Eczema (atopic dermatitis)

Eczema cannot be explained by any one single cause. There are likely to be a range of contributing factors.

Genetics

Genetic factors are important as eczema can run in families. Asthma and hay fever often occur together with eczema.

The skin barrier

Recent research has focused on the ‘skin barrier’. The outer layer of your skin (the epidermis) forms a barrier which helps retain moisture in the skin and protects against irritants (substances that can irritate the skin). If this barrier is not working properly, your skin becomes dry and more vulnerable (at risk) to irritants. Some people with eczema have inherited abnormalities in their skin barrier.

In people who have eczema, a number of factors can irritate the skin and cause flare-ups, including:

• exposure to soaps, detergents and bubble baths
• swimming in chlorinated pools
• overheating and sweating
• contact with woollen fabrics
• contact with grass or sand
• low humidity environments – eczema can be more severe in Perth’s dry, warm climate compared to other cities with higher humidity levels
• when babies and children become unwell with other illnesses, such as viral infections.

Food allergies

Eczema is not caused by food allergies, although many people often assume this is so. You should only change your diet under medical advice.

It is possible that some foods might worsen existing eczema in a small number of people (less than 10 per cent). Some foods, for example citrus fruits or tomatoes, can cause a local irritation where they touch your skin (usually around the mouth), but this is not a true allergy.

The incidence of eczema has increased in recent decades. Up to 20 per cent of babies may be affected.

Eczema is more common if parents or other close relatives have eczema, asthma or hay fever.

Eczema usually first appears around 3 to 4 months, but it can appear earlier.

Eczema presents with an itchy rash which is red, rough and scaly. It often occurs on a background of dry skin. When it is very severe, it can appear moist and weepy or crusted. When the eczema has been present for a long period of time, the affected skin becomes thicker than normal (lichenification).

Any area of the body can be affected, but some body sites are common:

• for babies, it often begins on the face (especially the cheeks), and can become more widespread from there
• for older children, the skin folds are typically affected – especially the front of the elbows and the back of the knees – and also the wrists and ankles.

When areas of eczema heal there may be changes to the colour of the skin. The affected area may appear lighter (hypopigmentation) or darker (hyperpigmentation). These colour changes tend to slowly improve with time. Eczema usually does not cause permanent scarring, unless it has been deeply scratched.

Eczema can affect people differently

Eczema is not a minor condition. It causes itching and discomfort, which can interfere with sleep. This can have further effects on the entire family.

Older children may become embarrassed about how their eczema looks. The itch and sleep disturbance may also cause problems with concentration and school performance.

Complications of eczema

Skin that is affected by eczema can become infected with bacteria or viruses. This can result in worsening of the eczema, together with the appearance of sores, crusts, weepy areas, pimples or boils

In severe long-term cases, untreated childhood eczema may interfere with growth and development.

It is also possible that untreated eczema may result in an increased risk of subsequent problems with hay fever, asthma and allergies. This is because allergens (any substance which might cause an allergy) may enter through the broken skin, causing the immune system to produce allergies.

Visit your doctor or an after hours GP.

Eczema can usually be recognised easily by its appearance.

The management of eczema usually involves both general skin care measures and specific prescription treatments.

General skin care

These general skin care measures should be continued long term and can help to prevent flare-ups.

• Avoid the use of soaps and bubble baths. A soap-free wash can be used as an alternative.
• There is no need to restrict showers or baths but they should be short and not too hot.
• If the skin is very dry, bath oil can be added to the bath.
• Generously apply moisturiser after a shower or bath. Thicker cream or ointment based moisturisers are usually more effective than liquid lotions.
• If swimming in chlorinated pools, rinse off and apply moisturiser immediately afterwards.
• Avoid overheating and wearing woollen fabrics next to the skin.

Prescription treatments

The most common prescription treatment is usually with topical steroids (creams or ointments containing corticosteroids). These are often referred to as ‘cortisone’ creams or ointments.

There are different types of topical steroids and they are available in different strengths. The choice of treatment will depend on how severe your eczema is and where it is on your body. Topical steroids are typically used more intensively for flare-ups of eczema, and then not used as frequently or withdrawn as the flare settles.

Parents often worry about using topical steroids on their child’s skin – they have often heard that topical steroids will damage or thin the skin or affect their child’s growth. However, these fears are largely unnecessary and can lead to the child’s eczema being inadequately treated. Provided that they are used correctly, topical steroids are very safe. Side effects from topical steroids are not commonly seen in the treatment of eczema.

Non-steroid based anti-inflammatory creams such a pimecrolimus or tacrolimus have a role in some cases.

If eczema is infected, antibiotic treatment may be needed.

In very severe or resistant cases, particularly in older children or adults, specialists may prescribe phototherapy (light treatment) or oral immune-suppressing medications.

Diet

Dietary change is not necessary unless there is a medically diagnosed food allergy.

Breastfeeding mothers of babies with eczema need not change their own diet.

There is currently no cure for eczema. Ongoing treatment is usually required. It is important to continue general skin care measures (especially regular use of moisturisers) to help prevent flare-ups.

In most cases, eczema tends to improve with age. Some affected babies will grow out of their eczema by 1 to 2, but in some cases it can persist well into childhood, and sometimes into adolescence and adulthood.