[20] Infective Endocarditis Flashcards
Definition: Infective Endocarditis
Microbial infection of the endothelium of the heart
Why are heart valves prone to IE?
Valves do not receive dedicated blood supply
No defensive immune mechanisms
Characteristic Lesion of IE
Vegetation
Define: Nosocomial IE
Infection gained through the hospital stay
[Acute vs. Subacute IE]
Valves Affected
A: Normal Valves
SA: Typically affects only abnormal valves
[Acute vs. Subacute IE]
Course and Time
A: Aggressive course over days
SA: Indolent course over months
[Acute vs. Subacute IE]
Causative Agents
A: S. Aureus and B Streptococci
SA: Enterococci and A Hemolytic Streptococci
[Early PVE vs. Late PVE]
Causative Agents
E: Staph. Epi Coagulase Negative and due to Intraoperative Contamination or Postop Bacterial Contamination
L: Staphylococci, Alpha Hemolytic Streptococci and Enterococci
[IMPORTANT]
Intravenous Drug Abuse IE usually affect which valve?
50% involve the Tricuspid Valve
Most common causative organism of IVDA IE
S. aureus
In Adults over 60 years old, IE is commonly associated with?
> 30% with Calcific Aortic Stenosis
[IMPORTANT]
How many days do we use for “early” or “late” post op for Prothetic Valve IE?
60 Days
What causes 30-65% of Native Valve Endocarditis (NVE) unrelated to drug abuse?
Viridans streptococci
How do you treat Enterococcal IE?
Penicillin (cell-wall active agent) + Gentamycin (Aminoglycoside)
Most commonly associated Etiologic Agent for IE in all populations especially with drug use?
Staphylococcus
Major Cause of PVE during Initial Year After Valve Surgery?
Staphylococcus epidermidis
Gram ( - ) Bacteria Associated with IE
HACEK Organisms
Haemophilus Actinobacillus Cardiobacterium Eikenella Kingella
Pathogenesis Pathway of Infective Endocarditis
- Endothelial Injury
- Hemostasis
- Platelet-Fibrin Complex
- Non-Bacterial Thrombotic Endocarditis
- Bacteremia
- Colonization and Infection of NBTE (Maranthic Endocarditis)
What is the most common Gram (-) Bacteria that Causes IE?
Pseudomonas, with a very high mortality rate
Where are Bacteria and NBTE Vegetation Deposited during IE?
On the sides of the low pressure sink that lie beyond the narrowing or stenosis
Most Common Clinical Features of IE?
Fever 80-90%
Followed by Murmurs 80-85%
Describe: Janeway Lesion
Macular
Blanching
Nontender Lesion
Describe: Osler’s Lesion
Tender
Erythematous
Describe: Roth’s Spots
Retinal hemorrhages with a pale white center
Common Peripheral Manifestations of IE?
Petechiae
Janeway Lesion
Osler’s Lesion
Roth’s Spots
Major Criteria for Duke’s Criteria
- 2 blood cultures positive for organisms found in patients with IE
- Echocardiogram
Are you allowed to wait for blood cultures to come for patients who have been sick for a long time?
Yes, it is not incorrect since they are stable
Prophylaxis/Prevention for IE Mainly Focuses On?
Prevention of Bacteremia to attach to the NBTE
IE Prophylaxis is recommended for?
Dental Procedures that penetrate the mucosa
Any incision involving the respiratory mucosa
IE Prophylaxis is no longer recommended for?
GI or Genitourinary Tract Procedures
Who should receive IE Prophylaxis during Dental Procedures?
Patients with prosthetic cardiac valves
Patients with previous IE
Patients with unrepaired cyanotic CHD
Patients with completely repaired CHD during the first 6 months
Post transplant patients with valve regurgitation
