Skin Flashcards
What gene mutation may predispose a person to a BCC?
PTCH
Describe a nodular BCC
Module >0.5cm
Shiny surface
Telangectasia
Often ulcerated centrally
Describe a superficial BCC
Not raised
Rolled margin
Telangectasia
More indolent - doesn’t ulcerate
Describe a pigmented BCC
Rolled shiny margin
Telangectasia
Ulcerated
Pigmented
Describe a morphemic/sclerotic BCC
Harder to diagnose as filtrating underneath the skin at a slow rate
Harder to manage
Describe the management of a BCC
Surgical exicision: 3-4mm margin Curettage and cautery Cryotherapy Photodynamic therapy Topical imiquimod/5-flurouracil cream Mohs micrographic surgery
What are the pre-malignant variants of SCC?
Actinic keratoses
Bowen’s disease
What are high risk sites of metastasis in SCC’?
Ears
Lips
What are the clinical features of SCC?
Keratin appearance - crusty, scaly
No rolled shiny margin
No ulceration (unless aggressive)
Describe the management of SCC
Surgical excision - 4mm margin
Curettage and cautery
If pre-malignant:
Topical imiquimod/5-flurouracil cream
Cryotherapy
Photodynamic therapy
Sun protection
What determines 5y survival of melanomas?
Breslow thickness
0-1mm = 97%
1.01 - 2mm = 91%
2.01-4mm = 79%
>4.00mm = 71%
Describe acral melanoma
Hands and feet - more likely to present in people with darker skin types
Describe subungal melanoma
Underneath nails
Describe amelonatic melanoma
No pigment, can be missed, rare
Describe lentigo maligna
Pre-malignant melanoma on the face
Can develop into lentigo maligna melanoma
Describe the clinical features of a melanoma
No symmetry
Different shades
Pattern of pigmentation is different
What margin is required if Breslow depth is <1mm?
1cm
What margin is required if Breslow depth is >1mm?
2cm
Describe Gorlin’s syndrome
Multiple BCCs
Jaw cysts
Risk of breast Ca
Describe Brook Spiegler syndrome
Multiple BCCs
Trichoepitheliomas
Describe Gardner syndrome
Soft tissue tumours
Polyps
Bowel Ca
Describe Cowden’s syndrome
Multiple hamartomas
Thyroid and breast Ca
Describe pathogenesis of acne
Keratin build up in hair follicle
Increased sebum production and thickness - sebaceous glands
Propionibacterium acnes proliferation
What are the clinical features of acne
Papules
Pustules
Comedones
What type of acne is a dermatological emergency?
Acne fulminans
Describe acne inversus
Papules
Pustules
Cysts
Affects groin/buttocks
How is acne graded?
Leeds Acne Grading System
What is first line therapy for reducing the plugging of the hair follicle in acne management?
Topical benzoly peroxide
What Abx can be used to reduced the amount of bacteria in acne treatment?
Topical Abx = erythromycin/clindamycin
Oral Abs = tetracyclines, erythromycin
What can be used to reduce sebum production in acne management?
Anti-androgens OCP
What can be used in the management of severe acne vulgaris?
Oral Isotretinion Oral retinoid (concentrated form of Vit A)
How does oral risotretinoin help with the management of severe acne vulgaris?
Reduces sebum production
Reduces plugging of hair follicle
Reduces bacteria load
How long is the standard course of oral isotretinoin?
16 weeks (1mg/kg)
What is the major side effect associated with oral isotretinoin?
Teratogenicity (every girl must be on OCP and have monthly pregnancy tests)
Side effects associated with oral isotretinoin
Trivial: Dry lips Nose bleeds Dry skin Myalgia
Serious: Deranged LFTs Raised lipids Mood disturbances Teratogenicity
What are three triggers of vasculitis?
Infection
Drugs
Connective tissue disease
Describe fixed drug rash
Rash that occurs in the same area every time the same drug is used
Describe drug induced psoriasiform rash
Psoriasis-like
Well demarcated erythema with scale
Sudden onset, no FHx
What drugs are associated with a fixed drug rash?
Paracetamol
What drugs are associated with a drug induced psoriasiform rash?
Lithium
Beta-blockers
Give 2 examples of drug induced blistering disorders
Steven Johnson Syndrome
Toxic Epidermal Necrolysis
Give 2 examples of immunobullous diseases
Bullous pemphigoid
Bullous pemphigus
Describe the management of Toxic Epidermal Necrolysis
Dermatology, ITU, burns involvement Analgesia Fluid balance Special mattress, sheets Infection control, prophylaxis Non-adherent dressings Requires urological, gynaecologist and ophthalmological input
Describe erythema multiform
Self-limiting allergic reaction
Target lesions
Associated with HSV, EBV, occasionally drug
Describe bullous pemphigoid
Splits at basal layer
Distinct intact blister
Describe pemphigus vulgaris
Split is scattered through the epidermis
Don’t have an intact blister
Describe the management of an immunobullous disorder
Oral steroids (reduce autoimmune reaction) Steroid sparing agents - aziathioprine Burst any blisters Dressings and infection control Check for oral/mucosal involvement Screen for underlying malignancy
What is dermatitis herpetiformis associated with?
Coeliac disease
How can dermatitis herpetiformis be treated?
Topical steroids
Gluten free diet
Oral dapsone
Describe urticaria
Itchy wheals
Last <24 hours
Non-scarring
Can be acute/chronic (<6 weeks/>6weeks)
What are potential causes of urticaria?
Immune related - type I IgE response
Non-immune mediated -
Direct mass cell degranulation
Opiates, Abx, contrast media, NSAIDs
What treatment can be used in urticaria?
Antihistamines
Steroids
Immunosuppression
Omiluzimab
What are potential causes of acute urticaria?
Unknown Viral infections Medication - NSAIDs, aspirin, ACEi Food and food additives Parasitic infections Physical stimulants - cold, pressure, solar, cholinergic, aquagenic
Define erythroderma
Erythema affecting 80-90% of body
What are potential causes of erythroderma?
Psorasis
Eczema
Drug reaction
Cutaneous lymphoma
How can erythroderma be managed?
Treat underlying skin disorder
Supportive
Fluid/temperature balance
