SSTI

Question 1

What is the outermost layer of the skin?

Answer 1

Epidermis

Question 2

What are the two innate immune system cells present in the outermost layer of the skin?

Answer 2

Keratinocytes and Langerhans’ cells

Question 3

3 main organisms on the skin

Answer 3

.Staphylococcus species
.Corynebacterium species
.Propionibacterium species

Question 4

The skin is mostly colonized by gram (positive/negative) bacteria

Answer 4

Positive

Question 5

What is dysbiosis?

Answer 5

An imbalance in a microbial community. Overgrowth of certain organisms

Question 6

Which of the following is not a common colonizer of the skin?
a. Streptococcus mitis
b. Pseudomonas aeruginosa
c. Staphylococcus epidermidis
d. Candida albicans

Answer 6

b. Pseudomonas aeruginosa

Question 7

(Purulent/nonpurulent) SSTIs require incision and drainage (I and D)

Answer 7

Purulent

Question 8

Impetigo is commonly associated with which organism?

Answer 8

Group A streptococcus (pyogenes)

Question 9

True or false: Impetigo penetrates dermis &
infects keratinocytes

Answer 9

False. Impetigo penetrates epidermis &
infects keratinocytes

Question 10

Duration of treatment for impetigo

Answer 10

.5-7 days
.Mild: 5 days
.Extensive: 7 days

Question 11

A 65yo M presents with complaints on LLE pain, swelling,
redness after scraping his leg on an end table in his home.
* Vitals: HR 90, RR 22, BP 156/98, Tmax 99.1 F
* Physical exam: no open lesions identified, there is clear
demarcation of the erythema, no purulence or pain out of
proportion identified
* Allergies: NKDA PMH: HTN, HLD, obesity
23

Which of the following SSTIs does this patient likely have?
a. Impetigo
b. Ecthyma
c. Cellulitis
d. One we haven’t discussed yet

Answer 11

c. Cellulitis

Question 12

A 65yo M presents with complaints on LLE pain, swelling,
redness after scraping his leg on an end table in his home.
* Vitals: HR 90, RR 22, BP 156/98, Tmax 99.1 F
* Physical exam: no open lesions identified, there is clear
demarcation of the erythema, no purulence or pain out of
proportion identified
* Allergies: NKDA PMH: HTN, HLD, obesity
23

Which of the following is the most appropriate to treat this
patient?
a. Cephalexin 250-500mg PO Q6H
b. Vancomycin 15mg/kg Q12H IV
c. Clindamycin 300mg Q6H PO
d. Topical mupirocin applied to the affected areas BID

Answer 12

a. Cephalexin 250-500mg PO Q6H
Mild, can use PO

Question 13

A 65yo M presents with complaints on LLE pain, swelling,
redness after scraping his leg on an end table in his home.
* Vitals: HR 90, RR 22, BP 156/98, Tmax 99.1 F
* Physical exam: no open lesions identified, there is clear
demarcation of the erythema, no purulence or pain out of
proportion identified
* Allergies: NKDA PMH: HTN, HLD, obesity
23

What is the most appropriate duration of therapy for this
patient?
a. 3 days
b. 5 days
c. 7 days
d. 14 days

Answer 13

b. 5 days
Mild therapy is 5 days

Question 14

Folliculitis is (purulent/nonpurulent) and occurs at the _______ ________

Answer 14

Purulent. Hair follicle.

Question 15

Treatment for non-severe and severe folliculitis

Answer 15

Non-severe: Mupirocin or retapamulin topical BID
Severe: Cefepime, zosyn, meropenem

Question 16

Furuncle and carbuncle treatment duration of treatment

Answer 16

7-14 days from I and D (7 days for milder disease)

Question 17

A 25yo F presents with a large pustule under her arm that is
inflamed and indurated. She has been living with the pain for
the past week but she began to feel feverish so she presents to
the ER
* Vitals: HR 99, RR 24, BP 102/68, Tmax 102.7 F
* Physical exam: appears to be a collection of underarm lesions
with frank pus
* Allergies: sulfa drugs PMH: none
* Blood cultures: negative

Which of the following treatment plans is most appropriate for
this patient?
a. I&D followed by piperacillin-tazobactam 3.375g IV Q6H
b. I&D followed by cefepime 1g IV Q8H
c. I&D followed by vancomycin 15mg/kg IV Q12H targeting an
AUC of 400-600
d. I&D followed by SMX/TMP 1 DS tablet PO Q12H

Answer 17

c. I&D followed by vancomycin 15mg/kg IV Q12H targeting an
AUC of 400-600