eczema

What is eczema?

Eczema, also known as atopic dermatitis, is a disease caused by inflammation of the skin and the skin's inability to retain adequate moisture. The result is a dry and very troublesome rash, which may occur on almost any part of the body.

In normal, healthy skin, which is pliable and elastic, a controlled amount of water is permitted to pass through the layers of the skin to ensure that the outermost areas remain properly hydrated. This helps to maintain a healthy skin barrier. Typically, the skin barrier has a water content of 10-20 per cent. When the water content in the skin barrier drops too low, the natural skin barrier function is impaired. As a result, the skin may become more susceptible to skin disease and more sensitive to the repeated use of water, detergents and other irritants.

What causes it?

See your doctor to find out what is triggering the eczema. You may need a referral to a specialist.

Certain substances or conditions called trigger factors can cause dermatitis to flare. These trigger factors can be:

• Irritants such as wool, skin infections, dry skin, low humidity, heat, sweating or emotional stress.
• Allergens such as dust mites, pollen, moulds or foods. Consultation with your doctor may be helpful in identifying the triggers.

The infant with atopic dermatitis is more likely to be allergic to food than other children are. There is at least a 40 to 50 per cent chance that food allergies may be triggers if your child has moderate to severe eczema.

The foods responsible for 90 per cent of these reactions are egg, peanut, milk, soy, wheat, fish, nuts and shellfish. Salicylates and some preservatives can also trigger eczema.

What are the symptoms?

Symptoms typically begin during infancy. They include cracks behind the ears and a dry, itchy, scaly rash on the inside of the elbows, backs of the knees, cheeks and sometimes other body areas, or they can be small bumps or blisters. Weeping, oozing and crusting may suggest the presence of secondary infection. The itch can be so intense that sufferers feel compelled to scratch until the skin bleeds. Infants often find relief by aggressively rubbing their faces against the cot mattress or any other hard surface.

Who is most likely to get atopic dermatitis?

Atopic dermatitis is partly genetically determined. As in all other atopic (allergic) diseases, even where there is no family history of allergy, a child still has 5 - 15 per cent chance of developing allergies. A child with one parent who has allergies has a greater than 1 in 4 (25 per cent) chance of having some form of atopic disease. A child with both parents who have allergies has a 50 - 60 per cent chance of having atopic dermatitis (eczema), asthma, food allergy or hay fever. When both parents have the same allergic disease the risk increases to as high as 80 per cent. Approximately 4 to 10 percent of all children have eczema.

Can eczema be cured?

Atopic dermatitis cannot be cured but in some people it improves naturally, especially as children get older. It can be controlled with consistent treatment and avoidance of trigger factors and protecting the skin from irritants. Talk to your specialist about allergy testing to try to identify triggers.

How is it treated?

• Moisturising the skin through the use of proven emollients.
• Steroid ointments to stop and control inflammation.
• Prescribed antihistamines to treat the itching.
• Avoidance of or reducing exposure to known irritants and allergens, environmental and/or dietary.
• Antibiotics in case of infection.

The key to treatment is rehydrating or effectively moisturising the skin. There are a number of options, which can be used as moisturisers. eg ointments, creams, lotions and combination cream/ointment preparations. It is important to find a product that will suit your skin and not cause further irritation or allergic reaction. Ointments have very high oil content and, in general, provide a barrier to water loss as well as rehydrating the skin. They can, however, be greasy and sticky. Creams and lotions have high water content and little oil and are designed to treat wet, weepy conditions. They are pleasant to use, but often do not provide a sufficient barrier against water loss and can lead to a further drying out of the skin. Products that combine water and oil will apply easily like a cream and have the rehydrating properties of an ointment.

Peanut oil in skin creams

We do not recommend the use of lotions and creams containing peanut oil, particularly in children. Research suggests that at-risk infants and children can become sensitised to peanuts via minute amounts of peanut protein absorbed through the skin from creams and lotions containing peanut oil. Even refined peanut oil is believed to contain enough protein to sensitise an at-risk child. This is a particular concern for children with eczema, as eczema is often the fist sign that a child has an allergic predisposition. These children are also at increased risk of sensitisation because allergens are more easily absorbed through broken inflamed skin.

Many commonly available nappy rash creams and bath products contain peanut oil, also called “arachis oil”. Some nipple creams also contain peanut oil. Be particularly wary of “natural” products, as these are more likely to contain “cold-pressed” oil. Oil processed this way contains significantly more peanut protein than refined oils. Be aware that the term “hypoallergenic” usually only means that the product has a reduced alcohol or fragrance content.

Manufacturers rarely print a complete ingredient listing on the label, so how do you know the brand is safe to use? Call the manufacturer of your favourite creams and lotions and ask if nut, peanut or arachis oil is used in their product.

Can it be prevented?

The Australasian Society of Clinical Immunology and Allergy (ASCIA) note that if your child has a strong family history of allergic disease, it makes sense to do what you can to prevent him or her from developing allergic diseases. It should be emphasised, the society writes, that even if you apply the following suggestions, there is still a chance that the high risk child will develop allergies:

• Smoking: Do not smoke during pregnancy, in the presence of the child or in enclosed spaces where the child will sleep or play.

• Breastfeeding: Where possible, breast feed your child. Not only does breastfeeding provide a nutritious and balanced food source for your baby, it also provides protection from infections of the gastrointestinal tract and may prevent the development of allergic diseases. Dietary restrictions during breastfeeding (or pregnancy) are not recommended.

• Formula: If it isn't possible to breastfeed, a hydrolysed (hypo-allergenic) formula rather than conventional cow's milk formula is recommended in the first six months of life. Although both extensively hydrolysed and partially hydrolysed formulas have been shown to have protective effects, only partially hydrolysed formula is available in Australia and New Zealand without prescription. Extensively hydrolysed formula is more expensive and are usually reserved for infants with established cow's milk allergies. Soy and Goat's milk formulae are not recommended for the prevention of food allergy.

• Diet: Delay the introduction of solid foods until the child is six months of age. Although there is currently no evidence that dietary elimination after the age of six months has a preventive effect it has been common practice to avoid potentially allergenic foods such as egg and milk until 12 months of age, and peanuts, nuts and shellfish until after two to four years of age. This practice is based on a theoretical benefit to protect an "immature immune system". As there is no evidence that selectively avoiding these foods during early life is harmful, many families choose to follow this practice while further research is done to assess the potential benefits.

• House dust mites: Although measures to reduce house dust mite (HDM) exposure show benefit in patients with established allergic disease it is still not clear if reduced exposure will prevent the development of new disease. HDM avoidance measures in pregnancy and early infancy may delay the onset of allergic disease but the effects are inconsistent and the long-term effects are not known. In children who do go on to develop allergic disease associated with sensitivity to house dust mites (as assessed by an allergy specialist) avoidance measures are strongly recommended.

• Pets: At this stage, there is no consistent evidence that either exposure to or avoidance of pet allergens will prevent the development of allergic disease. Although some studies have associated pet exposure to increased allergy risk, others have shown a protective effect. If a family already has pets it is not necessary to remove them for the purposes of allergy prevention. However, it is also not recommended to get new pets for the purposes of allergy prevention. In children who do go on to develop allergic disease associated with sensitivity to pets (as assessed by an allergy specialist) avoidance measures are strongly recommended.

 Sensitivity to temperature

Are children with atopic dermatitis more sensitive to heat or cold? Yes, the skin of these children does not regulate body temperature normally. They are sometimes more sensitive to hot and cold than others around them are. What feels comfortable to you may feel too hot or too cold to your child.

Tips for keeping atopic dermatitis under control

• Avoid wearing wool or rough fibres when holding your child.
• Avoid perfumed powders, soaps, detergents and contact with some cosmetics and toiletries.
• Minimise stress and anxiety.
• Keep nails short and use a nail file instead of clippers or scissors.
• Provide cotton gloves/mittens and socks to protect skin against scratching especially at night.
• Use 100 per cent cotton clothing.
• Remove name tags from clothing to prevent irritations to neck.
• A plastic bag filled with ice cubes next to the skin helps to relieve itching.
• Children with severe eczema can benefit from being smothered in emollients and wrapped in wet bandages. This helps them to sleep.
• Use cotton gloves/or cotton lined rubber gloves to protect your hands. Apply an emollient/moisturising cream before wearing gloves.
• Maintain humidity levels at a comfortable level (neither too high nor too low). Keep rooms well ventilated, especially during summer, to avoid sweating.
• Keep patient's bedroom cool and dry to reduce house dust mite growth.
• Eliminate allergenic factors such as pets, smoke (both tobacco and wood) or dust mites.
• Talk to your dietitian or doctor about keeping a food and symptom diary, if you suspect food to be a trigger.
• Avoid unflued gas heaters, kerosene and paraffin heaters, etc.
• Use cotton covers on vinyl or leather car seats and kitchen chairs/sofas to avoid itching and sweating, and house mite contact
• Avoid stuffed toys, which harbour dust mites. Dust mite allergy can cause eczema.
• Use 100 per cent cotton bedding.
• Use non-wool blankets and bedspreads. Regularly hot wash all patient's bedding.
• Change bed linen weekly.
• Avoid feather filled pillows.
• Use anti-dust mite covers on mattresses, pillows and duvets.
• Air mattresses, pillows and other bedding in direct sunlight regularly.
• Vacuum mattresses regularly for dust mites or use dust mite covers on pillows and mattress. Use a vacuum cleaner with a HEPA filter to reduce dust disturbance.
• Damp dust to reduce dust particles in air.
• Keep furniture and fittings simple and easy to clean.
• Avoid contact with sandpits (sand at the beach is cleaner).
• Avoid contact with some grasses, pollen and moulds.
• Avoid contact with paints, resins, varnishes, etc, as these can aggravate eczema.
• Avoid aerosol sprays eg insecticides, air fresheners and polishes.

Baths

Baths are important. Sit in a tepid (never hot) bath for 20 minutes at least once a day.
Use an emollient in the bath (emollient, antiseptic, anti-inflammatory and cleanser). You do not use soap with these products.

Alternatively use an emulsifying cream as a soap substitute. If you do use soap, use a mild soap.

Within three minutes after the bath, lubricate the skin to lock in the moisture. You may do this while still wet or after gently towel-drying the skin. You may find it helpful to use a kitchen timer to teach yourself how quickly three minutes passes.

Moisturise with emollient creams, emulsifying ointment or vaseline. Vegetable shortening may be an inexpensive alternative.

Avoid using lotions. They usually contain high levels of water and possibly alcohol, which will dry the skin out more.

Use 100 per cent cotton soft towels. Pat the skin dry.

Do not use bubble baths or strong soaps.

Make baths fun by filling a paddling pool and allowing your child to bathe outdoors.

Tar shampoos help remove the flaking skin on the scalp. Ask your doctor if you should try one. If you don't need a tar shampoo, be sure to use a mild soap or shampoo.
Shampoos and conditioners containing yeast and/or wheat protein are common causes of irritation.

NB. If using a new cream, ointment or soap, try some on a small patch of skin before applying it to the entire body to be sure it will not cause a reaction. Talk to your doctor or pharmacist about whether a particular product may be suitable for your skin or not. You may need to try more than one product before finding one which does not cause further irritation.

Laundry

Use a gentle laundry product when washing clothes and linens. Be sure to rinse everything at least twice to remove all traces of soap or detergent.

Avoid bleach or fabric softeners.

Wash all new clothes and bed sheets before using them to remove the chemicals introduced in the manufacturing process.

Hot wash all bedding at greater than 55 degrees Celsius to eradicate mites and their faeces.

Swimming

Both chlorinated swimming pools and sea water dry out the skin and make it itchy. Wash under fresh water or have shower, pat dry and apply a moisturising/emollient cream.

Acknowledgements: Food Allergy Network USA, Dr A. Liang, 
Dr R. Ameratunga, Dr V. St A. Crump, Dr D. Greig, Dr Brian Broome, 
Prof. Robert A. Wood and the Australasian Society of Clinical Immunology
and Allergy.