Skin infections Flashcards
(59 cards)
What is cellulitis?
Bacterial infection of the skin
What is the most common causative organism of cellulitis?
Strep. pyogenes
What can predispose people to cellulitis?
Oedema/poor circulation in the legs
How does cellulitis typically present?
- infected area is red, hot & swollen
- pyrexia
- general malaise
Investigations for cellulitis?
Bacterial swab
Management of cellulitis?
Flucloxacillin 1st line
Doxycycline if pen allergic
Vancomycin if MRSA
What is necrotising faciitis?
Life threatening soft tissue infection, basically a deeper and more serious cellulitis
Explain the pathophysiology of necrotising faciitis?
extensive tissue necrosis and toxaemia
What is the most common causative organism of necrotising faciitis?
Strep. pyogenes - around wounds/post-surgery
How does necrotising faciitis typically present?
- out of proportion pain (excruciating pain under a wound that doesn’t look that impressive)
- crepitations when skin is felt (air in skin)
- signs of infection: fever, tachycardia, hypotension
How is necrotising faciitis treated?
Immediate surgical debridement and antibiotics
What is impetigo?
V contagious superficial bacterial infection that usually affects the face in children
What is the most common cause of impetigo?
Staph aureus
How does impetigo typically present?
Red lesions with a yellow/gold crust, usually on the face
Management of impetigo?
1st line = topical fusidic acid 7 days
extensive/severe = oral flucloxacillin
What is staphylococcal scalded skin syndrome?
Blistering condition due to toxins released by certain strains of staph aureus, usually in children under 5
Explain the pathophysiology of staphylococcal scalded skin syndrome?
- Toxins from certain strains of staph aureus bind to desmosomes in the skin and break them up so that keratinocytes become unstuck
- This splits the epidermis at the granular layer and creates blisters
How does staphylococcal scalded skin syndrome typically present?
- red, blistering skin (looks like burns)
- tender & painful
- superficial epidermis peels off in sheets
Management of staphylococcal scalded skin syndrome?
IV flucloxacillin
Supportive treatment - fluid & electrolyte balance & pain relief
What is ringworm?
A fungal (dermatophyte) infection of the skin
What is the most common causative organism for ringworm and what type of transmission is it passed on by?
Trichophyton rubrum
Human-human transmission
What are the 2nd and 3rd most common causative organisms for ringworm and what type of transmission are they passed on by?
2nd = trichophyton mentagraphytes (human-human) 3rd = microsporum canis (cats/dogs-human)
What is tinea capitis?
Ringworm in the scalp
What is tinea barbae?
Ringworm in the beard