SSTI/OSTEO

Question 1

Abscess Bugs

Answer 1

-S. aureus (and MRSA)
-Gram - bacilli

Question 2

Cellulitis Bugs

Answer 2

-Purulent: S. aureus, MRSA

-Non-purulent: Streptococci pyogenes

Question 3

Surgical Sites Bugs

Answer 3

-S. aureus (MRSA)
-Enterococcus spp
-E. coli
-Staph coag neg

Question 4

IDSA Guidelines, Diagnosis

Answer 4

Moderate
-SSTI with systemic signs/sx

Severe
-Purulent: > 38 fever, HR > 90, RR > 24, WBC > 12, immunocomp
-Non: same ^ plus failed oral therapy or skin sloughing

Question 5

Impetigo/Ecthyma Bugs

Answer 5

Bullous Impetigo
-Staph aureus (MRSA/MSSA)

Non-bullous Impetigo
-Staph aureus
-Strep pyogenes

Ecthyma
-Staph aureus
-Strep pyogenes

Question 6

Impetigo/Ecthyma TX

Answer 6

*Empiric tx should cover both MSSA and streptococci

-Dicloxacillin
-Cephalexin
-Clindamycin (pcn allergy)
-Doxycycline (pcn allergy)
-Sulf/TMX (pcn allergy)

DCDCS

Question 7

Furuncles/Carbuncles TX

Answer 7

-S. aureus

Large: incision, drainage

Systemic abx not needed unless systemic sx

Chlorhexidine soap (hibiclens)

Question 8

Cutaneous Abscess TX

Answer 8

Polymicrobial
-S. aureus (MRSA)

Incision and drainage

Culture to see if systemic abx are needed

Question 9

Cellulitis TX

Answer 9

-Penicillin (if strep susceptible)
-Cephalexin (strep/mssa)
-Clinda (strep/mssa/mrsa)
-Cefazolin (strep/mssa)
-Dicloxacillin (strep/mssa)
-Amox/Clav (strep/mssa)

CCC PDA

TX is 5-10 days

Question 10

Necrotizing Fasciitis Bugs

Answer 10

Polymicrobial
-Aerobic + anaerobi

Monmicrobial
-S. pyogenes (most common)
-S. aureus
-Clos. spp.
-Vibrio vuln
-Aeromonas hydro

Question 11

Necrotizing Fasciitis TX

Answer 11

Empiric tx should be broad

-MRSA coverage
= Vanco, dapto, linezolid

-Gram neg, anaerobic coverage
= pip/tazo, carb, cetriaxone with metronidazole

-Add clindamycin

Question 12

Fournier Gangrene Bugs

Answer 12

-S. aureus
-P. aeruginosa
-E.coli, Klebisiella
-Anaerobes

Question 13

Pyomyositis TX

Answer 13

Infection within a muscle

BROAD empiric tx
-MRSA, Gram -, anaerobe
= Vanco, dapto, linezolid
= pip/tazo, carb, cetriaxone with metronidazole

S. aureus, S. pyogenes, S. pneumonia, Gram -

Question 14

Bite Wounds TX

Answer 14

For P. mult, Eikenella
-Amox/Clav
-Doxycycline

P. mult only
-Levofloxacin

P. mult, anaerobes
-Moxifloxacin

CEFAZOLIN/CEPHALEXIN DO NOT COVER PASTEURELLA

Question 15

Purulent MRSA/MSSA vs Non beta-hemolytic strep

Answer 15

Purulent MRSA/MSSA
= doxy, clinda, bactrim

Non
= cephalexin, clinda

Question 16

Diabetic Foot Infections Bugs

Answer 16

-MSSA/MRSA
-Gram neg bacilli (P. aeru rarely)
-Anaerobes

Most common are Staphylococcus aureus and Streptococcus spp.

Question 17

MILD DFI TX

Answer 17

Oral agents
-Clindamycin
-Cephalexin
-Levofloxacin
-Amoxicillin-clavulanate
-Doxycycline
-Trimethoprim-sulfamethoxazole

Question 18

MODERATE DFI TX

Answer 18

Broader, covering Gram neg

Oral or IV
-Levofloxacin
-Moxifloxacin
-Clindamycin + ciprofloxacin
-Ceftriaxone
-Cefoxitin
-Ampicillin-sulbactam

MRSA coverage based on risk factors

Question 19

SEVERE DFI TX

Answer 19

-Ertapenem
-Imipenem-cilastatin
-Meropenem
-Pip/tazo
-Ceftazidime
-Aztreonam
-Cefepime
-Vancomycin
-Daptomycin
-Linezolid

EXAMPLE
-VDL + cefepime/ceftazidime/aztreonam + metro

*pip/tazo avoid with Vanco = AKI
*ertapenem for P. aeru RF

Question 20

RF for P. aeru in DFI

Answer 20

-High local prevalence of P. aeruginosa infections
-Infection occurs in a warm climate
-Frequent exposure of infected foot to water
-PRIOR ANTIBIOTIC EXPOSURE

Question 21

DFI Duration of TX

Answer 21

1-4 weeks

Mild 1-2
Mod 1-3
Sev 2-4

Question 22

Osteomyelitis Bugs/Duration

Answer 22

S. aureus (MSSA/MRA)
S. epidermidis
E. coli
K. pneumonia
Proteus spp
P. aeruginosa

Acute: 6 wks parenteral

Chronic: 4-6 weeks antibiotics (po vs iv)

CRP > 3.2
ESR > 60

Question 23

Ceftaroline

Answer 23

AE: myelosuppression

Covers strep, staph (MRSA), entero

Question 24

Tedizolid

Answer 24

Covers strep, staph (MRSA), entero (VRE)

200 mg, no adjustments

Question 25

Oritavancin

Answer 25

Gram-positive pathogens (including MRSA)

1200 mg IV once

No renal adj over > 30

Question 26

Dalbavancin

Answer 26

Gram-positive pathogens (including MRSA)

1 g then 500 mg