Skin/Soft tissue

Question 1

Most common organisms involved in cellulitis

Answer 1

streptococci (mainly Group A) and less frequently S. aureus including methicillin-resistant strains. Community-acquired methicillin resistant staphylococcus aureus (CA-MRSA) should be considered in patients with risk factors or in an area with increasing prevalence of organism.

Question 2

When to consider CA-MRSA in patient with cellulitis

Answer 2

Should be considered in patients with risk factors or in an area with increasing prevalence of organism

Question 3

Main organisms in diabetic foot ulcers

Answer 3

polymicrobial and can involve gram +, gram - and anaerobic bacteria. Often resistant organisms (especially if recurrent infection) may be of concern.

Question 4

best antibiotics for diabetic foot ulcers

Answer 4

broad-spectrum

Question 5

bacteria cause impetigo

Answer 5

strep pyogenes (strep A) and S. aureus

Question 6

oral/topical tx impetigo

Answer 6

Oral
penicillins like dicloxacillin or cephalosporins
MRSA impetigo= clindamycin, sulfa/tri, doxy

Topical
*mupirocin or retapamulin

Question 7

cellulitis vs erysipelas
what part of body usually occur

Answer 7

cellulitis= infection of dermis & SQ tissue
erysepelas= superficial of upper dermis and lymphatics

usually occur in leg

Question 8

ssx systemic inflammatory response syndrome (SIRS) requiring hospitalization for cellulitis

Answer 8

temp > 38 or < 36, RR > 24, HR > 90, WBC >12,000 or < 4,000, altered mental status, hemodynamic instability

Question 9

ABX effective against streptococci in treatment of nonpurulent cellulitis

Answer 9

PCN, amox, amox/clav, dicloxacillin, cephalexin, clindamycin

*monotherapy w/ beta lactam appropriate in uncomplicated cases

Question 10

tx severe cellulitis d/t MRSA

Answer 10

vancomycin (efficacy, safety, low cost)

If MIC > 2 (VRSA)= daptomycin, linezolid, ceftaroline

Question 11

when should abx against MRSA be considered for cellulitis

Answer 11

purulent drainage, abscess, ulcer or penetrating trauma

Question 12

tx carbuncles/furuncles w/ ssx infection

Answer 12

cover S. aureus= dicloxacillin or cephalexin
If suspect MRSA or allergy to PCN= sulfa/tri or doxy

x5-10 days

Question 13

tx carbuncles/furuncles that fail I&D and ABX

Answer 13

vanco, daptomycin, linezolid, ceftaroline (severe cellulitis treatment)

Question 14

risk factors recurrent cellulitis

Answer 14

obesity, edema (use compression stockings), toe abnormalities

Question 15

tx recurrent abscess d/t S. aureus

Answer 15

decolonization regimens:
intranasal mupirocin, chlorhexidine rinses, decontamination towels/sheets

Question 16

main organisms purulent vs nonpurulent

Answer 16

nonpurulent= strep pyogense
purulent= staph aureus including MRSA

Question 17

cellulitis tx previously healthy

Answer 17

dicloxacillin, cephalexin, clindamycin

***suspect MRSA or PCN allergy:
clindamycin, tri/sulfa, doxy, linezolid

Question 18

cellulitis tx comorbidities

Answer 18

amox/clav, levofloxacin, moxifloxacin