Atopic Eczema Flashcards
What is eczema and dermatitis?
- Terms often used to describe the same condition
- Non infectious, non contagious inflammation of the skin
- characterized by
1. certain clinical - erythema, scales & vesicles)
2. and histopathological changes - spongiosis
What are the different phases of eczema?
- ACUTE:
- redness swelling, papules blisters oozing, crusts - SUBACUTE:
- still red, drier, scalier, pigment changes - CHRONIC:
- lichenification, excoriations scaling, cracks
Note: sometimes all phases are present at the same time
What is erythroderma?
Eczema affects the whole body
Classification of eczema?
- endogenous - atopic
- exogenic - conrtact
Endogenous eczema?
- Seborrhoic
- Discoid - Nummular
- Dyshidrotic
- Asteatotic
- Ichtyosis
Exogenic eczema?
- CONTACT
* Toxic irritant
* Allergic
* Photosensitive
* Vaseline dermatitis - Lichen simplex chronicus
Taking a history of eczema?
- Elicit the nature, course, time of the eczema
- Enquire: atopic symptoms, general medical
conditions, travelling, profession, operation - Identify any factor in social or family history that
may be relevant – e.g.psoriasis, eczema - Record recent drugs and medications,
including topical agents, herbals. - Ask about use of cosmetics, sunexposure
Examining the skin inneczema?
- good light or use hand lens
- Gently palpate lesions to assess
texture, consistency - Observe distribution, individual lesion:
* morphology & configuration
* Localised, widespread, linear, symmetrical, peripheral-central,
flexures - extensors, sunexposed areas, groin, axilla, colour ?
* Nails, hair, mucous membranes, lymph nodes
What is atopic dermatitis?
distinctive pruritic eczematous condition of the skin
* Acute, subacute or chronic
* inflammation of dermis and epidermis
* Very heterogenous
* Pruritus, dry skin
* Symtoms may change often and fast
* May have long periods of remissions
* Always itchy = „the itch that rashes
Epidemiology of atopic dermatitis?
- genetically determined
- Often together with personal or family history
of hay fever, asthma, rhinitis, AD - Starts mostly in early childhood, 10-25% of
infants, 1-3 % of adults - Common disease in people under 25
- Underlies 80% of occupational dermatoses
- Often misdiagnosed, misunderstood and infeffectively treated
Etiology of atopic dermatitis?
Increasingly prevalent and common in industralized countries
- Theory suggests that our overall sterile modern lifestyle
- lack of exposure to parasites,
infections and bacteria creates an imbalance and immaturity for the immune system predisposing us to atopic disorders
Reduced risk for developing atopic dermatitis?
- High exposure of Endotoxins on farms
- Early attendance of Kindergardens
- Dog in the household at birth time
Higher risk for developing atopic dermatitis?
frequently use antibiotics
Features of atopic dermatitis?
- Usually recurrent exacerbations
- Duration of lesions: untreated = month to years
- Itch is the most important clinical symptom, Disturbing
quality and individual way of life in children and adults - Individual therapy and education
What is the atopic march?
the natural history of allergic diseases as they develop over the course of infancy and childhood
- food allergy > atopic eczema > allergic rhinitis > allergic asthma
What is the role of the epidermal barrier?
Tight junctions, desmosomes and adherens junctions form adhesions between the cells of the epidermis to help create a physical, permeability barrier.
Pathophysiology of acropic eczema?
Impairment of the physiology of the skin
1. Reduced activity of sebaceous glands
2. Reduced barrier function of skin
Epidermal barrier dysfunction and atopic dermatitis?
- Genetic mutations for Filaggrin (protein important for composition of the lipids of the skin)
- Genetic mutations for important Proteases have been described
- Secondary proteases: produced by inflammatory cells
- Exogen proteases:
* Dust mites
* Staphylococci
