EXAM #2: SKIN & SOFT TISSUE/ BONE & JOINT INFECTIONS Flashcards Preview

Infectious Disease > EXAM #2: SKIN & SOFT TISSUE/ BONE & JOINT INFECTIONS > Flashcards

Flashcards in EXAM #2: SKIN & SOFT TISSUE/ BONE & JOINT INFECTIONS Deck (39):
1

What two common pathogens cause impetigo?

1) S. pyogenes
2) S. aureus

2

What is the most common pathogen to cause erysipelas?

S. pyogenes

3

What is the most common pathogen to cause folliculitis and furuncles?

S. aureus

4

What are the most common pathogens to cause cellulitis?

1) S. pyognes
2) S. aureus

5

What causes hot-tub folliculitis?

Pseudomonas aeruginosa

6

What is the gram-stain of pseudomonas?

Gram-negative

7

Is pseudomonas a cocci or baccilus?

Bacillus (rod)

8

You are seeing an elderly patient s/p CABG 1-year prior. Today he has cellulitis in the area of the great saphenous vein graft. What are you concerned about?

This is a ssociation with lymphedema, which is a nidus for infection

9

In a wrestler with a large abscess and surrounding cellulitis, what organism are you concerned about?

MRSA

10

What is the indication for anti-microbials after I/D of an abscess?

Surrounding cellulitis

11

What is the treatment for uncomplicated non-purulent cellulitis?

First ask yourself if there is a risk for MRSA?
- No= Cefazolin* i.e. cephalosporin
- Yes= Vancomycin

12

What is the treatment for uncomplicated purulent cellulitis?

1) I/D
2) Vancomycin

13

What is the treatment for hot tub folliculitis?

None

14

What are the organisms that cause Necrotizing Fasciitis? What notable organism rarely cause Nec. Fas?

1) Clostridium perfringens
2) Group A strep
3) Polymicrobial

*Note that MRSA is rare

15

What are the clinical features of Necrotizing Fasciitis?

1) Severe constant pain out of proportion to PE
2) Bullous lesion
3) Systemic toxicity
4) Gas in soft tissue
5) Rapid spread

16

What historical features are associated with Clostridium perfringes causing nec. fas?

- Tissue tramua
- Surgery

17

What gram stain is C. perfringes?

Gram negative

18

What is sporotrichosis associated with?

Rose-gardening

*"Marching along the lymphatics"

19

What is the most common etiology of septic arthritis?

Hematogenous spread* most common

20

What are the risk factors for septic arthritis?

1) RA
2) Steroid use
3) DM

21

What organism most commonly causes septic arthritis?

S. aureus

*Followed by Steptococci and gram negative bacteria

22

What organisms most commonly cause septic arthritis if there is a prosthetic joint?

Coagulase negative Staph (S. epidermidis)

23

What is the most common viral cause of septic arthritis?

Parvovirus B19

24

What are the clinical manifestations of septic arthritis?

- One joint (knee is most common)
- Pain, swelling, redness, warmth
- Fever
- Limited use/ ROM

25

How is aseptic vs. septic arthritis distinguished?

1) Septic is more commonly associated with WBC greater than 60,000
2) Septic will have positive cultures

26

How is septic arthritis treated?

1) Systemic antibiotics
2) Drain infected joint

27

In sexually active young adults/adults, what is the most likely cause of septic arthritis?

Neisseria gonorrhea

28

How is N. gonorrhea septic arthritis treated?

Ceftriaxone (3rd generation cephalosporin)

29

How is S. aureus septic arthritis treated?

Nafcillin or Vancomycin

30

How is GAS septic arthritis treated?

PCN

31

How is gram negative septic arthritis treated?

Cephalosporin

32

How long are patients with septic arthritis placed on abx?

2-4 weeks

- 2 weeks for N. gonorrhea
- 4 weeks for S. aureus

33

What are the possible etiologies of osteomyelitis?

1) Hematogenous= distant focus
2) Contiguous= adjacent spread from soft tissue
3) Direct= surgery/trauma

34

What time frame distinguishes between acute and chronic osteomyelitis?

1 month

35

What is the most common bacteria to cause osteomyelitis?

S. aureus

36

How is osteomyelitis diagnosed?

1) Probe the bone
2) MRI*
3) Bone biopsy

*Preferred*

37

What is the standard of care for imaging possible osteomyelitis?

MRI

38

What is the most common etiology of puncture wound osteomyelitis?

Pseudomonas aeruginosa

39

How do the main treatment modalities change in acute and chronic osteomyelitis?

Acute= Abx then surgery

Chronic= Surgery then abx