Psoriasis is an autoimmune disease of the skin of unclear origin, partly genetic. This skin disease affects 1 to 3. He then said that psoriasis is ". The disease has genetic components, autoimmune, microbiological and environmental or food (stopping the consumption of dairy products or certain other commodities are often used in the stories of people who managed to get rid of it without involving a treatment parallel).
The epidermis renews itself too quickly, in just four to six days, instead of the usual three weeks and this causes localized inflammation. Epidermal cells accumulate at the surface of the skin and form a layer of white film called dander. Perfectly harmless, yet they have the disadvantage of being unsightly. The presence of numerous leukocytes in the dermis suggested the role of the immune system.
As mentioned above, there are a small third of people with a family component to psoriasis (yet to determine the other relevant factors). The most important seems to be the PSORS1 on chromosome 6 and to be responsible for almost one third of familial psoriasis.
Flare-ups are sometimes related to stress. They can also be caused by an infectious factor (streptococcal infection, for example). Their frequency is highly variable and, in general, the trigger for the surge is not identifiable. Excessive consumption of alcohol is a factor in worsening of psoriasis.
Some medications may exacerbate psoriasis but their judgment must be discussed case by case, it can cause other hazards, especially cardiovascular. These are essentially those of the class of beta-blockers. Other molecules have been reported as potentially aggravating, however with a lower risk. These ARBs and enalapril.
On the contrary, sun exposure has a protective net. During pregnancy, a reduction of relapses with worsening by cons following it is generally observed. The mechanism invoked is that of a immuno-modulation by the high rates of progesterone and estrogen that lead to stimulation of immunity cell-dependent B but a decrease of immune activity of T lymphocytes. Progesterone is known to have immunomodulatory key role during pregnancy.
Some forms may develop following joint trauma.
Unsightly effect disabling the subject in his daily life, can be particularly unpleasant also through intense itching. When psoriasis covers the genitals, intercourse becomes more difficult because very painful.
Holders of psoriasis have a greater risk to myocardial infarction, especially since the attack is extended.
It is done in spurts with remissions (apparent recovery) more or less complete sometimes reaching several decades.
Microscopic examination of a sample of affected skin is of little use in clinical practice, clinical examination is usually obvious. This review shows an increase in the thickness of the epidermis, the presence of numerous tortuous blood vessels particularly in the dermis with infiltration of leukocytes by the latter.
In skin not reached, microscopic examination was normal.
The local treatment consists to apply a cream on the area of psoriasis. Corticosteroids have a beneficial effect on psoriasis, unfortunately the plates often return after stopping treatment. This also creates a form of desensitization, which requires larger doses over time. Moreover, the effect is not only local if you [Who?] Apply these creams over large areas. This form of treatment should be limited to acute forms or highly unattractive, for a short time and only small areas.
Calcipotriol (calcipotriene) is a derivative of vitamin D3. Normally, it is synthesized in the skin exposure to solar ultraviolet light. So here it is a substitute for the exhibition (or PUVA). The maximum amount applicable is limited because at high doses, calcipotriol becomes toxic. Tazarotene is a derivative of vitamin A available in ointment. Its tolerance is however less than calcipotriol.
Tars were once frequently used application on psoriasis but was particularly inconvenient because dirty. Dithranol is a derivative of tar. Dithranol has some efficacy, especially in combination with other treatments but it is sometimes irritating especially inconvenient (very "stain"), which limits its use.
Other treatments include salicylic acid, baths, hydrating skin. These local treatments may be optionally combined.
Sun exposure is most often a positive effect on psoriasis. However, in 10. The subject must then avoid the sun, or at least avoid being directly exposed to its rays. Phototherapy with ultraviolet B (UVB) is also recommended. In all cases, the ultra-violet therapy (A or B) must be performed under medical supervision. It results in a tolerance varies from one individual to another it is necessary not to exceed. Otherwise the patient is exposed to photodamage and low-risk-of skin cancer (squamous cell, melanoma). Particularly low risk that a patient with psoriasis has many more controls than the skin "ordinary people". which can detect at the earliest possible any incipient neoplasia. The UVB therapy is practiced with tubes providing a very specific wavelength (311-313nm). Generally three sessions per week are needed, about a few minutes per session.
Exposure to ultraviolet A (PUVA) with prior decision (oral) psoralen can help. Exposure to ultraviolet A has only limited effectiveness. The administration of psoralen tablets, shortly before the exposure to UVA, allows skin sensitization to these. Generally, three sessions per week are performed, about 5-15 minutes. PUVA is used less since the increasing use of UVB, more manageable.
Phototherapy can be combined with other therapies.
For the most severe forms of psoriasis, doctors can prescribe oral medications (pills) or injection. These are called systemic treatments because the drugs are supposed to spread throughout the body. They often have side effects, sometimes serious.
Methotrexate is an antagonist of a vitamin, folic acid. Is still used primarily in psoriatic arthritis, psoriasis exclusively in little skin. A retinoid such as acitretin, is a synthetic derivative of vitamin A may be prescribed in moderate to severe psoriasis. In women of childbearing age this treatment is teratogenic, not only for the drug but also for two years (24 months) after the last dose. Side effects are usually minor.
Psoriasis is considered close to autoimmune diseases, an immunosuppressant such as cyclosporine can sometimes produce positive effects, but its side effects are important (mainly due to the weakening of the immune system). Hydroxyurea is used more practically. Alefacept is an antibody directed against receptors of certain lymphocytes T. Has no place in the treatment of psoriasis. Infliximab is a chimeric monoclonal anti-TNF. It is administered in 2-hour infusion, at weeks 0, 2 and 6 and every 8 weeks.
Efalizumab is a monoclonal antibody directed against a certain type of leukocyte receptors with efficacy in the short and medium term. It was withdrawn from the market in early 2009. Etanercept is a TNF inhibitor that has a good efficacy but also the cutaneous articular psoriasis. Adalimumab is an anti-TNF biologic administered by subcutaneous injection every 2 weeks at a dose of 40 mg.
Other medications or treatments have been tested more or less.
Psoriasis are two periods favorable. The writer John Updike has been described by referring to his own achievement in a new collection of Problems (1979).
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