Author: Dr Roy Palmer
Most types of eczema cause itch. In some cases this can be intense and debilitating, and interfere with sleep and ordinary day-to-day activities. Sometimes eczema is not particularly itchy but is a concern because of the appearance.
The commonest type of eczema is atopic eczema. ‘Atopy’ is the tendency of some people to develop eczema, asthma and hay fever. Atopic eczema is very common in infants; approximately 1 in 6 children in the UK develop it. It has become much more common over the last few decades and the reason for this is not known. One theory is the ‘hygiene hypothesis’, which states that in the western world we now lead lives that are so clean that our immune system is not exposed to parasites, etc, while we are in our mother’s womb and in the first few months of life. The immune system therefore reacts inappropriately to everyday allergens like house dust mite.
Fortunately most cases of eczema can be managed with moisturisers, changes to daily routine, the safe use of steroid creams, and sometimes the use of treatments called calcineurin inhibitors (eg. Protopic ointment). In many cases the treatment that works most effectively is topical steroids, of the right strength and for the right duration. In infants, the condition sometimes responds very well to removal of allergens, in particular cow’s milk protein, but this is a complex process and unfortunately such avoidance rarely makes a significant difference in adults. Children usually grow out of cow’s milk protein allergy. The prognosis for infantile eczema is very good; infants usually grow out of it during their childhood. Rarely, powerful treatments are required, especially in adults, such as ciclosporin or methotrexate. In the next few years a new array of ‘biological’ treatments for eczema are going to become available. They will be very expensive but are likely to be highly effective.
Adults can suffer from atopic eczema, but they also suffer from a variety of other types of eczema including discoid eczema, varicose eczema, allergic contact dermatitis and seborrhoeic dermatitis. Discoid eczema manifests as very itchy circular raised inflamed areas, usually on the front of the legs and the back of the arms. Varicose eczema occurs when the veins in the legs are not working effectively; the eczema appears above the ankles. Allergic contact dermatitis occurs when a person becomes allergic to something that is coming into contact with their skin, for example nickel. Patients with nickel allergy notice that contact with, for example, costume jewellery results in eczema. If allergic contact dermatitis is suspected then I perform a type of allergy test called ‘patch testing’.
Seborrhoeic eczema usually affects the scalp and face, and can also affect the armpits, chest, groins, and sometimes other areas. In some people it is aggravated by a yeast present on the skin, but unfortunately anti-yeast treatments are sometimes not particularly effective. In such cases the eczema can usually be treated very effectively in other ways, although scalp seborrhoeic eczema can be hard to treat.
The National Eczema Society (http://www.eczema.org) is a good source of information about eczema.