[20] Infective Endocarditis

Question 1

Definition: Infective Endocarditis

Answer 1

Microbial infection of the endothelium of the heart

Question 2

Why are heart valves prone to IE?

Answer 2

Valves do not receive dedicated blood supply

No defensive immune mechanisms

Question 3

Characteristic Lesion of IE

Answer 3

Vegetation

Question 4

Define: Nosocomial IE

Answer 4

Infection gained through the hospital stay

Question 5

[Acute vs. Subacute IE]

Valves Affected

Answer 5

A: Normal Valves

SA: Typically affects only abnormal valves

Question 6

[Acute vs. Subacute IE]

Course and Time

Answer 6

A: Aggressive course over days

SA: Indolent course over months

Question 7

[Acute vs. Subacute IE]

Causative Agents

Answer 7

A: S. Aureus and B Streptococci

SA: Enterococci and A Hemolytic Streptococci

Question 8

[Early PVE vs. Late PVE]

Causative Agents

Answer 8

E: Staph. Epi Coagulase Negative and due to Intraoperative Contamination or Postop Bacterial Contamination

L: Staphylococci, Alpha Hemolytic Streptococci and Enterococci

[IMPORTANT]

Question 9

Intravenous Drug Abuse IE usually affect which valve?

Answer 9

50% involve the Tricuspid Valve

Question 10

Most common causative organism of IVDA IE

Answer 10

S. aureus

Question 11

In Adults over 60 years old, IE is commonly associated with?

Answer 11

> 30% with Calcific Aortic Stenosis

[IMPORTANT]

Question 12

How many days do we use for “early” or “late” post op for Prothetic Valve IE?

Answer 12

60 Days

Question 13

What causes 30-65% of Native Valve Endocarditis (NVE) unrelated to drug abuse?

Answer 13

Viridans streptococci

Question 14

How do you treat Enterococcal IE?

Answer 14

Penicillin (cell-wall active agent) + Gentamycin (Aminoglycoside)

Question 15

Most commonly associated Etiologic Agent for IE in all populations especially with drug use?

Answer 15

Staphylococcus

Question 16

Major Cause of PVE during Initial Year After Valve Surgery?

Answer 16

Staphylococcus epidermidis

Question 17

Gram ( - ) Bacteria Associated with IE

Answer 17

HACEK Organisms

Haemophilus
Actinobacillus
Cardiobacterium
Eikenella
Kingella

Question 18

Pathogenesis Pathway of Infective Endocarditis

Answer 18

1. Endothelial Injury
2. Hemostasis
3. Platelet-Fibrin Complex
4. Non-Bacterial Thrombotic Endocarditis
5. Bacteremia
6. Colonization and Infection of NBTE (Maranthic Endocarditis)

Question 19

What is the most common Gram (-) Bacteria that Causes IE?

Answer 19

Pseudomonas, with a very high mortality rate

Question 20

Where are Bacteria and NBTE Vegetation Deposited during IE?

Answer 20

On the sides of the low pressure sink that lie beyond the narrowing or stenosis

Question 21

Most Common Clinical Features of IE?

Answer 21

Fever 80-90%

Followed by Murmurs 80-85%

Question 22

Describe: Janeway Lesion

Answer 22

Macular
Blanching
Nontender Lesion

Question 23

Describe: Osler’s Lesion

Answer 23

Tender

Erythematous

Question 24

Describe: Roth’s Spots

Answer 24

Retinal hemorrhages with a pale white center

Question 25

Common Peripheral Manifestations of IE?

Answer 25

Petechiae
Janeway Lesion
Osler’s Lesion
Roth’s Spots

Question 26

Major Criteria for Duke’s Criteria

Answer 26

1. 2 blood cultures positive for organisms found in patients with IE
2. Echocardiogram

Question 27

Are you allowed to wait for blood cultures to come for patients who have been sick for a long time?

Answer 27

Yes, it is not incorrect since they are stable

Question 28

Prophylaxis/Prevention for IE Mainly Focuses On?

Answer 28

Prevention of Bacteremia to attach to the NBTE

Question 29

IE Prophylaxis is recommended for?

Answer 29

Dental Procedures that penetrate the mucosa

Any incision involving the respiratory mucosa

Question 30

IE Prophylaxis is no longer recommended for?

Answer 30

GI or Genitourinary Tract Procedures

Question 31

Who should receive IE Prophylaxis during Dental Procedures?

Answer 31

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