Dermatology Flashcards
What is psoriasis?
Chronic inflammatory skin disease due to hyperproliferation. Epidermis is hyperproloferative.
Triggers of psoriasis
Stress Drugs - lithium, NSAIDs, b-blockers Alcohol Smoking Obesity Infections
Signs and symptoms of psoriasis
Itchy - less itchy than eczema
Red, demarcated patches covered in scales
Most common type of psoriasis and its features
Chronic plaque psoriasis (90% of cases)
Symmetrical, well-demarcated patches on the extensor surfaces of limbs, knees, sacrum
Silvery scales
What are the features of flexor psoriasis?
Patches of psoriasis on flexor surfaces - under arms, sub mammary areas, umbilicus
Less scaly due to friction and moisture at these sites
What are the features of guttate psoriasis?
Large number of small plaques <1cm over the trunk and limbs
Seen in the young
Commonly occurs after streptococcal URTI
Features of pustular psoriasis
Paloplantar psoriasis
Yellow-brown pustules on psalms and soles
Features of generalised psoriasis
also called eryhtodermic psoriasis
Systemic upset - fever, increased WCC, dehydration
Medical emergency
>90% body area
Investigation for psoriasis
Clinical diagnosis Examine patients wntire body Only do skin biopsy if needed Psoriasis area and severity score Dermatology life quality index questionnaire Assess cardiovascular risk
What is the pathogenesis of acne vulgaris?
Narrow follicles of vellum hair (fine body and facial hair) become plugged, causing comedomes. These allow propinocbacterium acnes to proliferate, leading to an inflammatory response and more severe lesions
Features of acne
Comedones - open = blackheads, closed = whiteheads
Paul’s, pustules, nodules, cysts
Usually on face, back, chest where sebaceous glands are rich
Give some Conservative management of acne
Wash twice with soap Do not scrub lesions Avoid excessive makeup Use emollient if skin dry Promote mental health Dispel myths (dirty, infecious)
What is the initial management of acne?
Single topical agent - benzoyl peroxide, or topical retinoid (isotretinoin).
Otherwise try azelaic acid
Treatment can be up to 8 weeks
Someone has tried topical benzoyl peroxide for acne. Not worked, whats next?
Add topical antibiotics - erythromycin
Alternatively, combine benzoyl peroxide and topical retinoids
Someone tried a combination of benzoyl peroxide and topical retinoids for acne but hasn’t worked. What’s next?
Oral antibiotics, should be used with topical agent (benzoyl or isotretinoin)
Last choice treatment for acne
Oral isotretinoin
What are the cautions of oral isotretinoin?
Dry lips and skin
Teratogenicity
Depression
Most common type of skin cancer
Basal cell cancer
Risk factors for basal cell cancer
Age and sex (elderly males) Previous BCC Sun damage Repeated sun burn Fair skin, blue eyes, blond/red eye
Presentation of basal skin cancer
Nodular- pearly nodule
Superficial- red scaly plaques
Morphoiec - mid facial sites, waxy, scar with indistinct border
Treatment of basal skin cancer
Excision Superficial skin surgery Cryotherapy (freezing) Photodynamic therapy Topical imiquimod or fluorouracil
Management of actinic karatoses
Prevention of further risk - sun block Fluorouracil cream - skin will become red and inflamed - sometimes topical hydrocortisone is given following Topical diclofenac for mild Topicsl imiquimod Cryotherapy Curettage
Seborrhoeic dermatitis associations
HIV
Parkinsons disease
Features of seborrhoeic dermatitis
Eczematous lesion on the sebum-rich areas - may cause dandruff, periorbital and nasolabial folds
Otitis external and blepharitis are may develop
Management of seborrhoeic dermatitis
Scalp - over the counter preparations- zinc pyrithione and tar
Preferred second line - ketoconazole
Face and body - topical antifungal (ketoconazole) topical steroids - should periods
