Infectious Diseases II: SSTI's

Question 1

Mild SSTI classification

Answer 1

systemic signsnot present
NO
Fever
Hr > 90 
WBC > 12000 or < 4000

Question 2

Moderate SSTI classification

Answer 2

Systemic signs present
including: 
Fever
HR > 90
WBC > 12000 or < 4000

Question 3

Severe SSTI classification

Answer 3

failed I&D if purulent + oral antibiotics
Skin sloughing, hypotension, evidence of organ dysfunction
Pt is immunocompromised

Question 4

Impetigo

Answer 4

Superficial SSTI
Caused by strept or staph (MRSA)
Blister-like rash - produce thick yellowish fluid that forms crusts when dry
Common in children

Question 5

Impetigo trreatment

Answer 5

remove dried crust with warm compress
topical mupirocin oint
If numerous lesions, use systemic antibiotic (cephalexin 250 mg QID)

Question 6

Folliculitis/Furuncles/Carbuncles

Answer 6

Mostly caused by s. aureus
Folliculitis: hair follicle infection, looks like red pimple
Furuncles: infection of hair folicle and surrounding tissue (boil)
Carbuncles: group of infected furuncles

Question 7

Folliculitis/Furuncles/Carbuncles treatment

Answer 7

Folliculitis/Furuncles: May only require warm compresss
Carbuncles: incision & drainage 
If systemic signs use oral antibiotic 
Cephalexin 500 mg QID
Treatment failure (then cover for MRSA)
Bactrim 1-2 DS BID
Doxy 100 mg BID

Question 8

Cellulitis

Answer 8

non-purulent infection
Strep (Group A and pyogenes), s. aureus 
Symptoms: 
localized pain
swelling, redness, warmth

Question 9

Cellulitis treatment

Answer 9

Mild symptoms:
Cephalexin 500 mg QID
Clindamycin 300 mg QID (beta lactam allergy)
Others: pen vk, dicloxacillin

Question 10

Cellulitis treatment duration

Answer 10

5 days

greater if no improvement after 5 days

Question 11

Abscess

Answer 11

purulent infection
common caused by CA-MRSA
contagious
consider MRSA nasal decolonization if multiple infections

Question 12

Treatment of mild abscess

Answer 12

no systemic signs

Incision & drainage

Question 13

Treatment of moderate abscess

Answer 13

Systemic signs present 
I&d, culture fluid, antibiotics
Bactrim
Clinda
Doxy
Minocycline
Use cephalexin if culture shows MSSA

Question 14

Severe purulent infections

Answer 14

pts that fail inital treatment
immunocompromised pts
Require IV antibiotics that cover MRSA
streamline antibiotics and switch to PO when appropriate 
Duration: 7-14 days

Question 15

Bite infections don’t require broader antibiotic coverage (t/f)

Answer 15

False
cover for gram -, gram + and anaerobes
use ampicillin/sulbactam, or amox/clav + MRSA coverage

Question 16

Necrotizing fascitis

Answer 16

Strep pyogenes
Group A strep
Fast-moving infection
penetrate to muscle and cause sepsis
intense pain, reddish, purple skin discoloration

Question 17

Necrotizing fascitis empiric treatment

Answer 17

Vanco + beta lactam (Zoysn, meropenem)

Question 18

Common pathogens for diabetic foot infections (DFI)

Answer 18

staph and strep species
can be polymicrobial
E. coli klebsiella, Proteus, pseudomonas
AnaerobicL Bacteroides, peptostreptococcus

Question 19

Monotherapy for DFI

Answer 19

ampicillin/sulbactam
Zosyn
Carbapenems 
Tigecycline (last line)
Moxifloxacin

Question 20

Combo therapy for DFI

Answer 20

Vanco (altn: daptomycin, linezolid)
+
Beta-lactam (zosyn, cefepime, etc.)
maybe add metronidazole if beta lactam does not have anerobic coverage (ceftazidime, cefepime, aztreonam)

Question 21

Duration of therapy for DFI

Answer 21

7-14 days
Severe, deep tissue: 2-4 weeks
Severe, osteomyelitis: 4-6 weeks