Understanding Eczema: What happens to the skin in eczema?

When Miss T’s  eczema was continuously flaring, I decided to go back to my biology books and try to get my head around exactly what was happening to her skin. I’m definitely not an expert but I thought these basic facts might be useful for other eczema sufferers too.

The Basics

In simple terms, the skin consists of 3 layers – the epidermis, the dermis and the subcutaneous layers (fat).  In eczema, it is the epidermis and the dermis which are mainly affected.

The epidermis is the top layer and is made up of brick-like cells. These cells are packed tightly against each other and are held together with a ‘cement’ made mostly out of fats (lipids).  This cement is very important because it’s the skin’s defence against the outside world.  Its function is to stop environmental irritants getting in and too much moisture getting out.

The top layers of the skin.

The next layer down is the dermis.  This section contains blood vessels, oil, sweat & nerve glands.  It’s also the home of collagen and elastin which provide the skin with its strength and flexibility.  The dermis supports the epidermis by carrying messages and fluids to it so that it can respond both to the outside world and also  to what goes on inside the body.

So what happens to the skin in eczema?

In people with eczema, there tends to be a deficiency of lipids and so the brick wall loses its cement.  Cracks start to appear in the wall, allowing irritants in and moisture out.

The skin barrier is broken down.

When allergens start to enter the skin our immune systems are put on alert.  Those of us  with eczema seem to have an increased response to this threat and our immune systems can overact to substances that are normally harmless such as pollen, pet dander and dustmites.

The skin becomes inflamed and itchy and the urge to scratch is immense. The skin is then damaged further by scratching and so dreaded the itch-scratch cycle begins.

The itch-scratch cycle of eczema.

When skin becomes broken it’s also now open to infection.

This very basic understanding of the skin’s function really helped me understand why regular use of emollients are so important in eczema.  In very simple terms, we need to help restore this cement between the bricks so that irritants can’t get in and to prevent more fluid loss.