Dermatology Flashcards
What is the most common type of exzema?
Atopic excema
What is atopy?
overactive immune response to environmental stimuli
What is the atopic march?
tendency to 3 commonly linked conditions:
ECZEMA, ASTHMA and HAYFEVER
Atopic exzema is caused by an abnormality in the expression of which protein?
Abnormality in filaggrin expression.
Distribution of atopic exzema
- Infancy
- Typically starts on the face/neck (cheeks common), can spread more generally
- Older children
- Flexural pattern predominates (antecubital fossae, popliteal fossae, wrists, hands, ankles)
Childhood exzema flares can be associated with:
- Infections/viral illness
- Environment: central heating, cold air
- Pets: if sensitised/allergic
- Teething
- Stress
What type of exzema is this?
Which parts of the body does it affect?
What age group does it affect?
Treatment
- Seborrheoic dermatitis
- Mainly scalp and face
- Often babies under 3 months, usually resolves by 12 months
- Emollients, antifungal creams, antifungal shampoos, mild topical steroids
What type of exzema is this?
- Discoid exzema
- Scattered annular/circular patches of itchy eczema
- Can occur in this pattern as part of atopic eczema or in isolation
What type of exzema is this?
Which body part is it found on?
Characteristics
- Pomphylx eczema
- Hand and foot exzema
- Characterised by vesicles; can be intensly itchy
What are the two types of exogenous exzema?
- Allergic eczema
- sensitised to allergen
- Type IV hypersensitivity - patch testing helpful
- Irritant eczema
- repeated contact; water and soaps, touching irritant foods; citrus, tomatoes, chemical irritants
Symptoms of immediate reactions from food allergy
- lip swelling
- facial redness/itching
- anaphylactoid symptoms
(Type 1 reaction)
Symptoms of late reactions to food allergy
- worsening of eczema 24/48 hours after ingestion
- GI problems
- Failure to thrive
- Severe eczema unresponsive to treatment
- Severe generalised itching - even when the skin appears clear
(Type 4 hypersensitivity)
Tests for immediate reaction food allergies
- Blood test for specific IgE antibodies (RAST)
- Skin prick testing
What are some of the causes of immediate reaction allergies
- Commonest: milk, soy, peanuts, eggs
- Airborne allergens - house dust mite, pet dander, pollens
How would you confrim the allergy for late reaction food allergies?
- Dietary restrictions/eliminations 6-8 weeks
- Eliminate one food at a time