Infective Endocarditis

Question 1

What is Subacute endocarditis and what is a common cause?

Answer 1

Subacute endocarditis is more common and symptoms develop over a longer period of time and it is classically caused by the viridans Streptococci.

Question 2

What is Acute endocarditis and what population is typically affected?

Answer 2

Acute endocarditis progresses very rapidly with more severe symptoms. It was classically associated with infection caused by Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae or Neisseria gonorrhoeae and is common in intravenous (IV) drug users

Question 3

What are the 4 most common organisms that cause endocarditis?

Answer 3

• Viradans Streptococci
• Enterococci
• Other Strep (S. pyogenes)
• S. aureus

Question 4

What patient populations with IE are most affected with Strep viridans?

Answer 4

Children and patients with mitral valve prolapse

Question 5

What is the most common cause of IE?

Answer 5

S. aureus

Question 6

What is the most common cause of IE in patients with prosthetic heart valves?

Answer 6

S. epidermidis

Question 7

Splinter Hemorrhages

Answer 7

Splinter hemorrhages are linear red to brown streaks that appear under the fingernails and toenails.

Question 8

Janeway Lesions

Answer 8

Janeway lesions are small erythematous nodules observed on the palms and soles.

Question 9

Osler Nodes

Answer 9

Osler nodes are erythematous wheal-like tender nodules 2-15 mm in diameter and are usually located on the pads of fingers and toes.

Question 10

Petechiae from IE

Answer 10

Petechia from IE occurs in crops or batches, especially in the conjunctivae, buccal mucosa or palate, upper chest and extremities.

Question 11

Roth Spots

Answer 11

Round or oval retinal hemorrhages with pale centers

Question 12

What are some of the cardiac signs of endocarditis?

Answer 12

Key signs include valvular insufficiency, a change in a pre-existing murmur or a new cardiac valvular murmur, and tachycardia

Question 13

What usually precedes endocarditis?

Answer 13

Endocarditis is usually preceded by damage to the endothelium inside the heart and or the heart valve

Question 14

How does damage to the heart or the heart valve eventually lead to endocarditis?

Answer 14

As a result of the tissue damage there is an accumulation of platelets and fibrin, producing a nonbacterial thrombotic endocarditis (NBTE). IE results when the lesion serves as a site for microorganisms from the blood stream to attach.

Question 15

What are some symptoms that lead to suspicion of IE?

Answer 15

Fever with a murmur

Question 16

What are the 2 major studies to confirm IE?

Answer 16

Blood cultures and echocardiography

Question 17

What is the most sensitive study for detecting valvular vegetations?

Answer 17

Transesophageal echocardiography (TEE)

Question 18

What is the first lab that should be done when IE is suspected?

Answer 18

Blood culture

Question 19

What are the 2 major criteria for IE?

Answer 19

If there is good bacterial growth from more than one of blood samples (major criteria 1) and if damage to heart valves is detected by echocardiograph (major criteria 2) then IE is confirmed.

Question 20

What are the 5 minor criteria for IE?

Answer 20

1. Predisposing heart disease or intravenous drug use
2. High body temperature
3. Evidence of vascular phenomena
4. Immunological phenomena including Glomerulonephritis, Osler nodes, Roth spots, Rheumatoid factor
5. Microbiologic evidence: defined as a single positive blood culture that does not meet the third major criterion, or serologic evidence of an active infection with an organism consistent with IE.

Question 21

What is the most common treatment for IE?

Answer 21

Penicillin G with an Aminoglycoside like gentamicin

- Vancomycin can be substituted in cases of allergy to penicillin