Eczema Flashcards
List 4 reasons why it is important to learn about eczema
Common - 24% children
Prevalance is rising
chronic
costly
Define eczema
An inflammatory skin condition commonly affecting flexural areas
Does eczema affect flexural or extensor areas?
flexural
Define atopic eczema
an itchy skin condition in the last 12 months + 3 of the following
- onset before age 2
- history of flexural involvement
- history of generally itchy skin
- atopic diseases eg hayfever, asthma
- 1st degree relative if under 4
What gene is implicated in atopic eczema?
filaggrin gene - sticky protein in the skin
Genetic role in atopic eczema
atopic diseae
filaggrin gene
Environmental factors in atopic eczema
atopy
epidermal barrier dysfunction
3 steps of atopic eczema pathogenesis
intracellular oedema within epidermis due to inflammation
Thickening of epidermis
Inflammation
List 4 potential causes of acute flares of atopic eczema
viral illness
stress
environment eg cold, heat
Food allergies
Clinical features of atopic eczema
ithc, red, scaling, papules and vesicles
flexural
babies faces
Chronic changes in atopic eczema
plaques and fissuring
3 types of exogenous eczema
contact dermatitis
lichen simplex
Photoallergic
7 types of endogenous eczema
atopic discoid venous seborrheic dermatitis pompholyx juvenile plantar dermatitis asteatotic
What type of hypersensitivity reaction is allergic contact dermatitis? What does this mean?
type 4
delayed - can happen 2 or 3 days after exposure
Explain the immunology of allergic contact dermatitis
APC taken allergen to lymph node to naïve T cells
Clonal expansion and next encounter allergen will have mast cell degranulation, vasodilation and neutrophils
How is the skin injured in irritant contact dermatitis? (3)
friction eg micro trauma or accumulative
Environment eg cold, chemicals
occupation eg hairdresser, cleaners
Explain the concept of patch testing
potential allergens applied to the skin not using needles on Monday and removed Wednesday and look at Friday
Where is seborrheic dermatitis found?
scalp and flexures
Who is affected by seborrheic dermatitis?
<6 months old - infants
What happens in chronic dermatitis with yeast?
malassezia yeast increased in scaly epidermis of dandruff
Appearance of chronic dermatitis
red, sharply defined lesions with greasy looking scales in places with a lot of sebaceous glands
How is chronic dermatitis treated and if it is severe what would we consider?
anti yeast
HIV test
Appearance of discoid eczema
circular plaques found at sites of trauma or irritation
Where is vesicular eczema found?
palms and soles
What can the resolution of discoid eczema include?
desquamation
Appearance of asteatotic eczema
very dry skin with cracked scaly appearance especially on the shins
Causes of asteatotic eczema
climate - heat, excessive washing
How does venous eczema present?
oedema of lower leg and ankle
resolution of this can help
Cause of eczema herpeticum
disseminated HSV infection
Treatment of eczema herpeticum
antivirals, secondary bacterial infection treatment
Treatments of eczema - ALOT!
patient education avoidance emollients soap substitutes intermittent topical steroids antihistamines anti-microbials calcineurin inhibitors eg tacrolimus
Treatment of severe eczema
UV light
immunosuppression eg ciclosporin, methotrexate
Explain the difference between ointment, cream and lotion
ointment - greasy
creams - lighter
lotions - watery
Side effects of eczema treatment
steroid striae
telangectasia