Psoriasis
Psoriasis occurs when skin cells are replaced more quickly than usual. It's not known exactly why this happens, butresearch suggestsit's caused bya problem with the immune system.
Your body produces new skin cells in the deepest layer of skin. These skin cells gradually move up through the layers of skin until they reach the outermost level. Then they die and flake off. This whole process normally takes around three to four weeks.
In people with psoriasis, this process only takes about threeto seven days. As a result, cells that aren't fully mature build up rapidly on the surface of the skin, causing red, flaky, crusty patches covered with silvery scales.
Your immune system is your body's defence against disease and it helps fight infection. One of the main types of cell used by the immune system is called a T-cell.
T-cells normally travel through the body to detect and fight invading germs such as bacteria, but in people with psoriasis they start to attack healthy skin cells by mistake. This causes the deepest layer of skin to produce new skin cells more quickly than usual, which in turn triggers the immune system to produce more T-cells.
It's not known what exactly causes this problem with the immune system, although certain genes and environmental triggers mayplay a role.
Psoriasis runs in families. One in three people with psoriasis has a close relative with the condition.
However, the exact role that genetics plays in causing psoriasis is unclear. Research studies have shown many different genes are linked to the development of psoriasis. It's likely that different combinations of genes may make people more vulnerable to the condition. However, having these genes doesn't necessarily mean you'll develop it.
Many people's psoriasis symptoms start or become worse because of a certain event, known as a trigger. Knowing your triggers mayhelp you toavoid a flare-up. Common triggers include:
Psoriasis isn't contagious, so it can't be spread from person to person.
Psoriasis is a skin condition that causes red, flaky, crusty patches of skin covered with silvery scales.
Psoriasis typically causes patches of skin that are dry, red and covered in silver scales. Some people find their psoriasis causes itching or soreness.
Psoriasis occurs when skin cells are replaced more quickly than usual. This may caused by a problem with the immune system, perhaps due to genetics or environmental triggers.
Treatment for psoriasis usually helps to keep the condition under control and most people can be treated by their GP.
Although psoriasis is just a minor irritation for some people, it can have a significant impact on quality of life for those more severely affected.
Ray, 69, has been chairman of The Psoriasis Association for the last 33 years. He's lived with psoriasis since he was 14 and continues to treat it with coal-tar medication.