What is psoriasis?

Psoriasis is a hereditary skin disease that affects the way that skin cells grow and replace themselves. Psoriasis results in patches of sore, itchy, red skin that is covered in silvery scales. These generally occur around the elbows, knees and scalp, although the site of the psoriasis varies depending on the type of disease.

Psoriasis is an auto-immune disease, in which the body’s own defences attack healthy tissues. In psoriasis, T-cells in the blood ,which are normally part of your body's defence system start, attack the skin, causing the immune system to create more skin cells. This rapidly speeds up the skin lifecycle from around 28 days to just 5 or 6 days, creating a build-up of dead cells on the skin’s surface resulting in the typical scaly patches. Psoriasis affects around 2 % of people, occurring in cycles of flare ups.

Types of psoriasis

There are several types of psoriasis:

  • Plaque psoriasis accounts for 80 % of psoriasis cases, causing red, scaly lumps on the elbows, knees and scalp.
  • Guttate psoriasis can occur after a throat infection caused by Streptococcus bacteria. This causes small sores on the chest, scalp, arms and legs.
  • Scalp psoriasis is an extremely itchy form of psoriasis that can cover the whole scalp and can lead to hair loss in severe cases.
  • Flexural psoriasis occurs in folds of skin, such as the groin or below the breasts, creating smooth red patches of sore, itchy skin.

Other, rarer forms of psoriasis include pustular psoriasis, erythrodermic psoriasis and nail psoriasis.

At The London Clinic, our dermatologists can diagnose all types of psoriasis and can recommend first line and follow-up treatments to bring the condition under control.