Dermatology

Question 1

Management of mild-mod acne

Answer 1

a 12-week course of topical combination therapy should be tried first-line:
- a fixed combination of topical adapalene with topical benzoyl peroxide (differin)
- a fixed combination of topical tretinoin with topical clindamycin
- a fixed combination of topical benzoyl peroxide with topical clindamycin
topical benzoyl peroxide may be used as monotherapy if these options are contraindicated or the person wishes to avoid using a topical retinoid or an antibiotic

Question 2

What are the risk factors for squamous cell carcinoma of the skin?

Answer 2

• sun/ UV exposure
• actinic keratoses and Bowen’s disease
• immunosuppression e.g. following renal transplant, HIV
• smoking
• long-standing leg ulcers (Marjolin’s ulcer)
• genetic conditions e.g. xeroderma pigmentosum, oculocutaneous albinism

Question 3

What are the clinical features of SCC of skin?

Answer 3

• sun-exposed sites such as the head and neck or dorsum of the hands and arms
• rapidly expanding painless, ulcerate nodules
• may have a cauliflower-like appearance
• there may be areas of bleeding

Painless, bleeding, ulcerative cauliflowers on sunny sites

Question 4

How long do strawberry naevus last?

Answer 4

Usually not present at birth and rapidly develop over first month of life. Usually watch and wait unless obstructing vision or airway. They increase in size over next 6-9 months before regressing, will be fully gone in 95% of patients by the time they’re 10 years old

Question 5

What are the 4 Ps of lichen Planus

Answer 5

Puritic
Purple
Papular
Polygonal
Rash on extensor surfaces/palms/soles & genitalia, mucosal involvement common
Wickhams striae (white lines pattern on surface)

Question 6

Key difference between arterial and venous ulcers:
- Location
- Appearence
- Pain?
- Cause
- Risk Factors

Answer 6

Venous:
- Location: above malleolus
- Appearance: Shallow, irregular, granular, dark pink/red, lots of pus exudate, lipodermatosclerosis,
- Pain: pain at end of day
- Cause: venous insufficiency
- Risk factors: age, pregnancy, DVT, varicose veins, obesity

Arterial
- Location: Toes/heels/ant shin
- Appearance: Deep, punched out, necrotic, light pink or black, minimal exudate, signs of limb ischaemia
- Pain: pain at night, intermittent claudication,
- Cause: reduction in arterial blood flow
- Risk factors: PAD, diabetes, HTN, obesity, smoking