Eczema Flashcards
(20 cards)
Eczema: Definition
Eczema is a chronic atopic condition caused by a breakdown in the normal continuity of the skin barrier, leading to inflammation.
There is a genetic component as eczema (and other atopic conditions) tends to run in families, however there is no clear inheritance pattern like you might find in sickle cell disease or cystic fibrosis.
It has a huge variation in severity in that some patients can have very occasional small patches that respond well to emollients where others have a contact battle with huge areas of skin affected requiring strong steroids to get it under control.
Eczema: Features
It usually presents in infancy with dry, red, itchy and sore patches of skin over the flexor surfaces (the inside of elbows and knees) and on the face and neck.
- In infants the face and trunk are often affected
- In younger children eczema often occurs on the extensor surfaces
- In older children a more typical distribution is seen, with flexor surfaces affected and the creases of the face and neck
Eczema: Pathophysiology
The simplified pathophysiology is that eczema is caused by a breakdown in the barrier that the skin provides.
Tiny gaps in the skin barrier provide an entrance for irritants, microbes and allergens that then cause an immune response that causes the inflammation and associated symptoms.
Eczema management: Overview (5)
- Avoid irritants
- Simple emollients
- Topical steroids
- UV radiation
- Wet wraps and oral ciclosporin
- Immunosuppressants: e.g. ciclosporin, antihistamines and azathioprine
Eczema: MAINTENANCE management
They key to maintenance is to artificially maintain the skin barrier. This is done by using emollients that are as thick as tolerated as often as tolerated particularly after washing and before bed.
They are also advised to avoid activities that breakdown the skin barrier such as bathing in hot water, scratching or scrubbing their skin and using soaps and body washes that remove the skins natural oils.
Emollients and specially designed soap substitutes can be used instead of soap and body washes when showering or washing hands.
Eczema: Exacerbating factors
Some patients find that certain environmental factors play a role in making their eczema symptoms worse or better.
For example, I have heard patients say their eczema completely resolves on holiday to warm, humid countries only to flare up on returning to the cold air of Manchester.
Environmental triggers such as changes in temperature, certain dietary products (such as milk), washing powders, cleaning products and emotional events or stresses can be considered.
Eczema: FLARE management
Flares can treated with thicker emollients, topical steroids, “wet wraps” (covering affected areas in a thick emollient and applying a wrap to keep in moisture overnight) and treating any complications (such as bacterial or viral infection).
Very rarely IV antibiotics or oral steroids might be required in severe flares.
Emollients
Depending on the severity of the eczema, some patients may only require thin emollients to maintain their skin barrier, whilst others with more severe eczema require very thick greasy emollients.
The general rule is to use emollients that are as thick as tolerated and required to maintain the eczema.
Emollients: Thin creams
- E45
- Diprobase cream
- Oilatum cream
- Aveeno cream
- Cetraben cream
- Epaderm cream
Emollients: Thick, greasy emollients
- 50:50 ointment (50% liquid paraffin)
- Hydromol ointment
- Diprobase ointment
- Cetraben ointment
- Epaderm ointment
TOPICAL steroids
The general rule is to use the weakest steroid required for the shortest period to get the skin under control.
Steroids are very good for settling down the immune activity in the skin (and therefore reducing inflammation) but they do come with side effects.
Depending on the location and strength of the steroid there is also variable amounts of systemic absorption of the steroid.
The thicker the skin, the stronger the steroids required.
Only weak steroids used very cautiously should be applied to areas of thin skin such as the face, around the eyes and in the genital region. It is best to completely avoid steroids in these areas children.
TOPICAL steroids: SIDE effects
They can lead to thinning of the skin, which in turn make the skin more prone to flares, bruising, tearing and stretch marks, and enlarged blood vessels under the surface of the skin (telangiectasia).
Steroid Ladder (from weakest to most potent)
- Hydrocortisone 0.5%, 1% and 2.5% – mild
- Eumovate (clobetasone butyrate 0.05%) – moderate
- Betnovate (betamethasone 0.1%) – potent
- Dermovate (clobetasol propionate 0.05%) – very potent
Bacterial infection
Opportunistic bacterial infection is common in eczema, as the breakdown in the skin’s protective barrier allows an entry point for infective organisms.
The most common organism is staphylococcus aureus.
Treatment is with oral antibiotics (e.g. flucloxacillin). More severe cases may require IV antibiotics.
Eczema Herpeticum
A herpes simplex virus 1 (HSV-1) infection to the skin, usually covering later portions of the skin in patients with eczema. See the next section for more information.
Eczema: TYPES
- Atopic eczema
- Irritant dermatitis
- Allergic contact dermatitis
- Seborrhoeic dermatitis
Eczema: Prognostic markers associated with severe disease (5)
- Onset at age 3-6 months
- Severe disease in childhood
- Associated asthma or hay fever
- Small family size
- High IgE serum levels
Irritant dermatitis: Definition
Irritant contact dermatitis is a form of contact dermatitis, in which the skin is injured by friction, environmental factors such as cold, over-exposure to water, or chemicals such as acids, alkalis, detergents and solvents.
Treatment: avoid all irritants.
Allergic contact dermatitis: Definition
Allergic contact dermatitis (ACD) is a form of contact dermatitis that is the manifestation of an allergic response caused by contact with a substance; the other type being irritant contact dermatitis (ICD). Although less common than ICD, ACD is accepted to be the most prevalent form of immunotoxicity found in humans.
Treatment: consider patch testing and avoidance of implicated allergens.
Seborrhoeic dermattis: Definition
Seborrhoeic dermatitis is a common inflammation of the skin occurring in areas rich in sebaceous glands.
