Loading....
Coupon Accepted Successfully!

Medicine

Open Flashcards

Cardiology

Question
5 out of 18
 

A patient has prosthetic valve replacement and he develops endocarditis 8 months later. Organism responsible is? (AIIMS Nov 2010)


A S. aureus

B Coagulase negative staphylococci (CoNS)

C Strep. viridans

D HACEK organism

Ans. B

S. epidermidis

Causes Bacteria:

Any cause of bacteriemia exposes valves to the risk of bacterial colonization (dentistry; UTI; urinary catheterization; cystoscopy; respiratory infection; endoscopy colon cancer; gall bladder disease; skin disease; IV cannulation; surgery; abortion; fractures). Q

1. Staph aureus is the most common cause.

2. Strep viridans is also a common cause (Note: previously it used to be the most common cause)

3. Others: enterococci; Staph aureus or epidermidis; and microaerophilic streptococci.

4. Rarely: HACEK group of Gram negative bacteria (Haemophilus-Actinobacillus-Cardiobacterium-Eikenella- Kingella) Q (AIIMS May 2008)

5. Coxiella burnetii, Chlamydia.

6. Fungi: Candida, Aspergillus, and Histoplasma.

7. Other causes: SLE (Libman-Sacks endocarditis) Q malignancy.

Extra Edge:HACEK – They are fastidious, slowly growing, gram negative and CO2 for growth (Ref. Hari -18thed, pg-1233)

Etiology – Native valve endocarditis: Mitral valve is the most common valve involved.

Causative organism

1. Most common cause in native valve = Staph aureus

2. Streptococci viridans

3. Streptococcus bovis (Polyp, colon tumors)

4. Enterococci

5. HACEK organisms (Hemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella)


Extra Edge: Hemophilus influenzae is not a part of HACEK group. H. aphrophilus and H. parainfluenzae are the most common Haemophilus species isolated from case of HACEK endocarditis. (AIIMS May 2008)

Prosthetic valve endocarditis (Most common valve involved is aortic valve)

1. Within 2 months of surgery = staph aures

2. After 2 months of surgery = coagulase negative staphylococci (CoNS). (Ref. Hari, 18th ed., Pg-1052)

Note: A patient has prosthetic valve replacement and he develops endocarditis 8 months later. Organism responsible is CoNS.

Endocarditis in I.V. drug abusers (Most common valve involve is = tricuspid)

Causes:

1. Commonest– Staph aureus

2. Pseudomonas aeruginosa

3. Candida

4. Polymicrobial infection is more common.

5. Pseudomonas causes endocarditis in IV drug abuser.


Extra Edge:

1. Most common cause in native valve = Staph aures

2. Most common cause in prosthetic valve = Coagulase negative staph aures

3. Most common cause in IV drug abuser = Staph aures (AIIMS Nov 2009)

Cardiology Flashcard List

18 flashcards
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
11)
12)
13)
14)
15)
16)
17)
18)