Eczema and Dermatitis Flashcards
(55 cards)
Which group is Atopic eczema most common in
Children
Most start in early infancy
What factors contribute to eczema
Genetic and environmental
Often involves mutation in the filaggrin gene, overproduction of cytokines or IgE
More common in Western and industrialised areas
What is the biggest trigger for an eczema breakout
Stress
What conditions is atopic eczema related to and why
Asthma (2+) and hay fever (7+)
Often people with eczema have overreacting Th2 cells that make them sensitive to other triggers
What would be seen under the microscope in skin with eczema/dermatitis
Spongiosis - oedema between keratinocytes
Varying degrees of acanthosis
Inflammatory cell infiltrate - superficial
What are the general signs of eczema/dermatitis
Itch Ill defined rash Erythema Scaling Clustered papulo-vesicles
How do you test for contact dermatitis
Patch testing
Use many patches with the most common allergens
May add extras based on history - e.g. patients own products
Assessed at day 3 and 5
Describe irritant dermatitis
Very common
Non-specific physical irritation rather than an allergy - direct irritation from a substance
e.g. excessive soap/water exposure
May be caused by occupation
How common is atopic eczema
Affects up to 25% of school aged children
What other atopic diseases is eczema associated with
asthma, allergic rhinitis (hayfever), food allergy etc
What is the normal distribution of atopic eczema
Flexural
In crook of elbow, behind knees etc
In infants it is often on their face and extensors!
What are some chronic changes that occur with atopic eczema
Lichenification
Excoriation
Secondary infection
What factors are thought to cause/impact eczema
Multiple genetic and environmental factors
- skin barrier function
- environment
- immunology
Where does photosensitive eczema present
In sun exposed areas
E.g. hands, above collar
What is discoid eczema
The classic eczema erythema and lesions present as well defined circles/ovals
Very itchy
Will be scattered - often on legs
Patients are often atopic
What is stasis eczema
occurs secondary to increased hydrostatic pressure, oedema and red cells being pushied out of vessels
Dry skin forms over varicosed veins
What is the common name for seborrheoic dermatitis in infants
Cradle cap
What is pompholyx eczema
Subtype of eczema
Spongiotic vesicles form - itchy, watery blisters
Skin is itchy with burning sensation, then blisters form. Skin may then dry and peel
Commonly on hands and feet
May be due to irritants
A rash that is never itchy is unlikely to be dermatitis - true or false
True
Dermatitis and eczema are synonymous terms - true or false
True
They both indicate skin inflammation
Describe the acute phase of dermatitis
Fluid accumulation in epidermis - spongiosis
Vesicles and bullae may be seen
Describe the chronic phase of dermatitis
The affected area becomes drier and crustier
Thickened skin with prominent skin markings (lichenification)
What is contact dermatitis
Dermatitis secondary to external agents - exogenous
May be irritant ( non-immune mediated) or allergic.
Which patients are at higher risk of developing contact allergy
Chronic skin conditions (particularly leg ulcers) necessitating prolonged exposure to topical treatments ( under occlusion in some cases)
Certain occupations due to repeated exposure to potential allergens - building trade, hairdressing etc
