Skin infections and infestations Flashcards
What is an infection
Invasion and multiplication of a disease causing organism which leads to cellular injury
What is the normal skin flora
aerobic cocci:
Staphylococcus epidermis
staphylococcus aureus
Corynebacterium and propionbacterium
yeasts - malassezia furfur
What are the signs of an infection
erythema
hot
tender
pus
exudate
fever
What investigations are done for skin infections
Microscopy, culture and sensitivities
What does a bilateral rash normally eliminate from possible diagnosis
Infection
What is impetigo
Superficial skin infection which does not go deeper than the epidermis
It is the most common bacteria skin infection in children
What are the common pathogens which cause impetigo
Staph aureus is the most common
Strep pyogenes is also common
What is the classical sign that is diagnostic of impetigo
Golden crust
What is the treatment of impetigo
If localised : furisidic acid 3-4 times a day for 5 days
if MRSA give mupirocin
If widespread or severe or bullous -
Oral flucloxacillin 500mg 4x a day
erythromycin oral 500 mg 4x a day
What is the common presentation of cellulitis and erysipelas
Asymmetrical with an acute history
What is the common causative bacteria of cellulitis and erysipelas
erysipelas and cellulitis - strep pyogenes is most common and then staph aureus
What is the treatment for cellulitis and erysipelas
Only if severe:
Flucloxacillin IV 1g every 6 hours
If there is no response add benzylpenicillin iV 1.8g every 6 hours
What is the presentation of necrotising fasciitis
Patient appears very unwell and in pain - when undergoing a CT will see gas bubbles at the infection site
What is the management if bacterial infection of the skin
Take a swab and begin antibiotics since the swab takes time to come back
Adjust the treatment after the swab to what the diagnosed bacteria is vulnerable to and then review in a week
What is the presentation of oedema blisters
Acute exacerbation of oedema
Commonly on dorsum of the feet
often erythematous - red
can feel hot
What is the management of oedema blisters
Drainage of fluid and sending sample for blood test
Doesn’t need antibiotics if systemically well
What is lipodermatosclerosis
Inflammatory issue of the leg which is characterised by subcutaneous fibrosis and skin hardening
Who is lipodermatosclerosis more commonly seen in
Older people with venous issues
What are common signs of lipodermatosclerosis
Signs of venous disease and often bilateral
What is the treatment of lipodermatosclerosis
Treat the underlying venous issue and give topical steroids
Are fungal infections symmetric or asymmetric
asymmetric
What is the treatment for tinea
Tinea on the feet, body, hands or groin respond to topical treatment : Terbinafine or clotrimazole cream
Scalp or nails will respond to oral antifungals
What are the differences between eczema and tinea
Eczema is symmetrical while tinea is asymmetric
Eczema is commonly found on the flexors
What are the common places to get yeast infections
Skin folds
