Eczema Flashcards
What is atopic eczema (atopic dermatitis)
Inflammatory skin condition commonly affecting the flexural areas
Multiple types and a spectrum of severity
Can be induced by wide range of external or internal factors
What causes eczema?
Barrier dysfunction + inflammation
Combination between genetics, immunology, environment
What is the epidemiology of eczema
Most commonly appears in babies and children, by adult life 60% have cleared
Increasing prevalence
What is the definition (classification) of atopic eczema
An itchy skin condition in the last 12 months
PLUS 3 of the following:
- onset before age of 2
- history of flexural involvement
- history of generally dry skin
- history of other atopic disease (e.g. asthma, hayfever, food allergy)
- if <4yrs history in 1st degree relative
What is the pathogenesis of eczema
genetics (atopic family history, filaggrin gene)
Epidermal barrier dysfunction (caused by genetic changes)
Environmental factors (chemicals, temperature, hand washing etc.)
Immune system dysregulation (T-cell activation, greater pro-inflammatory cytokine release)
What is the pathology of atopic eczema (3)
Spongiosis (intercellular oedema) within the epidermis
Acanthosis (thickening of the epidermis)
Inflammation - thickening of peri vascular lymphohistiocytic infiltrate
Clinical features of atopic eczema
ITCH!!!
Distribution (flexures, neck, eyelids, face, hands, feet)
- tends to spare nappy area
Acute changes (pruritis, erythema, scale, papules, exudate, crusting)
Chronic changes (lichenification, plaques, fissuring)
What is allergic contact dermatitis
Type 4 hypersensitivity (t-cell mediated)
(Reacting to the metal in the jeans)
What is irritant contact dermatitis
Injury to the skin by:
Friction (micro-trauma, cumulative)
Environmental factors (cold, over-exposure to water, chemicals)
Often seen through occupation (cleaners, NHS staff, hairdressers)
How is contact dermatitis investigated
Patch testing
What does patch testing involve
Potential allergens applied to the skin
Applied Monday
Remove Wednesday
Re-assess Friday
How is eczema treated (7)
Patient education (explain skin barrier dysfunction, inflammation due to overactivation of immune system)
Avoid causative/exacerbating factors
Emollients (moisturisers)
Soap substitutes (reduce bacterial colonisation & less harsh)
Intermittent topical steroids
Antihistamines/antimicrobials
Calcineurin inhibitors
what is the treatment for sever eczema (3)
UV light
Immunosuppression
Biologic
