Dermatology Flashcards
What is CREST syndrome?
Systemic scleroderma
Calcinosis (calcium lumps under skin on fingers), Raynaud’s disease, (O)Esophageal dysmotility, Sclerodactyly, Telangiectasia
What is seborrheic keratosis?
Start as small rough areas, over time develop thick wart like surface, waxy, scaly elevated appearance
Usually brown, can be difficulty to distinguish from melanoma
What is actinic keratosis?
Dry scaly patches of skin caused by sun damage
Pink, red or brown, skin thickening, can look like horns
Can develop into SCC if not treated
Seen in fair skinned people
What are gottrons patches?
Scaly erythematous eruptions or red patches overlying the knuckles, elbows and knees
Characteristic of dermatomyositis
Describe features of psoriasis and its epidemiology
Pink scaly plaques, particularly on extensor surfaces which may be itchy and sore
Equally affects males and females
Two peaks of ages of onset: early onset 16-22, late onset 55-60
What are first line treatments for psoriasis?
Topical agents: emollients, steroids, calcipotriol, retinoids, purified coal tar
Phototherapy
Systemic therapy: methotrexate
An anxious 19 year old woman presents with a pigmented lesion on her left inner thigh. There is no significant past medical or family history. Inspection reveals a brown purple lesion of approximately 1cm diameter with a raised smooth surface. What is the likely diagnosis?
Dermatofibroma - benign skin lesion found especially on the legs
What is a Marjolins ulcer?
Squamous cell carcinoma developing in areas of chronic inflammation such as burn sites or varicose ulcers
A 68 year old woman is referred with an ulcerated lesion on the side of her nose. It was first noticed 4 months prior to presentation and had been slowly growing. Prior to that there was crusting of the skin which had been present for some years. Inspection reveals 12mm ulcer with raised everted edge. No lymph nodes are palpable. What is the likely diagnosis? What was the crusty lesion described before it developed?
Squamous cell carcinoma
Pre lesion - actinic keratosis
What are predisposing factors for squamous cell carcinoma?
Sun exposure
Radiation exposure
Pre malignant conditions: bowens, senile keratosis, lupus vulgaris, Paget’s disease
Inherited: xeroderma pigmentosum, albinism
Chronic irritation: Marjolins ulcer, leukoplakia, varicose veins, osteomyelitis sinus
Infection: HPV 5 and 8
What is xeroderma pigmentosum?
Hereditary defect of enzyme system that repairs DNA after UV damage resulting in extreme sensitivity to sunlight and a tendency to develop skin cancer
What is lupus vulgaris?
Chronic direct infection of the skin with TB causing dark red patches with a nodular appearance, often around the face and neck
What is leukoplakia?
White patch in the mouth - area of keratosis
What is lichen planus?
Disease of skin and/or mucus membranes that resembles lichen
Autoimmune process
Who is most likely to get psoriasis and at what age?
Males and females equally likely
Peaks of onset: 16-22 and 55-60
What is pemphigoid?
Autoimmune blistering condition characterised by development of bullous like lesions which typically develop on the lower limb
What is erythema nodosum?
Raised erythematous lesions on shins
Associated with drugs - sulphonamides, oral contraceptives and penicillins
Associated with infections - mycoplasma pneumonia, RA and sarcoidosis
What is pre tibial myxoedema?
Waxy discoloured induration of skin - orange peel
Occurs in graves, Hashimoto’s and stasis dermatitis
How does a basal cell carcinoma typically present?
Small pink coloured nodule or papule with visible surface telangiectasia and pearly rolled edges
What is erysipelas?
Acute episode of cellulitis
What are 3 causes for erythema nodosum?
Inflammatory bowel disease
Sarcoidosis
Pregnancy
How does erythema multiforme present?
Acute inflammatory condition often precipitated by herpes simplex
Tender nodules surrounded by page rings - target
Give 5 features of a lesion which make you suspect skin cancer
Change in size Change in shape Change in colour Bleeding Sensory change
Name 2 features of an examination that would make you suspect a basal cell carcinoma
Pearly nodule with rolled telangiectatic edge
Ulcer