Atopic eczema is a very itchy, dry inflammatory skin condition. In healthy skin the skin barrier (top layer of the skin)...
Skin without eczema
In skin where there is no eczema or dry skin, the surface of the skin – also called the skin barrier – is intact. This means that there are no breaks in the skin.
This acts as a barrier to prevent bacteria, allergens or irritants getting through the skin layer. The cells of the skin bind together, like a well cemented brick wall with no gaps, and there is no excess loss of moisture from the skin. The skin barrier is also protected or lubricated by natural oils in the skin.
Skin with eczema
In skin with eczema, the skin is dry and the skin barrier is weakened or broken. This weakened or broken skin barrier means that bacteria, allergens and irritants can get deeper into the skin layers. These can cause inflammation and infection and increase the risk of infection and allergic sensitisation.
In people with Eczema, the corneocytes, the building blocks of the skin, are an irregular shape and therefore do not bind together very well (like an old brick wall with gaps). This means moisture can escape and bacteria, allergens and irritants can travel deeper into the skin layers causing inflammation and itch.
The skin producing less natural oil can also contribute to the development of eczema, causing dry and itchy skin and a genetic mutation or fault on the filigrin gene.
In atopic eczema, there is an immune response where the body creates a reaction to a usually harmless substances such as pollen or animal saliva or fur. These irritants and allergens enter the body through the broken skin. They make contact with cells in the immune system and these cells mistake the irritants and allergens for harmful invaders (bacteria). This causes the immune cells to overreact and mount an attack.
The immune cells in the blood then produce lots of chemicals, including cytokines and histamine, to attack the irritant or allergen. This immune response is designed to prevent it causing harm to the body. However, in protecting itself, the immune system causes an inflammatory reaction. Which in eczema, results in the familiar redness, swelling, itch and rash.
Although this immune response can sometimes happen quickly within minutes, often in eczema, it can take hours, or even days to appear on the skin. This is why it can be so difficult to detect triggers that worsen your eczema.
Chronic or longstanding eczema can be very difficult to treat. The overreaction in the immune system isn’t switched off and the immune system keeps on producing chemical messengers to try to protect itself, even long after triggers and allergens have been removed from the environment.
This can lead to temporary skin changes, such as thickening of the skin, called licenification, and patches of the skin darkening or lightening, called inflammatory pigmentation. These changes usually settle once the inflammation has calmed down, but can take months to resolve.
Treatment for atopic eczema using biologic therapies
Biologic therapies work by blocking or preventing the chemical mediators in the immune system from being able to produce an allergic response and cause inflammation. It does this by targeting specific chemical mediators (messengers) called cytokines. Cytokines help to regulate the immune system. Cytokines produce a group of chemical messengers called interleukins (IL), interleukins are useful in helping the body fight bacteria and viruses, but in allergic disease they can overproduce and cause the inflammation that leads to chronic eczema. Biologics work by inhibiting or blocking these interleukins, this stops them from reproducing and sending signals to the rest of the body, this reduces the inflammatory response which in turn reduces the symptoms of eczema such as itch and redness.
There are currently two types of biologic therapies that are showing promising results in the treatment of atopic eczema. These are Biologic therapy – Monoclonal antibodies (Mabs) And JAK inhibiters (Janus kinase inhibiter) also known as disease modifying anti rheumatic drugs (DMARDS).
A range of these medications, including injections tablets and topical cream based formulations are currently being investigated and are going through rigorous clinical testing for use for eczema (atopic dermatitis) patients to see if they can improve or control symptoms.
Scientific research into eczema and new drug therapies show promising signs for the treatment of eczema for the future. These new therapies are showing really good indications in clinical trials that they can provide effective symptom relief, significantly improve quality of life and overall reduce the impact that living with eczema has on yourself and your family.
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