SSTI's

Question 1

Appearance of Cellulitis

Answer 1

Usually on the limbs
Red and spreading quickly
Usually due to puncture of some sort

Question 2

Appearance of Erysipelas

Answer 2

Usually on the face

Red and spreading quickly

Question 3

Appearance of Impetigo

Answer 3

Usually on the face
Like cold sores
Small, thick golden crusts = Impetigo contagiosum
Large, thin ligh-brown crusts = Bullous impetigo

Question 4

Appearance of Lymphangitis

Answer 4

Connected through lymphatic system.

Question 5

Appearance of Necrotizing infections

Answer 5

Very painful, and pain extends further than the visible portion of the infection.
Rapidly progressive.

Question 6

Appearance of Bite wounds

Answer 6

Obvious

Question 7

Appearance of Osteomyelitis

Answer 7

Deep infections

Question 8

Appearance of Osteomyelitis

Answer 8

Deep infections, often connected to DM in this module’s context.

Question 9

Erysipelas pathogens

Answer 9

Almost exclusively Group A Strep (pyogenes)

Question 10

Impetigo pathogens

Answer 10

Group A Strep (pyogenes)

S. aureus becoming more common

Question 11

Impetigo pathogens

Answer 11

Group A Strep (pyogenes) - Contagiosum

S. aureus becoming more common - Bullous

Question 12

Purulent skin infection pathogens

Answer 12

CA-MRSA* - Increasing

MSSA a little bit

Question 13

Necrotizing skin infection pathogens

Answer 13

Polymicrobial (70%)
- Anaerobes, Strep, Enterobacter: surgery, bowel penetration, decubitus ulcer, IVDA, perianal

Monomicrobial (30%)

• S. pyogenes: minor trauma
• Clostridium perfringens (gas gangrene): surgery or major trauma

Question 14

Bite infection pathogens

Answer 14

Cats

• Human: Polymicrobial: Gram + skin flora, oral anaerobes (Eikenella corrodens - need to cover)
• Cat: Pasteurella multocida
• Dog: Pasteurella multocida, capnocytophaga carimorsus

Question 15

DM Foot Infection pathogens

Answer 15

Often polymicrobial

• Gram + early on
• Gram - in chronic infections
• Anaerobes when foul smell
• MRSA if been in hospital recently
• Pseudomonas if patient has been soaking feet

Question 16

Treatment duration Cellulitis

Answer 16

5 days

Longer if delayed clinical response

Question 17

Treatment duration Erysipelas

Answer 17

5 days

Longer if delayed clinical response

Question 18

Treatment duration Impetigo

Answer 18

Usually non-pharm
- soapy wash
Pharm if bad enough
- Topical mupirocin/retapamulin if few lesions
- diclox
- cephalexin
- Augmentin

Question 19

Treatment duration Necrotizing

Answer 19

3-4 days

Question 20

Treatment duration Necrotizing

Answer 20

Until debridement complete + 3-4 days

Question 21

Treatment duration Bites

Answer 21

3-5 days

Question 22

Treatment duration DM Foot Infections

Answer 22

PEDIS 1: ?
PEDIS 2: 10-14
PEDIS 3-4: 21+ days
With associated osteomyelitis: 6-12 WEEKS

Question 23

Treatment duration Osteomyelitis

Answer 23

6-12 weeks depending on surgical situation

Question 24

Cellulitis agents

Answer 24

Mild: dicloxacillin, clinda, Augmentin, cephalexin
Moderate: IV: ceftriaxone, cefazolin, clinda
- systemic signs

Question 25

Cellulitis agents if MRSA suspected

Answer 25

Oral: SMXTMP, clinda, doxy, linezolid IV: vanco, dapto, linezolid, clinda

Question 26

Erysipelas agents

Answer 26

Penicillin - drug of choice | Guidelines recommend same treatment as cellulitis

Question 27

Appearance of Purulent Skin Infections

Answer 27

Pus Furuncles, carbuncles, and abscesses Fluctuant mass

Question 28

Purulent skin infection treatment

Answer 28

``` Mild: IAD Moderate: IAD + ABX - if > 5cm or SIRS - SMX/TMP (unless B-hemolytic suspected) - doxy, clinda, linezolid, vanco/dapto if inpatient ```

Question 29

Necrotizing skin infection treatment

Answer 29

Surgical debridement and possible amputation. Broad spectrum ABX as adjunctive: - Vanco + Pip/tazo - Carbapenem - Cephalosporin + metronidazole - Linezolid + clinda often within first 48-72hrs

Question 30

Bite infection treatment

Answer 30

Surgery if necessary. Augmentin - drug of choice. - Penicillin allergy: Clinda or metro+FQ or SMXTMP Consider prophylaxis right after bite if: - Immunocomprimised - Edema of face

Question 31

DM Foot infection treatment

Answer 31

Imaging and culture down to bone. Treatment setting - PEDIS 1 : outpatient, no ABX - PEDIS 2 : outpatient, toical/oral ABX - PEDIS 3 : out/inpatient, oral or initial IV ABX - PEDIS 4: Initial inpatient, initial IV ABX

Question 32

Classification of Diabetic Ulcer Infections (PEDIS Grade)

Answer 32

``` 1 = not infected 2 = erythema < 2cm 3 = erythema > 2cm 4 = SIRS ```

Question 33

Osteomyelitis pathogens

Answer 33

Hematogenous: S. aureus most commonly Contiguous: Staph, strep, gram -, and anaerobes

Question 34

Osteomyelitis Treatment

Answer 34

``` Surgery right away. ABX once cultures have been collected: IV whole time Empiric therapy only if unstable (vertebral) or culture negative. Children: cover S. aureus - First line: cefazolin, nafcillin Adults: cover S. aureus - First line: cefaczolin, nafcillin - If MRSA risk: vanco, dapto, clinda IV drug users - First line: ceftazidime Contiguous/Diabetic ulcer - same ```