Dermatology Flashcards
(208 cards)
What does it mean if a skin lesion is described as being ‘acral’ in its distribution?
Affecting distal areas- hands and feet
What dermatological condition do you classically associated with target lesions?
Erythema multiforme
How do annular and target lesions differ in their appearance?
Annular lesions are circle/ ring shaped (usually middle part spared)
Target lesions are concentric rings of varying colour and look like a dartboard / bullseye
When assessing the colour of a lesion, can use the term ‘purpura’ to describe a reddish/ purple discolouration of the skin. Name 2 types of purpura?
Petechiae and ecchymosis
What is key to remember about how lichenification of the skin looks?
Roughening of the skin with exaggerated normal skin lines
What distinguishes a hypertrophic scar from a keloid scar?
Hypertrophic scar = hyperproliferation of scar tissue WITHIN the wound boundary.
Keloid scar = hyperproliferation of scar tissue BEYOND the wound boundary.
Striae progress in colour from what.. to what.. to what..?
Purple -> Pink -> White
What does alopecia areata look like?
Well defined patches of hair loss with surrounding normal hair
Excess hair growth can be described as hirsutism and hypertrichosis- what is the difference?
Hirsutism is androgen-dependent excess hair growth in a female
Hypertrichosis is non-androgen dependent pattern of excessive hair growth
What are open and closed comedones more commonly known as?
Open comedones- blackheads
Closed comedones- whiteheads
The epidermis contains which 4 major cell types?
Keratinocytes, Langerhans cells, Melanocytes and Merkel cells
Tell me about UVA and UVB
UVA- longer wavelength, penetrates deeper and through window glass A = ageing (damages elastic fibres) and carcinogenic
UVB- shorter wavelength causes burning not as carcinogenic
B= burning
Outline Fitzpatrick skin types
1- always burns, never tans 2- usually burns, sometimes tans 3- sometimes burns, usually tans 4- never burns, always tans 5- brown skin 6- black skin
What is the progression from a mole (benign melanocytic naevus) to malignant melanoma?
Congenital and acquired melanocytic naevi (benign) -> atypical (dysplastic) melanocytic naevi -> malignant melanoma in situ (Lentigo malinga) -> malignant melanoma
What is malignant melanoma in situ called?
Lentigo maligna (but note that this is not the same as Lentigo maligna melanoma so do not get them mixed up!)
What are seborrhoeic keratoses and how are they classically described?
Benign epidermal skin lesions seen in older people. ‘Stuck on’ and ‘warty’ looking appearance.
What is the commonest form of skin cancer?
Basal cell carcinoma (BCC)
What are BCCs also known as?
Rodent ulcers
Where do you typically see BCCs?
Typically on the face in elderly or middle-aged patients. They mainly occur on light-exposed sites, commonly around the nose, the inner canthus of the eyelids and the temple
What are some of the risk factors for BCC?
UV exposure, history of frequent or severe sunburn in childhood, skin type 1, increasing age, male sex, immunosuppression, previous Hx of skin cancer and genetic predisposition
How fast do BCCs grow and do they metastasise?
They are a slow growing and locally invasive malignant tumour of the epidermal keratinocytes and only RARELY metastasise
What is the most common type of BCC?
Nodular
How are nodular BCCs classically described?
Small skin-coloured papule or nodule that shows fine telangiectasia and a glistening pearly rolled edge and central depression. The superficial branching telangiectasia are characteristic and are seen on dermoscopy as ‘arborizing’
What subtype of BCC more commonly occurs in younger patients? And how do these tend to present?
Superficial (plaque like). They present most frequently on the trunk as a slowly expanding pink-red patch.