Skin and Soft Tissue

Question 1

SSTI’s are divided into….

Answer 1

purulent and non-purulent

Question 2

Purulent

Answer 2

• (pus)

Bullous impetigo, carbuncles, cutaneous abscess, folliculitis, purulent cellulitis

Question 3

Non-purulent

Answer 3

non-bullous impetigo, non-purulent cellulitis

Question 4

Cellulitis affects….

Answer 4

epidermis and dermis; may spread within superficial fascia

Question 5

How can cellulitis spread?

Answer 5

May spread through lymphatic tissue and bloodstream –> complications (spread through blood to other tissue)

Question 6

Symptoms of Cellulitis

Answer 6

• Affected area hot and painful; erythema and edema of skin
• Fever, chills, malaise
• Often history of antecedent minor trauma, abrasion, ulcer or surgery
  Affected area generally warm to the touch
  -Inflammation with little or no necrosis or suppuration of soft tissue
  -May be associated with purulent drainage, exudates and/or abscess
• Tender lymphadenopathy
  Hypotension, dehydration, altered mental status

Question 7

What organisms are responsible for cellulitis?

Answer 7

Group A Streptococcus – GAS
Staphylococcus aureus

Question 8

Organism of Non-purulent

Answer 8

• Streptococcus pyogenes

Question 9

Organism of purulent

Answer 9

• Staphylcoccus auereus

Question 10

Non-purulent 1st Line Choice

Answer 10

Cephalexin (1st Gen Cephalosporin)
500 mg po QID ( adult)
50 – 100mg/kg/day divided QID (pediatric)

Question 11

Penicillin Allergy Options

Answer 11

• Clindamycin
• Erythromycin

Question 12

Clindamycin Dose Pen. Allergy

Adult and Pediatric

Answer 12

300mg po QID or 450 mg po TID (adults)

20-40mg/kg/day po divided TID or QID(pediatric)

Question 13

Erythromycin Dose Pen Allergy

Adult and Pediatric

Answer 13

250 mg po QID or 500mg po BID (adult)

30-40mg/kg/day po divided BID (pediatric)

Question 14

Purulent Cellulitis (MMSA)

Answer 14

Cephalexin (1st Gen Cephalosporin)
500 mg po QID ( adult)
50 – 100mg/kg/day divided QID (pediatric)

Cloxacillin 500 mg po QID (adult)
50 mg/kg/day po divided QID (pediatric)

Question 15

Purulent Cellulitis - MMSA or True Penicillin Allergy

Answer 15

TMP/SMX – DOC
1 -2 DS tab po BID (adult)
8-12 mg/kg/day (TMP) po BID

Doxycycline
100 mg po BID (adult)
4 mg/kg/day po BID (children 9 or older)

Question 16

Empiric Therapy for GAS and MRSA

Answer 16

Cephalexin plus TMP/SMX
OR cephalexin plus doxycycline

Requires two antibiotics because cephalexin covers GAS but not MRSA

Question 17

Duration of Therapy of Cellulitis

Answer 17

5 days of therapy is as effective as 10 days providing there is clinical improvement by day 5

May worsen in first few days (after incision and drainage + antibiotics); this is part of the healing process and NOT tx failure

Question 18

When will full skin heal?

Answer 18

Full skin healing (inflammation and symptoms) may take 1 -2 weeks after antibiotics are stopped

Question 19

Non-pharmocolgic Tx

Answer 19

Incision and Drainage – I & D
Key to successful treatment of purulent skin infections
For abscess < 5 cm I&D alone is adequate; antibiotics do not help heal the infection any faster

Elevation of affected limb
- often essential for successful cellulitis therapy