Dermatology Flashcards
Pathophysiology of eczema
Immune response to irritants/allergens
Causes inflammation in the skin
This causes breakage in the skin barrier
This results in water to escape and the skin becomes dry and itchy
Features of eczema
Pruritis
Scaling/dryness
Erythema
Thickening of lichenified skin - occurs in chronic eczema
Most common type of eczema
Atopic eczema - most commonly occurs in childhood
What factors exacerbate eczema
Stress Sweat Climate Infection House dust
If atopic eczema is present in a child, does it progress to adulthood
10-20% children have it, only 1-2% of adults do
As children grow, skin disease tends to improve
It may disappear all together or remain dry and easily irritated
Which protein is mutated in 50% of cases of severe eczema
Filiggrin (FLG)
Which area of the body is eczema more common
Flexure surfaces
Management of eczema
Avoid triggers
Emollients - used generously e.g, diprobase
Topical steroids - applied sparingly 30 mins after emollients
In more severe eczema can use topical calcineurin inhibitions e.g, tacrolimus or phototherapy
Information to give patients about applying emollients
Apply generously Use clean spoon or spatula to remove from tub to reduce risk of infections Apply in downwards motion Apply after showering Apply before steroids
What is eczema herpeticum?
Skin infection by herpes simplex virus 1/2 seen in patients with atopic eczema
Potentially life threatening
Presents as rapidly worsening painful eczema with punched out erosions
Management of eczema herpeticum
Hospital admission
IV aciclovir
What is pompholyx eczema
Type of eczema affecting hands and feet
May be precipitated by humidity (sweating and high temps)
Presents as small blisters on palms and soles
What is seborrhoeic dermatitis
Type of eczema
Caused by fungal infection
Presents with eczematous lesions on scalp, periorbital, auricular and nasolabial folds
Management of seborrhoeic dermatitis
Topical antifungals e.g, ketoconazole
What is psoriasis
Autoimmune skin condition
Inflammation in the skin leads to rapid turnover of keratinocytes (only take 3-5 days to migrate to surface, should take 23)
This leads to accumulation of immature skin cells on the surface which leads to to scaly thick skin
What is the auspitz sign in psoraisis
If skin of psoriasis is scraped off it reveals dilated blood vessels underneath
This accounts for much of the erythema in psoriasis
Features of psoriasis
Red, scaly silver patches found on skin (commonly extensor surfaces)
Nail changes - pitting, onycholysis
Arthritis may also be present
Types of psoriasis
Plaque - most common
Flexural - in flexor folds, in contrast to plaque, skin is smooth
Guttate - transient teardrop rash occurring in response to streptococcal infection
Pustular - commonly occurs on palms and soles
Exacerbating factors for psoriasis
Trauma
Alcohol
Medication - beta blocks, lithium, antimalarials
Streptococcal infection - may trigger guttate psoriasis
Management of psoriasis
Emollients
Topical potent steroid e.g, betnovate
Topical vitamin D analogue e.g, calcipotrol
For more severe non responsive to initial therapies can use coal tar preperations or dithranol
Management of psoriasis which is non responsive to topical therapies
Phototherapy - UVB or PUVA light 3x a week
Systemic treatment - methotrexate, biological agents
Pathophysiology of ache
Sebaceous glands in hair follicles become blocked and inflamed
Hormones e.g, androgens can increase the amount of oil produced in the glands which can cause them to become blocked
Clinical Features of acne vulgaris
Comedomes - open and closed
Inflammation
Papules
Pustules
Difference between open and closed comedomes
Open - blackheads
Closed - white heads (plugged follicles)
