The medical condition of the week this week is something close to my heart as it is a condition my Nan has dealt with for many years. Psoriasis is an immune condition which causes the skin replacement process in the body to speed up. This causes the skin cells to build up in raised patches known as “plaques” on the skin, which often look red and flaky, and are often itchy.
Psoriasis effect between 2% and 3% of the population in the UK and affects both genders equally.
Psoriasis is often caused by a certain effect or “trigger” which causes the immune system to produce new skin cells more quickly. Common triggers include an injury to the skin such as sunburn or an insect bite (known as the Koebner response); drinking large amounts of alcohol or smoking; being under a lot of stress; hormonal changes such as those during puberty and the menopause; infections; other immune disorders; or certain medications including antimalarial medicines, anti-inflammatory medicines and beta blockers. It is in fact a reaction to penicillin when she was a child which my Nan believes triggered the start of her Psoriasis. It is also thought, like with many immune conditions that there is a genetic link with Psoriasis, however the exact role which genetics plays in the development in the condition is still unclear.
There are many different types of psoriasis, most of which are classified by the area of skin which is effected by psoriasis and the severity. The most common type of psoriasis is chronic plaque psoriasis, which is thought to account for about 90% of people with in condition. With chronic plaque psoriasis the plaques are normally pink or red with overlaying flaky silvery-white scales, and there is normally a sharp boarder between the edge of the plaque and the “normal” skin. The severity of the rash is very different for each person can also vary dependant on the time of year and if events have triggered a “flare-up” of the condition. The most common areas affected by the rash are the skin of the elbows, knees, and lowers back. There are two variations of chronic plaque psoriasis; scalp psoriasis and flexural psoriasis. Scalp psoriasis, as the name suggests, affects the scalp, and often may be visible on the forehead and behind the ears. Some people with scalp psoriasis feel very little discomfort, although in some severe cases is can cause hair loss, although this is usually only temporary. Flexural psoriasis, occurring in the creases of the skin known as flexures, this includes the armpit, groin, under the breasts and in skin folds. The plaques with flexural psoriasis, although are red and inflamed, will often be smooth to the tough and not have the rough scaling as which other types of psoriasis.
Pustular psoriasis is a much rarer form of the psoriasis and causes pus-filled blisters, known as pustules, to appear on the skin. The “pus” consitis of white blood cells and is not a sign of infection, and is not in any way contagious. Generalised pustslar psoriasis, or von Zumbusch psoriasis, often causes the development of the pustules in cycles, in which they will develop quickly and over a large area of the skin. There can often be associated symptoms with these cycles such as fever, chills, weight loss and fatigue. Palmoplantar pustular psoriasis affects the palm of the hands and the soles of the feet. Due to its nature this type of psoriasis can often be quite painful and the skin is usually very red and can crack. However like with the generalised type it often occur in cycles every few days or weeks.
About 50% of people with psoriasis will also have fingernail psoriasis. With this type of psoriasis small indentations appear in the nails and they can often become loose of the nail bed, a condition known as onycholysis and may change colour around the nail bed to a yellow/brown colour, giving the impression of oil droplets.
Guttate psoriasis often develops following a sore throat caused by a bacterium and causes lots of small round plaques which often develop across the torso, back, arms and legs. This type of psoriasis is most common in children, teenagers and young adults and although it often develop very quickly, guttate psoriasis often lasts a few weeks to a few months and foes away on its own. Up to half of people will never have another attack, however, some will go on to develop other forms of psoriasis.
Erythrodermic psoriasis is a rare form of psoriasis and affects nearly all of the skin causing widespread redness and intensive itching and burning of the skin. Although it is rare, erthrodermic psoriasis can cause the body to loose proteins and fluid and so requires urgent admission to hospital in order to stabilise the fluid and protein loss to prevent dehydration.
Psoriasis can be treated in a number of ways including topical treatments, creams and ointments, which are applied to the skin and are often used on mild psoriasis. These include; topical corticosteroids – these reduce inflammation and slow down the production of skin cells and reduce the symptoms of itching; vitamin D analogues – these work in the same way as topical corticosteroids and are often used alongside or instead of them; calcineurin inhibitors – these reduce the activity of the immune system and help to reduce inflation, they are often used to treat psoriasis in sensitive areas such as the scalp; coal tar- the exact way in which it work is unknown however in reduces scales, inflation and itchiness, and is often used which other topical treatments have been ineffective.
Other treatment include the use of phototherapy, the use of natural and artificial light to treat psoriasis. This includes; UVB phototherapy, which uses light to slow down the production of skin cells; and Psortalen plus ultraviolet A (PUVA), a combination of a psoralen tablet or cream and the ultraviolet A light which penetrates more deeply than ultraviolet B. Phototherapy, is often used is topical treatment is not successful, and often requires regular session of treatment. Systemic treatments are medication which are used as a last resort for psoriasis as they have potentially serious side effects. However they include; ciclosproin – an immunosuppressant; acitretin – reduces the production of skin cells; and etanercept, adalimumab, infliximab and ustekinumab injections.
Overall, although like any chronic disease sufferer will have both good and bad days. Research into the causes of psoriasis is constantly going on, and so are developments within treatment. Although complications of the condition such as psoriatic arthritis (a form of arthritis caused by psoriasis) can occur, with good management of the condition and treatment plans most sufferers are still able to lead normal, healthy lives.
Sources:
http://www.nhs.uk/Conditions/Psoriasis/Pages/Introduction.aspx
http://www.patient.co.uk/health/psoriasis
https://www.psoriasis-association.org.uk/pages/view/about-psoriasis
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