Skin and Soft Tissue Infection Flashcards
1
Q
Cellulitis
- Define
- Define Erysipelas
- Define Cellulitis
A
- Inflammation of the skin and subcutaneous tissues
- upper dermis and superficial lymphatics
- involves deeper dermis and subcutaneous fat
2
Q
Cellulitis Presentation
- Signs/Symptoms (4)
- Predisposing factors (5)
- Common Sites (3)
A
- Varies: Erythema, swelling, tenderness, warmth, fevers/chills (systemic symptoms), lymphangitis, edema, induration (hardening); may have a sharp demarcation
- Break in skin
Edema
skin conditions
immunosuppression
procedures - Lower extremities
Face
Places of skin breakdown
3
Q
Common Bugs of Cellulitis
- Gram +
- Human bites (gram -)
- Cat bites (gram -)
- Dog Bites (gram -)
A
- Gram +: Group A Strep, other hemolytic Strep, S. aureus (MRSA and MSSA)
- Eikenella corrodens
- Pasteurella multocida
- Capnocytophaga canimorsus
4
Q
Gram stain appearance of
- Strep
- Staph
A
- Gram + cocci in chains
2. Gram + cocci in clusters
5
Q
Differential Diagnosis for Cellulitis (3 main groups)
A
- vascular disorders (thrombophlebitis, lymphedema)
- Dermatologic disorders (contact dermatitis, drug rxns, insect stings/bites, urticaria)
- Immunologic (gouty arthritis, Lupus, sarcoid)
6
Q
- Define Purulent Cellulitis
- Define Non-purulent Cellulitis
- What causes purulent?
- What causes non-purulent?
A
- cellulitis associated with purulent drainage (abscess) or exudate in abscence of drainable abscess
- cellulitis with no purulent drainage, exudate, or abscess
- Staph (MRSA)
- Strep species and Staph (MSSA)
7
Q
- Where does purulent material drain from an abscess?
2. What does abscess feel like?
A
- central area
2. fluctuant, moves
8
Q
Purulent Cellulitis
- Abscess management
- No drainable abscess
A
- incise and drain w/ gram stain and culture;
Need to give antibiotics - still need to cover CA-MRSA
9
Q
Non-Purulent Cellulitis
- What do you need to cover w/ Abx?
- Specific Abx for MSSA and Strep
- Specific Abx for CA-MRSA and Strep
A
- cover Strep and staph species (MRSA coverage not necessary)
- Beta-lactam (cephalexin, dicloxacillin)
- Clinda, Linezolid, bactrim, or doxy + beta-lactam
10
Q
How should joint infections be treated?
A
Aggressively; can have long lasting damage
11
Q
Complications of Cellulitis (3)
A
- Sepsis
- Toxic Shock Syndrome (both Staph and Strep can cause)
- Necrotizing Fasciitis
12
Q
Risk Factors of Staph Toxic Shock Syndrome (9)
A
Menses, women, wound infections, mastitis, sinusitis, osteo, burns, lesions, arthritis
13
Q
Staph Toxic Shock Syndrome Presentation
- Systemic manifestations
- Blood Cultures
- Skin Manifestations (2)
- Multi-organ involvement
A
- fever, hypotension
- usually negative
- diffuse fine macular erythema; desquamation (often of palms/soles)
- N/V; diarrhea; thrombocytopenia, delirium, transaminitis; mucosal hemorrhage/hyperemia
14
Q
Staph TSS
- What causes disease
- Medical Management
- Surgical Management
A
- TSS toxin-1 (TSST-1) acting as a super Ag which activates a large number of T cells –> massive cytokine production and release
- Supportive: fluids, vasopressor support; Abx
- removal of any foreign body
15
Q
Strep TSS
- Risk Factors
- Pathogenesis
A
- Surgery, injuries, trauma
2. Group A Strep creates exotoxins that act as superantigens (pyrogenis exotoxin A and B: SPEA and SPEB)