Eczema management

A child with atopic eczema is more likely to go on to develop other atopic conditions such as asthma and allergic rhinitis (the so-called ‘atopic march’). Eczema is diagnosed in about 20 per cent of children during their first year of life and most children who are affected will have developed symptoms by the age of four. However, 60-70 per cent of children with eczema will experience remission by the age of 15. Relapses may occur later in life, affecting approximately 2 per cent of adults.
Eczema is diagnosed based on guidelines which are centred on the presenting clinical symptoms and patient history. A clue to the diagnosis of eczema is the presence of itch – if it doesn’t itch, it is unlikely to be eczema.

Natural history
The sites affected and the presentation of eczema varies as the patient ages. With infants, the skin shows signs of widespread xerosis (dryness) and the first sites affected are normally the cheeks, chin and forehead. For younger school children, the distribution of eczema changes to affect the flexor surfaces of the elbows and knees, the antecubital and popliteal fossae respectively. These sites will show signs of erythema and are often lichenified (ie the skin has thickened) due to constant scratching.
As children progress into adolescence, the condition can spread to the eyelids, ear lobes, scalp and neck. Although eczema can clear in many teenagers, the skin remains susceptible to eczema and they can often experience flares as they develop into young adults. Eczema can persist into adulthood and will often continue to affect areas such as the antecubital fossa, the eyelids and hands. Adults with eczema tend to have skin that is drier and more lichenified than children. The course of eczema in those affected normally follows a relapsing and remitting pattern, which can last a lifetime.

Pathophysiology
The precise cause of eczema remains unclear, although there are several possible factors responsible and it is likely to be caused by a complex interaction between genetic and various environmental factors. The term eczema originates from the Greek word ‘ekzein’ which means to ‘boil out’, and this is an apt description for the typical presentation of an acute attack. The skin becomes intensely pruritic and patients scratch their skin, resulting in visible excoriations. In the more chronic stages, the skin undergoes lichenification, which is a response to repeated scratching.
The itch associated with eczema is the most debilitating symptom and can have a profound impact upon the sufferer or their carer. Itch can lead to sleep disturbance and loss of self-esteem as sufferers worry about their appearance. Constant itching results in scratching of the skin, which causes further itching, resulting in a vicious scratch-itch cycle.

Treatment
Eczema treatment depends on its severity. NICE produced guidance on the management of atopic eczema in 2007, the key aspect of which is the use of emollients on a regular basis (irrespective of severity).

Emollients
Emollients work to ‘waterproof’ the skin. That is, they form an impervious oily barrier that prevents loss of water from the surface of the skin and entry of allergens or irritants. Emollients are available as leave-on products such as creams, ointments, lotions and sprays, as well as wash products, which are designed to be used as soap substitutes.
Some practical tips on emollient use are shown in the panel overleaf. All patients should practise ‘complete emollient therapy’, which involves the use of a soap substitute, a wash product for the bath or shower, and application of a moisturiser throughout the day.
As emollients are effectively ‘worn’ by patients, in much the same way as an aftershave or perfume, the best emollient is the one that the patient is happy to use. Greasier preparations, although more occlusive, are likely to be problematic for office-based workers who spend time dealing with paper and computers, but are less of a problem for those who work outdoors. Most patients are happier using products that contain less oil and are easily absorbed without leaving a greasy film on the skin. Unfortunately, such lighter products need to be applied more frequently.

Tropical corticosteroids
Topical corticosteroids are normally reserved for the management of an eczema flare. They work by suppressing the production of inflammatory mediators and are effective at bringing a flare under control. But adverse effects such as skin thinning have led to much ‘steroid phobia’. Nevertheless, short-term use for one to two weeks is normally sufficient to bring a flare under control without any problems.

Calcineurin inhibitors
The topical calcineurin inhibitors, pimecrolimus and tacrolimus, are immunosuppressive agents. There is little convincing evidence that they are more effective than topical steroids, although they have the advantage of not causing skin thinning and are therefore suitable for sites where there is a risk of skin thinning on prolonged use, such as the eye-lids and face.

Other treatment options

• Bandage treatments, such as wet wraps, can help protect the skin from scratching, and their occlusive nature allows for enhanced penetration of topical therapies, but the evidence base is poor.
• Oral treatments, such as the immunosuppressants ciclosporin and azathioprine, are normally reserved for more severe cases. The evidence for their effectiveness is limited, and such drugs have a number of potentially serious side effects, requiring careful monitoring.
• Antihistamines, such as chlorphenamine, are often prescribed to help relieve itching but there is little evidence that they are effective.
• Phototherapy with both UVA and UVB is often used in secondary care. Phototherapy is suitable for adults and children, but not for very young children or frail elderly patients who are unable to stand in the UV cabinet.
• Complementary/alternative therapies include Chinese herbal medicine, herbal medicine, homeopathy, hypnotherapy, massage, acupuncture and gamma linolenic acid (evening primrose oil). Although such therapies are popular with some patients, and clinical studies show some promise, in particular with Chinese herbal medicine, further work is required to evaluate such treatments.
• Probiotics based on lactobacillus can improve the severity of eczema, but further studies are required to more clearly define their role.

Dr Rod Tucker
Institute of Health Sciences,
University of Leeds, and a project
guardian for the CPPE dermatology packages

Forms of eczema

• Symptoms

• Seborrhoeic eczema;Starts as dandruff which can spread to the forehead, eyebrows, eyelids and sides of the nose. It can also spread to the chest and axillae, groin and the sub-mammary regions. Treatment is with topical anti-fungal therapy, eg ketoconazole cream or shampoo, or if the condition is more widespread, oral treatment with ketoconazole or itraconazole.
• Discoid or nummular eczema;Normally presents as coin shaped itchy and scaly inflamed lesions that tend to occur on the lower legs or arms. Although patches will clear with treatment, the lesions often re-appear or new lesions can develop.
• Pompholyx exzema; Normally seen on the lateral aspects of the fingers and the soles of the feet. Pompholyx appears as tiny flesh coloured blisters that are intensely pruritic and is sometimes worse in hot weather. The cause is unknown and treatment normally requires potent steroids.
• Asteatotic eczema; When present on the shins and lower legs, the condition looks very much like crazy-paving or a dry riverbed. Treatment involves the use of greasier emollients, although mild steroids are sometimes required if the condition becomes sore or very itchy.

• Comments
• Seborrhoeic eczema;Often present in infants as cradle cap. The condition sometimes reappears in teenagers, more so in males than females. Seborrhoeic eczema is a chronic, relapsing-remitting problem.
• Discoid or nummular eczema;Discoid eczema can affect anyone but is more common in middle-aged men. The cause is unknown and the treatment often requires potent steroids, sometimes combined with antibiotics if a secondary infection is present. Discoid eczema can take months or even years to clear completely.
• Pompholyx exzema;Also referred to as dyshidrotic eczema. Without treatment, it can last for about three weeks, but tends to follow a relapsing/remitting pattern for several months or even years.
• Asteatotic eczema;Tends to occur in the lower legs (although it can occur on the arms and torso) and mainly affects patients over the age of 60. More common in the winter months and associated with very dry skin. The cause is unknown but probably related to reduced humidity and use of soaps and shower gels.

Emollients and how to use them
Leave-on emollients such as creams, lotions and sprays are oil and water emulsions, and the higher the proportion of oil, the greasier the product feels on the skin. Most leave-on products will contain preservatives that can cause sensitivity reactions, characterised by a burning, stinging or itching sensation. In contrast, ointments do not contain preservatives and are less likely to cause sensitivity reactions. Examples of emollients in terms of greasiness are:

• Very greasy – Epaderm ointment, 50:50 WSP:LP;
• Greasy – Unguentum M, Hydromol;
• Moderately greasy – Diprobase, Cetraben;
• Light – Aveeno, E45.