Ask the expert: Psoriasis

Q:

Sorry, there are no polls available at the moment.My 15-year-old grandson has just been diagnosed with the skin condition psoriasis.

The doctor does not know what’s caused it, but has prescribed vitamin D and a cream to be put on all over the body.
I was wondering if there was anything else that might help ease the condition, especially the irritation.

Ms Betty Lindsey,  Billericay, Essex.

A:

Psoriasis affects 2.5 million people and usually strikes between the ages of 15 and 30, or after the age of 40

Your grandson has my sympathy, as psoriasis can be a frustrating condition, and its unsightly appearance can knock self-confidence – a precious commodity in the teenage years.

The diagnosis is made based on the symptoms, such as itching, and the physical appearance: the condition produces raised patches of red skin which are covered in thick silvery scales.

The cause of the condition is not fully known, as your grandson was informed, but it’s thought to be due to a malfunction in the process that produces new skin cells. Too many are produced and they then build up in clumps on the skin.

We know that there is a genetic link; 40 per cent of patients have a parent or sibling who also has the disease.

It can also be triggered by infection or stress; and lifestyle factors such as smoking or obesity are known to make it worse.

A plaque may be from 1cm (the size of an aspirin) to over 10cm (the size of an apple) in size. Sometimes they itch.

The severity may wax and wane: at least a quarter of people just get better, and overall health is not affected.

Plaque psoriasis responds well to creams rubbed into the skin. Medication taken orally is reserved for more severe disease affecting more than 10 per cent of the body surface (the palm of the hand is about 1 per cent of the surface).

Most often in milder cases the treatment is with steroid (cortisone) cream and emollients, such as E45 cream, as this combination is good at alleviating the inflammation and any itching.

Substances derived from vitamin D may be used, though it is unclear how they work. Preparations are also available that are a combination of vitamin D and steroid, and these can produce considerable improvement within weeks.

However the key to treatment is for the doctor to explain carefully the nature of psoriasis, making clear that this is a potentially long term (chronic) condition. The patient must be reassured that the condition can be alleviated, though rapid complete cure is unlikely.

The doctor needs to follow the patient carefully, as over time, different approaches may need to be employed, including ultraviolet light, which works by reducing skin cell division and inflammation; or laser treatment, which has a similar mechanism of action as ultraviolet light – but with a faster response.

There may also be a need to try different types of oral medication, such as methotrexate, which reduces skin cell production by affecting the DNA in these cells.

It’s important your grandson is confident about the help he’s being given – so I’d recommend he ask his GP to refer him to a dermatologist specialising in this condition, which could lead to an improvement within weeks.