Psoriasis is a chronic skin disease characterized by the appearance of red cards, well defined, containing scales and are located in different parts of the body. Scales are thick, pearly-white, adherent to the skin and easily removable form of blades. The disease occurs in approximately 2-3% of the population.Psoriasis mainly affects certain areas of the body, including the scalp, elbows, knees and back. More rarely, armpits, palms and soles (soles) are met. In 50% of cases, psoriasis can locate the nails that peel thickens and become green.
Symptoms range from mild and reach truly harrowing events (eg, those located in the folds of joints). On the other hand, severe forms of psoriasis give rise to manifestations of emotional, affection having a negative impact on social relations, personal and emotional. Patients are often so overwhelmed by their illness that they feel isolated and depressed.
The cause of psoriasis is unknown, but one triggers include trauma, infections and certain medications. Diagnosis is based on the appearance and distribution of lesions. Treatment consists of the use of emollient creams, vitamin D, retinoids, corticosteroids, phototherapy, and in severe cases, methotrexate or immunosuppressive drugs.
Incidence by age distribution is bimodal: the first peak occurs in 16 to 22 years, and the second between 57 and 60 years.
Depending on the appearance and location of plaques can be defined several types of psoriasis. The most common form is psoriasis vulgaris. Other types are guttate psoriasis (in drops), reversed, erythrodermic and pustular.
Vulgar psoriasis – is characterized by the presence of red cards, well defined, round or oval, covered by thick crusts, white is blistered. Are usually located on the elbows, knees, scalp and buttocks.
Guttate Psoriasis – is manifested by a sudden onset of plate diameter 0, 5 -1, 5 mm, especially on the trunk in children and young adults. This form of psoriasis is caused by another disease or drugs (eg strep throat)
Inverted psoriasis – tiles appear inside joints (axillary region, inguinal, near the genitals) and are more wet than dry, and sometimes become painful because they are subject to friction.
Erythrodermic psoriasis – is characterized by gradual or sudden appearance of a diffuse erythema (almost all the skin is red and inflamed), and psoriatic plaques are less prominent or even absent. Psoriasizul often occurs in patients with erythrodermic psoriasis due to inappropriate use of topical corticosteroids or systemic or phototherapy.
Pustular psoriasis – characterized by the presence of plaques covered with white pustules, especially on the palmar and plantar surfaces.
Evolution and complications
Psoriasis flare-ups evolve in unpredictable and highly variable from one individual to another. Symptoms usually last 3 to 4 months, disappear for months or even years (remission) and then reappear in most cases.
About 7% of patients, psoriasis is accompanied by joint pain with swelling and stiffness. Speak in this case of psoriatic arthritis.
Causes and risk factors
The cause of psoriasis is unknown, but is frequently positive family history, suggesting a genetic component in many cases (family history of psoriasis are identified in a third of cases).
Psoriasis mechanism corresponds to accelerated cell renewal epidermis (top layer of skin) every 4 days, although normal cycle is 28 days. Since cells because life is the same, they accumulate and form thick crusts.
Although the cause is not known with precision, have been identified factors that trigger psoriasis:
- Local irritation (Koebner phenomenon)
- Beta-hemolytic streptococcus infection
- Some drugs (chloroquine, beta blockers, indomethacin, lithium, interferon alpha)
- Discontinuation of some medications (cortisone)
- Ingestion of toxic substances (alcohol, tobacco, etc.)
- Sleep disorders
- Genetic predisposition – over a third of patients, one or more family members also suffer from psoriasis. If a parent shows this condition, the risk for child varies between 5 and 10%.
- Immunological reactions against another disease (chickenpox)
- Reaction to a medication (lithium, beta-blockers) or vaccine
- A systemic infection (pharyngitis or streptococcal angina)
- Skin lesions
- Dry climate
- Prolonged exposure to sunlight or certain chemicals (disinfectants, paint thinners)
- Excessive alcohol consumption.
Diagnosis and treatment
In most cases the diagnosis is clinical, based on the appearance and distribution of lesions. Differential diagnosis is made with seborrheic dermatitis, lupus erythematosus, eczema, lichen planus, squamous cell carcinoma in situ (Bowen’s disease, especially when located in the trunk), lichen simplex chronicus. Biopsy is rarely necessary. The disease is evaluated according to severity as mild moderate or severe.
Unfortunately, there is no cure for psoriasis, and patients can not ever be sure of disappearance eruptions. However, there are medical treatments that reduce the intensity of rash during episodes of psoriasis.
For mild to moderate cases, topical ointments are usually prescribed emollient properties, creams, waxes and oils. They are designed to reduce descumarea, to relieve inflammation and soothe the skin, is more effective when applied immediately after bathing.
Salicylic acid is a keratolytic agent with softening effect scales, facilitating their removal and absorption of other topical agents. It is particularly useful in the treatment of scalp.
Ointments, solutions or tar-based shampoos have anti-inflammatory and reduce keratinocyte proliferation through a mechanical unknown. Are usually applied and removed during norpii morning. Can be used with topical corticosteroids or after exposure to ultraviolet B (UVB) in gradually increasing doses (Goeckerman regime).
Corticosteroids are used in the treatment of psoriasis with topical (local). Their efficiency is higher when applied during the night, covering the area of skin with a polyethylene film. A cream containing steroids can be applied without occlusion during the day. As improvement events, corticosteroids should be more often, or replace less potent preparations to reduce local atrophy, and telangiectasia formation of striations. After three weeks of using corticosteroids, it must be replaced with an emollient for 1 -2 weeks. The application long and extensive skin areas may exacerbate psoriasis. Systemic corticosteroids may be responsible for the exacerbation or development of pustular psoriasis and should not be used for any form of psoriasis.
Calcipotriol is a synthetic form of vitamin D3 and can be associated with topical corticosteroid therapy.
For severe cases of psoriasis may be prescribed drugs administered orally or by intramuscular injections: retinoids which reduce cell proliferation, methotrexate or cyclosporine, which diminishes the immune system. All this can lead to serious side effects (eye inflammation, hair loss, liver or kidney). To reduce these risks, a medication is generally suggested by rotation without term administration of a drug to exceed 24 months.
Methotrexate is the most effective treatment for severe psoriasis with complications (psoriatic arthritis), which does not respond to other forms of treatment (topical agents and fotochimioterapia PUVA).
Systemic retinoids (acitretin) may be indicated in severe cases of psoriasis vulgaris, pustular, and palmoplantar psoriasis. Due to its teratogenic (to cause fetal malfomarii) and long-term retention of acitretin in the body, the drug is contraindicated in pregnant women. Also, women are advised to have a pregnancy after at least 2 years after treatment.
Cyclosporine is an immunosuppressant used for several months (rarely 1 year) and alternated with other therapies.
Phototherapy and photo-chemotherapy
In patients with extensive skin damage or persistent rash may be used phototherapy and fotochimioterapia.
Inpatient phototherapy consists of exposure to ultraviolet radiation (UVB radiation in general), natural or artificial. Fotochimioterapia combines ultraviolet exposure by taking a photosensitizing drug (which sensitizes skin to the action of radiation).
Method is called PUVA therapy combining exposure to the drug psoralen ultraviolet A radiation. Radiation doses are increased gradually depending on patient tolerance. Short-term risks of PUVA therapy are negligible (especially burns). In contrast, long-term, this method can increase the risk of skin cancer.
Recent techniques allow exposure to UVB narrow spectrum, with lower risks. This UVB radiation therapy may be associated with the application of a photosensitiser, such as tar based preparations.
Tips for skin care
- Moderate exposure to sunlight can significantly improve an episode of psoriasis manifestations
- Cards easily blistered, with a daily bath (water should not be hot)
- Avoid scratching the affected areas as it may cause bleeding or irritation
- Avoid irritating hygiene products (eg, those containing alcohol)
- After each bath, apply a moisturizer to still damp skin – this is especially important in winter
- Maintaining a relatively low ambient temperatures
- Drink at least 8 glasses of water a day
To reduce the frequency and intensity of psoriatic flares:
- After sun exposure is recommended to apply a sunscreen with a high sun protection factor
- Alcohol consumption should be reduced or even eliminated completely
- Reduce stress – it is recognized that stress plays a role in the onset and exacerbation of psoriasis flares
- Patients can consult a psychologist or a psychotherapist to become aware of events or physical condition at the origin of some flares of psoriasis.