Eczema Flashcards
How many children are diagnosed with eczema
24%
Atopic eczema prevalence is rising
What is atopic eczema
Its an inflammatory skin condition most commonly seen in flexural areas. (usually caused by a barrier dysfunction)
What is the pathophysiology of atopic eczema
The skin barrier is disrupted, antigens get into the dermis which activates T cells - this gives inflammation, itch and redness
How many adults have eczema
60-75% of eczema has cleared by the time patients reach adulthood
overall 4% of adults in western countries
Definition of atopic eczema
An itchy skin condition in the last 12 months with 3 of: onset before 2yrs, flexural involvement, general dry skin, history of other atopic disease, history in 1st degree relatives if <4yrs.
Which gene is effected in eczema
Filaggrin gene (plays a key role in barrier function of epidermis).
What is spongiosis
intercellular oedema within the epidermis
what is acanthosis
thickening of the epidermis (due to persistent scratching)
features of Acute eczema on histology
intercellular oedema and infiltration of lymphocytes, neutrophils, histiocytes and eosinophils
Features of chronic eczema on histology
the level of oedema is low but the levels of acanthosis (thickening of epidermis) is high, there might also be fibrosis
Acute eczema signs
itch, erythema (redness), scales, papule, exudate, crusting
Chronic eczema signs
Thickening of the skin, plaque formation, fissuring (deep cracks in skin) - leaks exudate fluid and risks infection
Most common sign in eczema
Pruritis
Where will you see eczema on children
in flexural areas and around the mouth/face due to drooling
What is allergic contact dermatitis
its different from atopic eczema because its not chronic. Only occurs when in contact with allergen.
Type 4 hypersensitivity
Causes of allergic contact dermatitis
friction, cold, metals, water, detergents, acids, often Brought on by occupation (eg cleaner)
how to assess allergic contact dermatitis AND eczema
allergen patch testing
What is seborrhoeic dermatitis in infants
an excessive discharge of sebum which crusts up.
often clears within weeks of treatment. Child is happy as there is no associated itch.
What is seborrhoeic dermatitis in adults
a type of chronic dermatitis usually due to a yeast imbalance on the skin - causes seborrheic dermatitis.
In places with rich sebaceous glands (scalp, face)
How should seborrhoeic eczema be treated
with anti yeasts (ketoconazole). Consider HIV testing.
What is discoid eczema
circular plaques of eczema in middle aged patients (often had eczema as a child)
What is pompholyx/vesicular eczema
eczema on the palms and soles with water blisters
What is asteatotic eczema
very dry skin that gives a cracked and scaly appearance. Associated with older skin as your skin ages - it dries and thins. (excessive washing - strips natural oils from skin)
What is venous eczema
eczema usually in the lower leg when their is insufficiency of blood blow
What is eczema herpeticum
A viral infection due to herpes simplex 1 and 2. Fever and unwell. Causes itchy clusters of blisters and erosions.
Treatment of eczema in general
- avoid exacerbating factors
- use emollients
- use soap substitutes
- topical steroids (for inflammation) - hydrocortisone
- Antihistamines
- Calcineurin inhibitors (good in chronic eczema)
Treatment of severe eczema
UV light, immunosuppression, biologics
