Infective Endocarditis Case Studies Flashcards
What are key risk factors for infective endocarditis?
abnormal heart valves and risk of bacteremia
Aberrant flow results in platelet-fibrin thrombus on injured
Bacteria enter bloodstream through skin or mucosal surfaces and adhere to thrombus
What predisposing heart conditions can increase chance of getting IE?
prosthetic valves
mitral prolapse w/ regurg or thickened leaflets
Rheumatic heart disease
Complex congential heart
mitral regurg/ AS/ aortic regurg/ ventricular septal defect
What procedures can predispose you to IE?
Dental work or poor hygiene- especially associated w/ bleeding
Hemodialysis
IV drug use (Right sided especially)
Focal infection with typical organism
What are common clinical presentations for IE?
Almost always fever, and heart murmur. Often have chills and sweats with occasional anorexia/malaise
Lab abnormalities and non-cardiac manifestations 5-50%
What noncardiace manifestations appear with IE?
Emolic events 25-50% time… often to CNS (extremeties/spleen or kidneys)
Splenomegaly, clubbing, petechiae less common
What peripheral manifestations are seen with IE?
Splinters hemorrhages in the finger nails
Oslers
Janeways
Roths
When are Splinter hemorrhages more concerning for IE?
when they are proximal or mid nail and more if they are red/purple (opposed to brown)
tender violaceious subQ nodes in the fingers or toes. D/t inflammation and immune complexes
Osler nodes
nontender erythematous or hemorrhagic macules or papules in fingertips, palms or soles dt septic emboli
Janeway lesions seen in IE
What are roth spots?
retinal lesions–hemorrhagic with white central spot, immunologic process seen in IE
What key lab anormalities do we see in IE
anemia 70-90% time
leukocytosis 20-30% time
microscopic hematuria 30-50%
and elevated sed rate and CRP
Most common organisms in IE in acute cases:
Staphylococcus aureus
Most common organisms in IE in prosthetic valves :
coagulase-negative Staph
Most common organisms in IE in elderly:
Enterococcus sp.
Most common organism in IE in a native valve
streptococci
Most common organism in IE in early prosthetic valve replacement:
Coag-Neg staph or possibly staph aureus, but not steptoccocci in early valve replacement (more common for a native valve)
Most common organism in IE in late prosthetic valve replacement:
streptococci (almost same as it would be for native)
Your patient has IE and you identify the causitive agent as strep bovis, what else should you be concerned about?
assoc. with colonic lesions
Are gram - rods or fungi associated with IE?
not usually but if they are more likely due to prosthetic valve or IV drug users
S. aureus, Candida parapsilosis and pseudomonas are causitive IE agents seen in which patients?
IV drug users
Your patient has an elevated fever, chills and weight loss. You hear a murmur and strongly suspect IE after you see evidence in the echo. You take cultures but the cultures are negative… what would you change your DDx to?
don’t necessarily… some IE can be ‘culture-negative’
What are our common ‘culture negative’ causitive agents of endocarditis
Haemophilus Actinobacillus Cardiobacterium Eikenella Kingella HACEK
which is more sensitive for evaluating prosthetic valves, perivalvlar exctension, myocardial abcesses, fistulas and valve perfs?
Transthoracic or transesophageal
Transesophageal echo or TEE
echo that is rapid and noninvasive but sensitivity is less then 70%
Transthoracic echo or TTE
Echo that is sensitive up to 95%
transesophageal or TEE
How do you make a diagnosis of IE?
based on clinical, lab and echo criteria; Modified Duke criteria of 2 major or one major plus 3 minor
Major Duke criteria to Dx IE
Microorganism from 2 seperate blood cultures
–if its an unusual IE organism has to be persistantly positive
-or positieve serology C.burnetti
Evidence of endocardial involvement; new vavlular regurg or positive echocardiogram
Minor Duke criteria to Dx IE
Predisposition: heart abnormalities or IV use
Fever
Vascular phenomena: excluding petechiae or splinter
Immunologic phenomenoa; RH factor, Oslers or Roths
Because bacteria are in vegitative configuration in IE, what do we need to do in therapy to overcome that?
must have PROLONGED and bacteriaCIDAL therapy
(bc they are metabolically inactive and inaccessible to host)
***MUST KILL EVERY BACTERIUM
Rx for penicillin susceptible IE caused by streptococcis
Penicillin or Ceftriaxone x4-6wks
with Vanco x 5-6 weeks
Rx for intermediate penicillin susceptible IE caused by streptococcis
Pen or Ceph x 4-6 wks with Gent x 2-6 wks
– Vancomycin x 4-6 wks
Rx for IE caused by enterococci
Pen or Amp x 4-6 wks with Gent x 2-6 wks
– Vanco with Gent x 6 wks
Pt has a native heart valve and IE caused by staph… Rx?
Nafcillin or Oxacillin (+/-Gentamicin x 3-5
days)
– Cefazolin (+/- Gentamicin x 3-5 days)
– Vancomycin
PT has a prosthetic heart vavle and IE d/t Staph… Rx?
– Nafcillin or Oxacillin + Rifampin (+/- Gent x 2
wks)
– Vancomycin + Rifampin (+/- Gent x 2 wks)
What Rx do we give patient for IE caused by HACEK?
Ceftriaxone x 4-6 wks
• Amp/sulbactam x 4-6 wks
• Ciprofloxacin x 4-6 wks
What are some possible indications for surgery in patient with IE?
congestive HF, prosthetic valve endocarditis, valve perforation or rupture, new heart block, mult embolic events, uncontrolled infection on appropriate rx
When do we expect to see fever dissipate in pts with IE?
half within 3 days of
starting treatment, 75% within one week
Pt has prolounged fever, a week after they started tx for IE, what are my most likley causitive agents?
more likely associated with S.aurues, GNR, fungi
–see this associated with other complications
What cardiac complications arise as a result of IE?
congestive heart failure, heart block, valve failure, abscess or fistula
What neurologic and systemic complications arise dt IE?
embolic stroke, mycotic aneurysm and menigits
systemically: septic emboli and abcesses
Most common peripheral MCA, usually at bifurcations and more common with virdians step… can be caused by direct emboli or infection of wall or immune complex
Mycotic aneurysms
A patient that has IE asks about prophylaxis so she doesn’t get IE again in the future… how would you educate her?
inform her bacterimia is more likely doing to result from daily activities such as not brushing teeth then from a procedure and that prophylaxis antiB prevent few, if any IE cases thus risk of taking vs not need to be weighed.
MAITAIN ORAL HYGIENE!!!!!
Pt has several surgeries scheduled for the next few months. He has a scaling and root planing appointment with his hygenist and then an endoscopy. Which appts does he need to premedicate with if he had previous IE?
for the scaling and planing
not for GI or GU
Recommended pre-med for dental appointments that involve gingiva or perforation or oral mucosa
Dental—single dose, 30-60 min before – Amoxicillin 2 grams PO – Clindamycin 600 mg – Ampicillin 2 grams IV – Ceftriaxone 1 gram IV
