Psoriasis is a common, chronic skin condition. The result of a rapid buildup of skin cells, psoriasis causes red, raised, dry and cracked scaly patches, and even blisters, to form on the skin. In some cases, psoriasis affects the fingernails, causing yellowing and small depressions. Psoriasis can be mild, moderate or severe, and, in most cases, causes itching and burning in affected areas or skin.
Psoriasis is the result of an autoimmune disorder, in which skin cells replace themselves every 3 to 4 days, rather than the usual 30, creating a buildup of cells on the skin's surface, and causing symptoms to appear on the scalp, elbows, knees, hands, feet and genitals. Although there is no cure, there are several treatments available to effectively relieve symptoms. In the United States, more than seven million men, women and children have psoriasis.
Causes of Psoriasis
Psoriasis is caused by an immune-system disorder involving a type of white blood cell called a "T lymphocyte" (T cell). Although T cells usually travel through the body to fight off viruses and other foreign substances, in patients with psoriasis, they attack healthy skin cells. This causes an increased production of healthy skin cells, which then build up on the surface of the skin, causing scaling and patches. The symptoms of psoriasis can worsen as a result of certain triggers, including the following:
- Injury to the skin
- Alcohol consumption
Certain medications are also triggers for psoriasis.
Symptoms of Psoriasis
Symptoms of psoriasis vary depending on each patient, but often include the following:
- Red patches of skin covered with silvery scales
- Dry, cracked skin
- Itching or burning
- Thickened nails
For many people who have it, psoriasis is merely a cosmetic issue. In some cases, however, it causes severe pain, especially when associated with arthritis. The symptoms of psoriasis usually come and go; it is a cyclic disorder, with remissions and flareups occurring throughout a patient's life.
Types of Psoriasis
There are seven different types of psoriasis, each causing different symptoms. Some types are more common than others. Although patients usually have only one type of psoriasis at any given time, another type can appear once the first has cleared.
Plaque psoriasis is the most common type; it affects about 80 percent of psoriasis patients. It causes raised red lesions that are covered with silvery white scales, and usually appears on the elbows, knees, scalp and back.
Guttate psoriasis usually begins during childhood or early adulthood. It causes small red spots to appear on the skin of the torso, arms and legs, and is associated with bacterial infections such as strep throat.
Inverse psoriasis develops in the armpits or groin, under the breasts, or in other folds of skin. It manifests itself as bright-red lesions that can become irritated from sweat and friction. It is most common in overweight patients.
Pustular psoriasis causes white, pus-filled blisters that are surrounded by red areas of skin. It is often triggered by medication, ultraviolet light, pregnancy or infection, and is most common in adults.
Erythrodermic psoriasis is the least common type of psoriasis. It often causes redness and scaling on the whole body, and can lead to serious illness if left untreated.
Nail psoriasis affects the nails, causing them to thicken and yellow, and develop small pits in the nail bed. Patients with nail psoriasis are likely to also have a fungal infection.
Psoriatic arthritis is a combination of psoriasis and arthritis. It can cause swelling, pain and discoloration of the joints, in addition to the skin-related symptoms of psoriasis.
Treatment of Psoriasis
Treatment for psoriasis focuses on clearing the skin of current symptoms. Treatments for the root cause of psoriasis are intended to interrupt the abnormal cycle that has caused an increased production of skin cells. This can be achieved through topical treatment, oral medication, light therapies or a combination of the three.
Topical treatment for psoriasis usually includes the use of corticosteroids, vitamin D or topical retinoids. These topical medications target inflammation, skin-cell growth and DNA activity to effectively treat the symptoms of mild-to-moderate psoriasis.
Light therapy may be used in combination with topical treatments to slow the production of skin cells and improve the overall appearance of the skin. Light therapy includes exposure to natural sunlight or narrowband ultraviolet-B light.
Oral medications may be prescribed for severe cases of psoriasis, or those that are unresponsive to other types of treatment. Prescription oral medications include retinoids, methotrexate or cyclosporine.
A biologic can target, or quiet, only the part of the immune system that is overactive because of psoriasis. This means that biologics have less risk of causing problems with the liver, kidneys, and other organs than do other strong psoriasis medicines.
A biologic is an important treatment option for people with moderate-to-severe psoriasis, psoriatic arthritis, or both. For many people, taking a biologic was life changing because it helped control their symptoms when other treatments failed.
Patients will need to have some medical tests before a dermatologist can tell whether a biologic can be prescribed to treat the psoriasis. Blood tests and tuberculosis (TB) testing are typically required. Some patients need additional medical tests.
Studies show that the biologics approved to treat psoriasis and psoriatic arthritis can be very effective. For many people with moderate-to-severe psoriasis or psoriatic arthritis, a biologic may offer the most effective treatment available.