IC14 Flashcards
type of SSTI at epidermis
Impetigo
type of SSTI at dermis
Ecthyma & erysipelas
type of SSTI at hair follicles
Furuncles & carbuncles
type of SSTI at subcutaneous fat
Cellulitis
type of SSTI at fascia
Necrotising fasciitis
type of SSTI at muscle
myositis
pathophysiology of SSTIs
Disruption of normal host
defenses -> overgrowth and invasion of the skin and soft tissues by pathogenic microorganisms
non‐pharmacologic interventions for prevention and treatment of diabetic foot infections and pressure ulcers
- Good care to maintain skin integrity, e.g. good wound care;
treatment of tinea pedis;
preventing dry, cracked skin;
Good foot care for DM patients to prevent wound and ulcers; - Predisposing factors should be identified and treated
prevention of SSTIs in acute traumatic wound
Acute traumatic wounds should be copiously irrigated, foreign objects removed, and devitalized tissues debrided
When is a cultured needed for SSTIs?
Wound with pus, exudates or tissues
How should culture sample be obtained from wound?
culture should be collected
- from deep in the wound after surface cleansed
- from base of a closed abscess, where bacteria grow
- by curettage, rather than wound swab or irrigation
When is a blood culture warranted?
Severe cases with marked systemic symptoms of infection or immunocompromised patients
Is Erysipelas well-demarcated?
Yes
Where is Erysipelas commonly found?
Face, lower extremities
Where is cellulitis commonly found?
lower extremities, although it can appear on any area of the skin
Likely pathogens for Impetigo
Staphylococci or streptococci
Bullous form of impetigo is caused by _____
toxin‐producing strains of S. aureus
Likely pathogens for Ecthyma
Most frequently caused by group A streptococci
Likely pathogens for Nonpurulent (cellulitis, erysipelas)
Mainly beta‐hemolytic streptococcus;
Usually group A strep (Strep. Pyogenes)
Likely pathogens for purulent (furuncles, carbuncles, skin abscesses, cellulitis)
Caused mainly by S. aureus;
Some beta‐hemolytic streptococcus;
Isolation of multiple organisms (including gram‐negatives and anaerobes) is more common in patients with skin abscess
Which SCCmec strain causes CA-MRSA? (more common in US)
SCCmec IV
Treatment for CA-MRSA
Oral non‐beta‐lactams (eg clindamycin, co‐trimoxazole, doxycycline)
Treatment for impetigo, mild limited lesions
Topical Mupirocin BID x 5 days
Pathophysiology for DFIs
Neuropathy + Vasculopathy + Immunopathy -> Ulcer formation or wounds -> Bacterial colonization, penetration, proliferation -> DFIs
Likely pathogens for DFIs/ pressure ulcer
Typically polymicrobial:
Staphylococcus aureus and Streptococcus spp. most common;
Gram‐negative bacilli (E. coli, Klebsiella spp., Proteus spp) / Pseudomonas less common unless there is water exposure;
Anaerobes (Particularly in ischemic or necrotic wounds)
SIRS criteria
temperature > 38 or < 36, heart rate > 90 bpm, respiratory rate > 24 bpm, WBC > 12 x 109/L or < 4 x 109/L
Criteria for infection in DFI and pressure ulcers
Purulent discharge or at least 2 signs of inflammation (erythema, pain, induration, warmth, tenderness)
