4. Dermatology A Flashcards
(33 cards)
Main function of skin
- Barrier and protection - epidermis
- Strength and flexibility - dermis
- Fat and insulation - SC tissue
What is found in epidermis?
Stratum corneum is outside layer which is thickest on palms and soles of feet
Langerhan cells are found here - immune function
What is found in the dermis?
- Made of collagen, elastin and fibrillin
- Nerves
- Glands
- Hair follicles
- Blood vessels
Outline psoriasis from epidermis
Increased cell turnover
Hyperproliferation/thickening of epidermis
Causes scaly plaques
Dilation of BV causes erythema
What diseases affects flexural areas?
Eczema
What can affect mucus membranes?
Lichen planus with lace-like reticular pattern
What is the first line treatment for mild/moderate acne?
Topical benzoyl peroxide + topical adapalene
Topical benzoyl peroxide + topical clindamycin
Topical tretinoin + topical clindamycin
What is the treatment for moderate/severe acne?
Either of first 2 options from mild/moderate OR
Topical adapalene + topical benzoyl peroxide + oral doxycycline/oral lymecycline
Topical azelaic acid + oral doxycycline/oral lymecycline
Can use COCP instead of oral abx
Isotretinoin is reserved for secondary care
What is SCC?
- Common variant skin cancer
- Arises from squamous cells -flat, thin cells found in dermis
- Rapidly expanding, ulcerated nodules
- Some bleed
What are the risk factors of developing a squamous cell carcinoma?
Sun exposure
Tanning beds
Immunosupression
Genetic conditions eg Xeroderma pigmentosum
How is SCC managed?
- Surgical excision with 4mm margin (6mm in high risk lesions)
- Mohs micrographic surgery - tissue removed and examined under microscope in real time to ensure all cancerous cells are removed
- Radiotherapy
- Curretage and cautery
- Topical 5-fluorouracil or imiquimod
- Cryotherapy
When is cryotherapy used for a SCC?
If there is a low risk of it being cancerous e.g. flat and superficial
Safety netting for SCC
- If increasing in size rapidly and invading surrounding structures
- Lumps in neck
What is BCC?
- Most common type of non-melanoma skin cancer worldwide
- Exposure to UV light
- More risk if fairer and easily burn
- Can vary greatly in appearance
- Curable in most cases
- Rarely spread
Management for BCC?
- Wide local excision
- Cryotherapy
- Iquimoid cream
- Curretage
- Mohs micrographic surgery
- Radiotherapy
Safety netting for BCC
- 50% of people will develop 2nd BCC within 3yrs of first
- Prevent further lesions by preventing sunburn
- At increased risk of other cancers eg melanomas
- Do regular self skin checks and annual skin checks
- Look for change in shape, colour, size 7mm or more, irregular
How does measles present?
- Intial cough and fever - URTI symptoms then rash
- Rash starts behind ears and on face
- VERY infectious
- Check for Koplik spots in buccal mucosa
- Only affects unvaccinated usually
What does a measles rash look like?
Erythematous maculopapular rash, non pruiritic
Where to refer for suspected melanoma?
2 week wait for pigmented lesion clinic
How does ringworm appear?
Round
Central clearing
What is the treatment for ringworm?
- Topical clotrimazole or miconazole if isolated OTC
- Topical hydrocrotisone 1% if lots of inflammation
- Oral terbinafine if extensive
How long do fungal infections take to resolve?
- Skin 3-4 weeks
- Nails can take 6 weeks-6 months of treatment
What can be a cause of recurrent thrush?
Lichen sclerosis
Skin conditions that cause pruritis?
Scabies
Uraemia
Lichen planus
Lichen sclersosis
Nodular prurigo
Eczema
Bites
