALL FOR FULL 6 WEEKS
OR
Vancomycin IV for 6 weeks (if can’t tolerate pen or cef)
if resistant, follow treatment for enterococcal endocarditis
*pt is 72 with streptococcal endocarditis on native heart valve.
MIC < 0.12mcg/mL
NKA
what regimen is appropriate
MIC < 0.12mcg/mL means highly susceptible to penicillin
Ceftriaxone IV for 4 weeks or Penicillin G IV for 4 weeks
NO REASON TO GIVE VANCO AND NOT INDICATED FOR 2 WEEK THERAPY WITH GENTAMICIN
pt is 50 with streptococcal endocarditis on a PROSTHETIC heart valve.
MIC less than 0.12mcg/mL
NKA and good renal function
what is appropriate regimen
Penicillin G IV for 6 Weeks OR Ceftriaxone IV for 6 weeks
NO INDICATION FOR VANCO AND DON’T ADD GENTAMICIN UNTIL RELATIVELY RESISTANT
*Pt is 42 with streptococcal endocarditis on a native valve
MIC is 1 mcg/mL
NKA
what regimen is appropriate
MIC 1mcg/mL means relatively resistant
give Penicillin IV (or ceftriaxone IV) for 4 weeks and gentamicin IV for the initial 2 weeks
Pt is 42 with streptococcal endocarditis on a prosthetic heart valve
MIC is 1mcg/mL
NKA
what regimen is appropriate
Penicillin G/ceftriaxone IV + gentamicin IV for FULL 6 WEEKS
Which bacteria that causes endocarditis is most common among IV drug abusers, those with venous catheters, and valve replacement surgery?
STAPH AUREUS
What MIC is considered relatively resistant to penicillin vs resistant to penicillin
relatively resistant: MIC >0.12-5mcg/mL
resistant: >5mcg/mL
________- are common causes of PROSTHETIC valve endocarditis
staph epidermidis (coagulase negative) and staph aureus (coagulase positive)
coagulase negative staph
staph epidermidis
ALL ________ BACTEREMIA SHOULD BE SCREENED FOR ENDOCARDITIS
staph aureus
which bacteria “loves” prosthetic devices and clumps together on them to form a biofilm?
staph
pt has native valve endocarditis caused by STAPHYLOCOCCI
what is therapy and length if MRSA vs MSSA
MSSA - nafcillin or oxacillin IV for 6 weeks
MRSA - vancomycin IV for 6 weeks
as mentioned, for native valve IV caused by MSSA staph, 1ST LINE IS NAFCILLIN OR OXACILLIN IV FOR 6 WEEKS
what if they are allergic to penicillin?
if NON anaphylactic reaction – can give cefazolin (1st gen)
if anaphylactic reaction to penicillin - use vancomycin
as mentioned, for native valve IE caused by MRSA staph, 1st line is vancomycin IV for 6 weeks
what if the patient can’t tolerate vanco?
can use daptomycin (preferred bc FDA approved) or linezolid
