Psoriasis is a chronic inflammatory skin condition. It commonly appears as red elevated patches and flaking silvery scales, but it can take on other forms and appearances, and can range from mild to severe. The lesions can be painful, itchy, and may vary in size. The skin may also crack and bleed from the dry, flaky patches. Lesions can appear anywhere on the body, and the most common sites include the elbows, knees, scalp, chest, and lower back. Plaques tend to appear in the same place on both sides of the body.
The exact cause of psoriasis is not known, but it is believed by experts to involve a malfunctioning of the white blood cells in the immune system, and a consequent production of inflammation. Psoriasis can be permanent, or it may flare up, then subside, or even disappear altogether for awhile before another flare-up occurs. Some factors which may trigger a flare-up are:
Infection such as upper respiratory bacteria or viruses can actually cause someone to develop psoriasis.
Skin injury or a break in the skin, such as razor nick or burn, insect bite, cut, abrasion, sunburn, needle puncture (including from vaccination), blister, or bruise.
Stress can worsen symptoms, or a stressful event may even trigger the onset of psoriasis.
Weather, in particular, the dry and cold winter season, can adversely impact psoriasis because it dries and irritates the skin.
Psoriasis can develop at any age, but it is commonly seen in adults. Having a family history of psoriasis is a leading risk factor.
Different types of psoriasis include:
Plaque psoriasis - the most common form, occurring in about 90% of patients. It usually begins with red scaly patches, and can range from mild to severe, covering very small or extensive areas of the body.
Guttate psoriasis - typically has an abrupt onset, appearing in a few weeks, and is often quite extensive. The lesions that appear are small and "drop-like", and can most often be found on the trunk, arms, legs, or scalp. It usually develops following an upper respiratory infection, such as strep throat. Guttate psoriasis may resolve on its own without treatment, although it can become recurrent throughout life.
Pustular psoriasis - characterized by pus-filled pustules. It can be both wide-spread or localized, with localized pustules generally confined to the palms or soles of the feet. As the pustular lesions dry out, scales will gradually form.
Inverse psoriasis - occurs in skin folds where there tends to be pressure, friction, moisture, or perspiration, such as between the buttocks, the genitals, under breasts, or in the armpits. The lesions are usually smooth and red instead of raised and scaling.
Erythrodermic psoriasis - a rare but serious form of the disease marked primarily by widespread redness and inflammation that resembles a sunburn. It can develop from a severe sunburn, using certain medications (such as oral corticosteroids or lithium), or even suddenly stopping psoriasis treatment.
Treatment options will vary based on the type and severity of the disease, how large or widespread plaques are, and how well a patient responds to a given treatment. A physician may choose to combine two or more treatments for the best outcome. Some forms of treatments are:
Topical treatments, such as creams and ointments. These are usually the first treatment recommended, particularly for mild psoriasis. The aim is to slow down and regulate skin cell turnover, reduce inflammation, and suppress the immune system.
Systemic treatments work by helping to regulate and normalize skin cell turnover and suppressing the immune response that causes inflammation and plaques.
Light therapy, such as natural and artificial ultraviolet (UV) light can be used to treat psoriasis. Narrow Band UVB phototherapy emits a short wavelength of UV light that penetrates the outermost layer of skin. PUVA is another form of light therapy that combines psoralen, a drug taken either orally or topically, and UVA light exposure.
If you are having trouble with psoriasis, talk to your doctor about treatment options. You can also learn more about psoriasis by clicking the links below.