Backgrounder

Q1. What is the skin barrier?
The skin barrier is the first line of defence that we have against the outer environment. It keeps unwanted things from entering the body, including germs which may trigger immune reactions in the body.

Q2. What are IgE antibodies?
IgE antibodies are a subset of what we call antibodies, which are proteins in our blood that help recognise and defend our body from external things. They work to fight bacteria and also recognise things such as food and dust mites and contribute to immune reactions against them.

Q3. What is the “brick wall analogy” in relation to the skin barrier?
The skin is structured like a brick wall, so it has cells and proteins between the cells similar to bricks and mortar. Both of these structures need to be kept healthy and intact so that they can keep things out which need to stay out from the body. So if you have parts of these - either the cells or the proteins in between them - breaking down, they will no longer be able to do this job.

Q4.When was it realised that the skin barrier and not raised IgE levels was the major reason for eczema?
A groundbreaking paper was published this year showing that the breakdown of the barrier of the skin is one of the very early events which leads to a cascade of many others including those of the internal immune system which causes eczema to develop and progress.

Q5. Why is the new evidence on the skin barrier so groundbreaking?
For many years we’ve primarily focused on dealing with the immune system to keep eczema under control. We’ve known about moisturisers but considered them to be secondary in the management of eczema. However, we have only just realised that the barrier of the skin plays a much more complex and important role in eczema and that the way we were dealing with the immune system and overlooking the barrier, was almost like throwing the baby out with the bath water.

Q6. What is the role of the skin barrier in mild to moderate eczema?
The skin barrier is particularly important in the management of mild to moderate eczema. There are regulators in the skin called ‘proteases’ which help to keep it intact, or in one piece. Anything that throws these regulators out of balance can potentially kick-start a whole chain of inflammatory events, which can rapidly cause the eczema to become severe.

Q7. What happens in a defective skin barrier in terms of eczema?
In eczema the skin barrier is often not totally intact, which means that a number of things including irritants such as water and soaps as well as allergens can actually enter the body and provoke an attack on the immune system.

Q8. What contributes to skin barrier breakdown?
The skin barrier can break down due to irritants directly affecting the skin, or the breakdown can be mediated by factors that the skin itself produces. If those factors are kept well balanced, then this should provide a good, healthy skin. However if something increases these factors, then the skin barrier will be damaged.

Q9. Can you explain the role of genetic defects in skin barrier breakdown?
The skin barrier is affected by both environmental and genetic factors. We know that there are possibly four or five major genes which are involved in regulating the eczema process, some of which affect the immune system and others the skin barrier. These factors work partly hand in hand with the environment to keep the skin intact or to destroy it, allowing eczema to progress.

Q10. Can you explain the role of environmental irritants on skin barrier breakdown?
Environmental irritants can directly break down the skin chemically. For instance, over-exposure to soap and water can be like rubbing raw skin into sand. On the other hand, environmental irritants can actually enhance the body’s own break down mechanisms. For example, by altering the pH of the skin, you can actually make the body’s apparatus which breaks down the skin, work over-time.

Q11. Can you explain the role of allergens on skin barrier breakdown?
Golden staph and dust mites themselves produce a number of chemicals which directly breakdown the skin. They also stimulate the immune system to do the same thing.

Q12. Can you explain the role of steroid creams on skin barrier breakdown and when they should be used in the eczema cycle?
With severe eczema, there is a large volume of different chemicals that are released for which application of steroid creams can prove very useful in suppressing these, somewhat like a blanket smothering a fire. On the other hand, when eczema is very mild, there is a very delicate house-keeping system in the skin that keeps the barrier just right. In this case, the steroids can actually interfere with the house keepers and cause the skin to breakdown even more.

Q13. Can you explain the role of non-steroidal creams on skin barrier breakdown and when they should be used in the eczema cycle?
The skin itself has a beautiful but very delicate house-keeping system that works to keep it intact (in one piece). When the skin is mildly to moderately inflamed, the house-keepers need to work hard to keep it intact. The beauty of the non-steroid creams, as shown in the latest findings, is that they do not interfere with these house-keepers at all. Special properties of these creams allow them to work effectively to reduce inflammation in order to clear the eczema and remove the heat, redness and itchiness without damaging the skin barrier in any way.

Q14. Is the role of the skin barrier as important in adults as it is in children?
The skin barrier is important in both adults and children. Even adults have areas where the skin is very thin and in those areas if you affect that barrier just a little bit, such as the eyelid, you can cause a lot of damage.

Q15. Does the skin barrier play a role in severe eczema?
The skin barrier is also very important in severe eczema. It is usually severely damaged and consequently, irritants and allergens which shouldn’t be entering the skin can penetrate through and worsen the process.

Q16. What do these new findings into the skin barrier mean for the management of eczema?
These new findings on the role of the skin barrier and non-steroid creams are of great significance to the management of eczema. Steroids still have a role to play, especially in controlling severe eczema. However, with mild and moderate eczema, we now have a beautiful alternative which can help prevent flares and effectively control, without in any way affecting, the barrier of the skin. This means that we may now use less of the stronger medications to control eczema flares and experience fewer problems, even with more prolonged use. We avoid skin thinning, steroid dependency, drug ineffectiveness and flare-ups very satisfactory control of eczema.

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To organise an interview with Dr John Su, please contact Kirsten Bruce or Ruby Archis from viva! communications on 02 9884 9011 or 0401 717 566 / 0413 834 906.