What is Psoriasis ?
Psoriasis (psoriasis vulgaris) is a chronic autoimmune disorder, characterized by an accelerated division (proliferation) and decreased maturation (differentiation) of keratinocytes in the epidermis. Because the cells are not normally ripen flaking is also disrupted, causing takes place locally strong exfoliation of skin scales on the affected area. Although psoriasis is particularly evident in the skin, it is not primarily a skin problem, but a disorder of the immune system (autoimmune disease).
Periods of remission of the symptoms are often interspersed with periods in which the disease worsens. The affected skin of a psoriasis patient renews itself in 6 to 7 days; in non-patients, this is 26 to 27 days. However, the structure of the self-renewing skin layers deviates significantly from normal.
Psoriasis is not contagious. Approximately 2% of the world have the condition, only South American Indians it is much rarer. The highest incidence is found in Scandinavia and Northern Europe (3%). Often exists in people with psoriasis have a genetic predisposition for the occurrence of accelerated skin sharing. This investigation focuses on loci on chromosomes 17q, 4q, 1q, 6p21.3 and Psors 1 gene.
The name psoriasis comes from the Greek "psora" which means itch or rash. The first clear description of this syndrome dates from 1801. Men and women are equally often affected by this condition, and 75% of patients showing the first symptoms before the age of 40.
Types of Psoriasis
There are several types of psoriasis, of which the most abundant (psoriasis vulgaris, psoriasis, and also referred to as plaque) the 'ordinary psoriasis' is. Typical of most forms of psoriasis are white flakes of skin on skin redness. These places are called plaques. They exhibit the following four characteristics:
- The plaques are clearly defined, the transition to the unaffected skin is sharply defined
- The surface is not well interconnected silver-white scales
- Under the skin flakes has a shiny, homogenous redness
- If one is scratching such a place, let the dander on a wax-like fashion loose which appear small blood droplets on the skin red. This is the so-called sign of Auspitz, and diagnostic important because fretting other conditions such as eczema, can rule.
Changes to the nails also occur frequently. The nails of the hands in 50 per cent, and the toenails in 35 per cent of the cases. Three types of changes may occur:
- The formation of small pits in the nail surface
- A yellowish discoloration under the nail
- By damaging keratin-containing layers in the nail, it gets a yellowish color and is "friable".
Other types of psoriasis are:
- Guttate psoriasis - consists of 1-5 mm large spots on the trunk, and also on the upper arms and -benen. This is an acute shape, which can occur in children and adolescents. Usually one sustained in the two weeks before the appearance of the nodules a streptococcal infection in the form of a throat infection. Mostly psoriasis guttata disappears after 3 to 4 months itself. Approximately one third of patients develop plaques later classical variant.
- In psoriasis-erythrodermia total body surface area is affected. It is a severe form of psoriasis, occurring in about two per cent of the cases. Redness of the skin is the most striking feature. All other symptoms of psoriasis are present, but the scaling and plaque formation are usually less prominent. Hypothermia, hypoalbuminemia and heart failure may occur. The chance of life-threatening situations, is present. It can occur after a non-tolerated treatment of the skin with dithranol or UVB, and can then be seen as a generalized Koebner reaction. It can also be caused by certain other medications, atopic dermatitis (eczema), and cutaneous T-cell lymphoma.
- Pustular psoriasis is an acute form of psoriasis where the psoriasis consist of 2-3 mm vesicles with pus in the surrounding inflamed skin, usually on the trunk, the nail beds, palms and soles. She is accompanied by fever that lasts several days. The blistering and fever usually occur in waves. If the nails are affected, in patients with a long-lasting psoriasis pustular, atrophy of the fingers may occur. Furthermore, there are two variants of pustular psoriasis. Sometimes pustular psoriasis is regarded as a stand-standing illness, not directly covered by the psoriasis range. It is much more common in smokers.
Psoriasis palmaris and plantaris (psoriasis spots on the palms and soles), inverse psoriasis (fires just in skin folds such as the armpits and groin), psoriasis unguum (nail psoriasis) and scalp psoriasis (psoriasis on the scalp) are no separate types of psoriasis but give the place where the psoriasis (vulgaris) occurs.
What Causes Psoriasis ?
The exact cause of psoriasis is not known, although there are on the disease mechanism does exist an increasing insight.
Immunological Aspects
Initially, it was assumed that psoriasis disease was to rapidly proliferating cells (keratinocytes) in the epidermis. Nowadays, psoriasis is considered to be a disease which is caused by immunological factors (autoimmune disease), in which genetic factors also play an important role. The major evidence for this is the finding that the administration of a number of biologicals which act on immune factors, such as CTLA4Ig and DAB389IL-12 can influence advantageously the disease. In the plaques are located groups of T-cells and dendritic cells, which is likely to form the basis for the inflammatory reactions that occur such as in psoriasis. The plaques are the result of the interaction between different cell types: keratinocytes (the most common cell in the upper layer of the skin), and T-cells and dendritic cells. If one has a genetic predisposition to psoriasis, the keratinocytes may release substances that affect the T-cells and dendritic cells, and vice versa. Consequence: overactive keratinocytes cause flaking, the dendritic cells give Tumor Necrosis Factor-alpha and interferon alpha-off, which contribute to the inflammation. This set of interactions leads to the clinical picture as one sees in psoriasis.
Genetic factors
Genetic factors play a role in the predisposition to psoriasis, but are not fully determined. The precise mode of inheritance is still unknown. Approximately 30 percent of patients have a parent or child with the disorder. If both parents and the child have the disease, is the chance that another child psoriasis will get 50 percent; if a child has the disease but not the parents, the chance for another child drops to 8 percent. When one half of an identical twin has psoriasis varies the probability that the other half of this condition also has 65-72%, although a research in Australia showed a lower percentage of 35%. This means that other factors (from the environment) also play a role in whether or not occurrence of psoriasis.
About 10 to 20 regions are associated with psoriasis on different chromosomes, including PSORS1 up to and including PSORS9. PSORS1 is of great importance, because this may be responsible for 35-50 percent of heredity. However, only a small number of genes have been identified: HLA-C, SLC9A3R1, NAT9 and SLC12A8.
Recently, the role of the number of copies of genes which demonstrated encoding beta-defensins. Beta-defensins possess anti-bacterial properties, but in this case more important, also inflammation stimulating properties. The number of copies is set between 2-12. Most people have modal 4. Compared with these people, the risk of getting psoriasis increases by more than a factor of two, if one has 6 or more copies.
Other
Also known are a number of factors that psoriasis can be created or existing psoriasis may worsen. They are also called "triggers". One should, however, already have a genetic predisposition for the development of psoriasis, because not everyone by these triggers develop the disease.
Major triggers:
- Injury
- Infections
- Drugs
- beer. More than five beers per week already give a doubling of the probability of psoriasis. Other alcoholic beverages increase no chance. Probably, therefore, substances other than the alcohol in beer responsible for this effect. According to the researchers is to make this possible with the large amount of gluten in beer.
There are indications that diet plays a role in the flare of psoriasis. Regular fasting, vegetarianism and a diet rich in fish fatty acids (EPA and DHA) are associated with an improvement in psoriasis.
Many psoriasis patients are allergic to gluten. These patients exhibit a significant improvement in the symptoms to be followed by a gluten-free diet for three months. However, the potential impact of gluten on psoriasis is still under discussion.
Psoriasis Treatment
Topical creams. For decades, the majority of psoriasis patients treated with a topical medication. There are some liniments and ointments that have a positive impact, often with corticosteroids (eg, betamethasone dipropionate or clobetasol propionate). Also sometimes ointments containing salicylic acid or vitamin D related substances used as calcipotriol and calcitriol. The tar products are largely obsolete (outdated), mainly because they smell bad and the treatment is very cumbersome. In addition, there are a number of radical treatments that can be used as local resources are insufficient effect.
Hyperbaric oxygen therapy. Hyperbaric oxygen therapy may be effective in treating psoriasis.
Laser light, an effective therapy is the treatment of the places with a pulsed dye laser. In addition to the blood vessels that supply the destroyed psoriasis spot of nutrients, and the spot disappears. Particularly advantageous in this respect is that the place without further treatment for a relatively long stays away and this treatment has no serious side effects.
UV treatment. Another frequently applied treatment is light therapy: A traditional therapy exposure to lamps which emit mainly UV-A light (PUVA), in combination with the application of psoralens which sensitize the skin to UVA light. This treatment experienced quite a few side effects. A more modern variant is the use of narrow-band UV-B light (311 nm), in which no means have to be applied. In both cases, there is, in view of the use of UV light, an increased risk of skin cancer.
Exposure alone (intensive) sunlight (which greatly enhances the vitamin D status) without psoraleenbehandeling also appears to be sufficient to reduce the symptoms greatly.
Systemic drugs. When serious and debilitating cases, often in combination with arthritis are sometimes given so-called "systemic" treatments (tablets), based on methotrexate or cyclosporine. These agents can have severe side effects and are used only under close physician supervision.
Another scientifically accepted therapy is the use of fumaric acid esters. Mostly used for this purpose is a drug with a mixture of different mono-ethylfumaraten plus dimethyl fumarate. Further, the patient to adhere to a diet which aims to keep the content of pyruvic acid as low as possible. To this end, for example spices, wine and peels to be avoided. Energy (citric acid cycle) in the body cells in psoriasis would be disturbed and fumaric acid (combined with pyruvic acid limitation) the citric acid cycle would again boost. The operation of these fumarates would be based on inhibition of NF-kappa B, and induction of apoptosis of T-cells. Side effects include abdominal cramps, diarrhea, nausea, hot flashes and fatigue.
A fairly costly forms of treatment biologicals. Within the group of biologicals is a distinction between the so-called TNF inhibitor and T-celmodulatoren. Given the price, strict criteria applied before one qualifies for such treatment into account. Given the nature of these drugs is the risk of side effects and their severity, not what you'd call good. In some of these agents psoriasis returns soon after the discontinuation of treatment back.
Alternative Treatment of Psoriasis
As with all chronic diseases, and changing existing alternative methods are also applied in psoriasis:
- Many patients undergoing treatment at the Dead Sea in Israel (Ein Bokek) or Jordan. The influence of the salt water and the sunlight passes for many patients, a reduction in symptoms.
- In several spas in the northern and central Middle East, mainly in Turkey, Syria, Iraq and Iran can psoriasis patients to be treated by two kinds of fish (Biopeeling) (Garra rufa and Cyprinion macrostomus), which eat the scabs. This so-called ichthyotherapie can now also be subjected to various other places in the world. According to a pilot study seems ichthyotherapie combination of UV treatment with a valuable method of treatment, but further research is needed before any firm conclusions can be drawn.
Cure is not possible
There is no therapy that can cure someone, it is in all cases symptoms. However, there are significant differences in remission times, ie the time a patient remains free of spots after the conclusion of therapy and the side effects.