Dermatology Flashcards
Which skin cancers can metastasise?
Melanoma and squamous cell carcinoma
First-line medication for non-bullous impetigo?
Hydrogen peroxide cream.
Describe the typical features of impetigo
‘Golden’, crusted skin lesions typically found around the mouth.
Alternative treatment for impetigo than hydrogen peroxide cream?
Topical fusidic acid.
How long should children with impetigo be excluded from school?
Until the lesions are crusted and healed or 48 hours after commencing antibiotic treatment.
Which conditions are seborrhoeic dermatitis associated with?
HIV and Parkinson’s disease
Describe the aetiology of seborrhoeic dermatitis
Caused by an inflammatory reaction related to a proliferation of a normal skin inhabitant, a fungus called Malassezia furfur.
Describe the typical features of seborrhoeic dermatitis
- Eczematous lesions on sebum-rich areas, such as scalp (dandruff), periorbital, auricular and nasolabial folds.
- Otitis externa and blepharitis may develop.
First-line treatment for scalp seborrhoeic dermatitis?
Ketoconazole 2% shampoo.
What is the most common skin cancer in renal transplant patients?
Squamous cell carcinoma.
Describe the appearance of squamous cell carcinoma
Indurated (firm), nodular/plaque-like, frequently ulcerate and surrounding tissue often inflamed.
Describe the appearance of actinic keratosis
- Found on sun-exposed sites and have a scaly surface without induration.
- They tend to be soft.
- Small, crusty or scaly lesions that may be pink, red, brown or same colour as skin.
Describe the appearance of basal cell carcinomas
Initially translucent or shiny nodules with pearly rolled edges and peripheral telangiectasia on sun-exposed sites e.g. head and neck. Later may ulcerate leaving a central ‘crater’.
Describe appearance of seborrhoeic keratosis
Benign pigmented lesions which have a warty ‘stuck-on’ appearance.
Describe the step-wise approach to chronic plaque psoriasis
- First-line: potent corticosteroid applied once daily plus vitamin D analogue applied once daily.
- Second-line: if no improvement after 8 weeks then offer a vitamin D analogue twice daily.
- Third-line: if no improvement after 8-12 weeks then offer either a potent corticosteroid twice daily for up to 4 weeks OR a coal tar preparation applied once/twice daily.
Describe the secondary care management of chronic plaque psoriasis
- Phototherapy - narrowband UVB light.
- First-line: oral methotrexate.
- Ciclosporin.
- Systemic retinoids.
- Biological agents e.g. infliximab.
Management of actinic keratosis?
Fluorouracil cream
Which drug is most suitable for long-term use in psoriasis?
Calcipotriol (vitamin D analogue)
An area of rapidly worsening painful eczema is an early sign of what?
Eczema herpeticum
What causes eczema herpeticum?
HSV
Treatment of eczema herpeticum?
IV aciclovir (hospital admission)
Describe Stevens-Johnson syndrome
A severe systemic reaction affecting the skin and mucosa that is almost always caused by a drug reaction e.g. sulphonamides.