Infections And Infestations Of The Skin Flashcards
What are the four types of skin infections and infestations?
Common bacterial infections
Viral infections
Fungal infections
Parasites infestations
What bacterial infections can be cause by Staph. Aureus?
Impetigo
Folliculitis: Furunculosis, Carbuncles
Cellulitis
Ecthyma
Staphylococcal scalded skin syndrome (SSSS)
Superinfects other dermatoses (e.g. atopic eczema, HSV, leg ulcers)
What bacterial infections are caused by streptococcus pyogenes?
Impetigo
Cellulitis
Ecthyma
Erysipelas
Scarlet fever
Necrotizing fasciitis
Superinfects other dermatoses (e.g. leg ulcers)
What is folliculitis?
Follicular erythema, sometimes pustular
What are the two types of folliculitis?
May be infectious or non-infectious
What are the treatment options for folliculitis?
Antibiotics - flucloxacillin and erythromycin
Incision and drainage is required for furunculosis
What is the difference between a furuncle and a carbuncle?
A furuncle is a deep follicular abscess involving one follicle
A carbuncle is a deep follicular abscess involving several adjacent follicles
Carbuncle - more likely to lead to complications such as cellulitis and septicaemia
What is cellulitis?
Infection of lower dermis and subcutaneous tissue
Tender swelling with ill-defined blanching erythema or oedema
In most cases what is the cause of cellulitis?
Strep. Pyogenes or staph. Aureus
What is a predisposing factor for cellulitis?
Oedema
what is the treatment given for cellulitis?
Systemic antibiotics
What is impetigo?
Superficial bacterial infection, stuck-on, honey-coloured crusts overlying an erosion
What is impetigo caused by? Non-bullous vs bullous
Non-bullous = streptococci
Bullous = staphylococci
Where does impetigo often affect?
Perioral, ears, nares
What is impetigo treated with?
Topical and systemic antibiotics
What is impetiginisation?
Impetiginisation: occurs in atopic dermatitis -> superimposed infection -> gold crusting
What is ecthyma?
Severe form of streptococcal impetigo
Thick crust overlying a punch out ulceration surrounded by erythema
Usually on lower extremities
What is erysipelas?
Infection of deep dermis and subcutis
What causes erysipelas?
beta-haemolytic streptococci or staph. Aureus
what does erysipelas present as?
Presents as erythematous indurated plaque with a sharply demarcated border and a cliff-drop edge (+/- blistering)
What are the signs and symptoms associated with erysipelas?
Painful
Face or limb (+/- red streak of lymphangitis and local lymphadenopathy)
Portal of entry must be sought (e.g. tinea pedis).
Prodrome of malaise, fever, headache.
What treatment is given for erysipelas?
IV antibiotics
What is staphylococcal scalded skin syndrome?
Clinically resembles Stevens-Johnsons, due to exfoliative toxin that kidneys cannot excrete quickly enough
Diffuse tender erythema progresses to flaccid Bullae, then wrinkle and exfoliate leaving oozing erythematous base
