Psoriasis

What is psoriasis?

Psoriasis is a condition which leaves the skin with red, crusty and flakey patches and silvery scales. These patches can appear anywhere on the body but are typically found on the knees, elbows, lower back and scalp.

In the UK, psoriasis affects around 2% of the population and symptoms can start at any time in your life. Psoriasis is not contagious so cannot be spread through bodily contact.

What causes psoriasis?

Psoriasis occurs when the skin replaces cells fast than usual. The exact cause is not clear, however, research suggests it is related to a problem with the immune system. Everybody’s skin cells are replaced constantly. New cells are produced in the deepest layer of skin, moving up until they are eventually shed. This process normally takes around 4 weeks to complete. For those who have psoriasis, this process happens over 3 to 7 days. The immune system helps your body fight against infection and disease. T-cells are part of its defence toolkit which is mobilised to attack invading germs, such as bacteria. With psoriasis, T-cells mistakenly attack healthy skin cells which encourage the production of replacements to speed up.

It is not known what causes this problem with the immune system although it is thought to be triggered by genetic factors as 1 in 3 psoriasis sufferers have a close family relative with the condition. Environmental factors are also thought to play a role in triggering psoriasis.

‘Triggers’ are events which can start psoriasis or contribute to a flare-up. Common triggers include:^[1]

What are the symptoms of psoriasis?

The newly formed cells build up rapidly on the surface of the skin which results in patches of red, crusty, flakey skin with a scale-like quality that may also be itchy and sore.

There are several different types of psoriasis and people tend to experience only one at a time. One type of psoriasis may turn into another if your symptoms get worse.

Common forms of psoriasis include:^[2]

• Plaque Psoriasis (Psoriasis Vulgaris) 
• Scalp Psoriasis 
• Nail Psoriasis 
• Guttate Psoriasis 
• Inverse (Flexural) Psoriasis 
• Generalised Pustular Psoriasis, also known as von Zum Busch Psoriasis
• Palmoplantar Pustular Psoriasis 
• Acropustulosis 
• Erythrodermic Psoriasis

What is Plaque Psoriasis?

The most common form, Plaque Psoriasis accounts for about 80% of cases. It manifests itself in dry, red skin lesions, known as plaques. These are covered in silver scales typically found on the elbows, scalp and lower back. Joints may crack and bleed in extreme cases.

What is Scalp Psoriasis?

Scalp Psoriasis can occur on parts of or the whole scalp. This causes red patches of skin covered in thick silvery-white scales. Scalp Psoriasis can be extremely itchy for some and in extreme cases may cause temporary loss of hair

What is Nail Psoriasis?

This affects the nails of about half the people with psoriasis already. This is because Psoriasis can cause your nails to develop tiny dents or pits. These become discoloured or grow abnormally. Nails can often become loose and separate from your nail bed and in severe cases, can crumble.

What is Guttate Psoriasis?

Guttate Psoriasis can cause small (less than 1cm or 1/3 inch) drop-shaped sores on your chest, arms, legs and scalp. It can disappear completely after a few weeks, but some may develop plaque psoriasis. This type of psoriasis sometimes occurs after a streptococcal throat infection and is more common among children and teenagers.

What is Inverse (Flexural) Psoriasis?

Inverse Psoriasis can affect the folds or creases in your skin, such as the groin, armpits, between the buttocks and under the breasts. It can cause large, smooth red patches in some or all of these areas. Symptoms are made worse by friction and sweating, so it can be particularly uncomfortable in hot weather.

What is Generalised Pustular Psoriasis?

Generalised Plustlar Psoriassis causes pustules on a wide area of skin, which develop very quickly. The pus consists of white blood cells and is not a sign of infection. Pustules may reappear every few days or weeks in cycles. During the start of these cycles, von Zumbusch psoriasis can cause fever, chills, weight loss and fatigue.

What is Palmoplantar Pustular Psoriasis?

Causes pustules to appear on the palms of your hands and the soles of your feet. The pustules gradually develop into circular brown, scaly spots, which then peel off. Pustules may reappear every few days or weeks.

What is Acropustulosis? 

This causes pustules to appear on your fingers and toes. The pustules then burst, leaving bright red areas that may ooze or become scaly. These may lead to painful nail deformities.

What is Erythrodermic Psoriasis? 

Erythrodermic psoriasis is a rare form of psoriasis that affects nearly all the skin on the body. This can cause intense itching or burning. Erythrodermic psoriasis may cause your body to lose proteins and fluid, leading to further problems such as infection, dehydration, heart failure, hypothermia and malnutrition.

How do you treat psoriasis?

In the first instance, contact your GP if you think you have psoriasis. If your symptoms are particularly severe, they may refer you to a dermatologist for further treatment.

The treatment options vary depending on the type of psoriasis you have and the severity of its symptoms. Complete emollient therapy is a well-established approach which treats psoriasis by using a combination of different creams, ointments and oils throughout the day.

There are topical treatments which are creams and ointments applied to the skin which provide relief. Exorex lotion contains coal tar and your skin should begin to show improvements within a few weeks.

For scalp psoriasis, tar-based shampoos are commonly used such as Capasal, Alphosyl, Neutrogena T-Gel.