IC14: SSTI Flashcards
Suggest Non-pharm measures for DFI
1) Wound care
o Debridement
o “Off‐loading” = relieving pressure on ulcer
o Apply dressings that promote a healing environment and control excess exudation
2) Foot care
o Daily inspection (check for cracks, dryness or wounds beginning to occur, remember to check bottom of foot as well)
o Prevent wounds and ulcers (don’t go barefoot even at home at least wear socks, avoid footwear that is too tight or too loose)
o Nail and foot care hygiene
* Wash feet with soap every day including between toes, dry feet properly
* Moisturise but don’t moisturise in between toes (could lead to fungal infections)
* Nail care: try to prevent ingrown toenails so don’t cut too thinly (leave a bit of gap) + cut straight across the nail rather than usual round/circular manner.
3) Optimal glycemic control and management of risk factors (e.g stop smoking)
Suggest Non-pharm measures for pressure ulcers
1) Debridement of infected or necrotic tissue
2) Local wound care
o Normal saline preferred
o Avoid harsh chemicals
3) Relief of pressure
o Turn or reposition every 2 hours
o Use different kind of mattresses that prevent pressure ulcers
o Also important for prevention
What are the risk factors for SSTI? (3 broad ones)
1) Disruption of the skin barrier
o Traumatic:
e.g Lacerations, recent surgery, burns, abrasions, crush injuries, open fractures, injection drug use (illicit drug), human and animal bites, insect bites
o Nontraumatic:
e.g Ulcers, tinea pedis (bacteria can enter through breaks in skin), dermatitis, toe web intertrigo, chemical irritants (disrupt chemical balance)
o Impaired venous and lymphatic drainage
e.g Saphenous venectomy, Obesity, Chronic venous insufficiency
o Peripheral artery disease
2) Conditions that predispose to infection
e.g Diabetes, Cirrhosis, Neutropenia, HIV, Transplantation and immunosuppressive medications
3) History of cellulitis
What is the clinical presentation of impetigo/ecthyma?
Impetigo: Erythematous papules that rapidly evolve into vesicles and pustules that rupture, with the dried discharge forming honey‐coloured crusts on an erythematous base. Lesions well localised, frequently many, bullous or non-bullous in appearance.
Ecthyma: ulcerative form of impetigo. Lesions extend deep into dermis from epidermis
Itching is common for both. Usually occur on exposed areas of the body e.g face and extremities
What is the clinical presentation of furuncle, carbuncle and skin abscesses?
Furuncle: An infection of the hair follicle in which purulent material extends through the dermis into the subcutaneous tissue, where a small abscess forms.
Carbuncle: Formed when furuncles coalesce and extend into subcutaneous tissues
Skin abscess: Collections of pus within the dermis and deeper skin tissues. Skin abscesses manifest as painful, tender, fluctuant and erythematous nodules
Furuncles progress to Carbuncle which progress to Skin abscess if left untreated.
What is the clinical presentation of cellulitis vs Erysipelas?
Erysipelas: affects upper dermis; Fiery red, tender, painful plaque (raised above surrounding skin) with well‐demarcated edges. Common on face, also lower extremities.
Cellulitis: Involves deeper and subcutaneous fats. Usually presents as an acute, diffuse, spreading, non-elevated, poorly demarcated area of erythema. Relatively rapid onset/progression. Almost always unilateral. Fever in 20–70% of patients. It is typically found on the lower extremities, although it can appear on any area of the skin. Might be poorly demarcated due to it being deeper infection.
TLDR;
1) Erysipelas are well demarcated, Cellulitis is not
2) Cellulitis affects deeper layers (subQ) vs upper dermis for erysipela
What is the pathogen usually implicated in purulent SSTIs?
S. Aureus
What is the pathogen usually implicated in non-purulent SSTIs?
Group A Strep (S. Pyogenes)
When would multiple organisms most likely be isolated from a properly obtained wound culture?
1) Skin abscess involving the perioral, perirectal or vulvovaginal areas
2) DFI
3) Pressure ulcer
Water exposure increases risk of infection of which organisms?
Aeromonas (freshwater exposure), Vibrio vulnificus (seawater exposure), Pseudomonas (“hot tub cellulitis”)
What are the most likely pathogens in Impetigo?
Staphylococci or Streptococci
Bullous form caused by toxin-producing strains of S. Aureus
What is the common pathogen in Ecthyma?
Group A Strep
State the empiric treatment for mild Impetigo.
TOP Mupirocin BID for 5 days
State both empiric and culture directed treatment for Impetigo/ Ecthyma
Empiric:
PO Cephalexin or Cloxacillin
PO Clindamycin (penicillin allergy)
Culture directed (MSSA): Cloxacillin or Cephalexin
Culture directed (GAS): Pen V or Amoxicillin
Duration: 7 days
What is the gold standard for treatment of purulent SSTIs?
Incision and drainage
When will systemic antibiotics be used for purulent SSTIs? (6)
1) Unable to drain completely
2) Lack of response to I&D
3) Extensive disease involving several sites
4) Extremes of age (immunocompromised)
5) Immunosuppressed (e.g. chemotherapy, transplant)
6) 2 or more signs of systemic illness:
- HR> 90,
- temperature > 38deg or < 36deg,
- RR > 24,
- high or low WBC
