Bacterial Skin Infections - JD Flashcards
Folliculitis
Papular or pustular inflammation of hair follicles with purulent material in the epidermis
Furuncle
Painful, firm or fluctuant abscess originating from a hair follicle “boil” purulent material extends through dermis to Sub-Q tissue
Carbuncle
A network of furuncles connected by sinus tracts. Purulent drainage
Cellulitis
Painful, erythematous infection of dermis and Sub-Q with poorly demarcated borders
Erysipelas
Fiery red, painful infection of superficial skin (dermis) with sharply demarcated borders
Impetigo
Large vesicles and/or honey-crusted sores, contagious, superficial bacterial skin infection
Impetigo is common in what population?
common in infants & children (2-5 y.o.)
What are the differences between Non-bullous impetigo and Bullous impetigo?
1) Non-Bullous: pustule rupture exposes red, moist base. Honey-yellow to white-brown adherent crust forms
- Heals without scarring
- Staph/Strep
- Children/Adults
2) Bullous: Flaccid bullae filled with clear yellow fluid turns to turbid and brown. Rupture bullae leave thin brown crust.
- Common on trunk
- Always S. aureus
- Scarring is possible
- Infants/preschool
What is the Tx for a patient with impetigo?
- Usually self-limiting so treat symptoms
- Wash with anti-bacterial soap to remove crust
- Bactroban BID x 5-7 days
- PO Abx → Cephalexin
- if MRSA → Doxy, Bactrim
- Limit exposure to others
Note: May have post-strep glomerulonephritis
What is the difference in the level of infection between Erysipelas and Cellulitis?
Erysipelas → epidermis & dermis
Cellulitis → dermis & subcutaneous tissue
What are the causative agents of Erysipelas and Cellulitis infections?
- GABHS (S. pyogenes)
- S. Aureus
- MRSA
- Other G (-) aerobes and fungi (rarely)
What are S/S of Erysipelas & Cellulitis?
- Red, hot, swollen, tender, edema
- swollen or tender lymph nodes
- chills and fevers
- Erysipelas: superficial lymphatic involvement
- Cellulitis: slower course present with or without purulent drainage/exudate
What are treatment options for Erysipelas/Cellulitis?
Erysipelas: PCN
Cellulitis: Pen V, augmentin
MRSA: Clinda/Doxy/Bactrim
-Mild (PO) → Severe (IV)
What is a potential pitfall of cellulitis Tx?
Necrosis: weakened tissue will not be perfused → no Abx will get to site
If no improvement → consider surgical debridement
Facial Cellulitis → vision loss
Necrotizing Fasciitis → flesh eating bacteria
What organism is associated with cat/dog bites, and how is it treated?
- Pasteurella multocida
- Tx: Augmentin 875 mg BID x 10 days
What is the treatment for a patient with Bartonella Hens (cat scratch disease)?
-Macrolide (azythro) or Doxy
What vaccines should you consider giving to a patient who has suffered a dog bite?
Tetanus and Rabies vaccines
What are the characteristics of a Folliculitis skin lesion and what are the common pathogens causing it?
- Superficial infection of hair follicle with purulent material in epidermis.
- Begins as thin, yellowish-white pustules with a hair coming out the middle
- Pathogens: Staph & Pseudomonas Aeruginosa
What medication may precipitate folliculitis?
Corticosteroids (steroid acne)
What are treatment options for Folliculitis?
- Good skin hygiene
- Topical Abx (Bactroban)
- If deeper infx → cephalexin or dicloxacillin
What do furuncles and carbuncles evolve from?
Staphylococcal folliculitis
Hidradenitis Suppurativa is a recurring abscess of what gland?
-Apocrine gland (axilla, perianal, groin, perineum)
What are the clinical manifestations of Staphylococcal Scalded Skin Syndrome (SSSS)
- Blisters, fever, desquamation, pain, erythema
- Diffused sheetlike desquamation
- Positive Nikolsky’s sign (slight rubbing of skin results in exfoliation and wet appearance of skin)
What is the Tx for SSSS?
Oxacillin or nafcillin
Possibly Vancomycin if MRSA suspected
What is the Tx for decolonization of nasal MRSA?
Intranasal topical Mupirocin (Bactroban) BID x 5 days & Chlorhexidine baths 5-14 days
