Psoriasis

Definition

Named for the Greek word psōra meaning itch, psoriasis is a chronic, non-contagious disease characterized by inflamed lesions covered with silvery-white scabs of dead skin.

Description

Normal skin cells mature and replace dead skin every 28 to 30 days. In psoriasis, the immune system triggers the immune system to make T cells, a type of white blood cell, that cause skin cells to mature in two to three days. Because the body cannot shed old skin as rapidly as the new cells appear, raised patches of dead skin form on the body.

Psoriasis is considered mild if it affects less than 5 percent of the surface of the body; moderate, if 5 to 30 percent of the skin is involved, and severe, if the disease affects more than 30 percent of the body surface.

There is no cure for psoriasis. The disease is managed through treatment. Psoriasis can seriously impact children's lives when the hands and feet are affected so the children cannot take notes or walk or play , or when the disease becomes so widespread that the immune system becomes compromised. Children also experience low self-esteem and depression because of the disfiguring aspects of the disease.

Types of psoriasis

Dermatologists distinguish different forms of psoriasis according to what part of the body is affected, how severe symptoms are, how long they last, and the pattern formed by the scales. Though children usually have only one form of the disease, some do experience two more types of psoriasis throughout their lifetimes.

PLAQUE PSORIASIS Plaque psoriasis (psoriasis vulgaris), the most common form of the disease, is characterized by small, red bumps that enlarge, become inflamed, and form scales. The top scales flake off easily and often, but those beneath the surface of the skin clump together. Removing these scales exposes tender skin, which bleeds and causes the plaques (inflamed patches of skin) to grow.

Plaque psoriasis can develop on any part of the body, but most often occurs on the elbows, knees, scalp, and trunk. Patches of psoriasis are found in the scalp for nearly half of all psoriasis sufferers.

GUTTATE PSORIASIS Named for the Latin word gutta, which means "a drop," guttate psoriasis is characterized by small, red, drop-like dots that enlarge rapidly and may be somewhat scaly. Often found on the arms, legs, trunk, scalp, and sometimes in the diaper area, guttate psoriasis can clear up without treatment or disappear and resurface in the form of plaque psoriasis.

Guttate psoriasis is the most common form of psoriasis in children. It usually first appears in children around four or five years old after a streptococcal infection.

PUSTULAR PSORIASIS Pustular psoriasis usually occurs in adults but can occur in children and adolescents. It is characterized by blister-like lesions filled with non-infectious pus and surrounded by reddened skin. Pustular psoriasis, which can be limited to one part of the body or can be widespread, may be the first symptom of psoriasis or develop in a patient with chronic plaque psoriasis.

Generalized pustular psoriasis is also known as Von Zumbusch pustular psoriasis. Widespread, acutely painful patches of inflamed skin develop suddenly. Pustules appear within a few hours, then dry, and peel within two days. It can make life-threatening demands on the heart and kidneys.

Palomar-plantar pustulosis (PPP) generally appears between the ages of 20 and 60.

INVERSE PSORIASIS Inverse psoriasis occurs in the armpits and groin, under the breasts, and in other areas where skin flexes or folds. This disease is characterized by smooth, inflamed lesions and can be debilitating.

ERYTHRODERMIC PSORIASIS Characterized by severe scaling, itching , and pain that affects most of the body, erythrodermic psoriasis disrupts the body's chemical balance and can cause severe illness or even death when the body's immune system becomes compromised. Erythrodermic psoriasis interferes with the body's ability to control temperature and prevent infections. This particularly inflammatory form of psoriasis can be the first sign of the disease but often develops in patients with a history of plaque psoriasis.

PSORIATIC ARTHRITIS About 10 percent of patients with psoriasis develop a complication called psoriatic arthritis. This type of arthritis can be slow to develop and mild, or it can develop rapidly. Symptoms of psoriatic arthritis include:

• joint discomfort, swelling, stiffness, or throbbing
• swelling in the toes and ankles
• pain in the digits, lower back, wrists, knees, and ankles
• eye inflammation or pink eye (conjunctivitis)

Children who have psoriatic arthritis also have nail deformations, usually pitting of the fingernails or toenails. Size, shape, and depth of the marks vary, and affected nails may thicken, yellow, or crumble. The skin around an affected nail is sometimes inflamed, and the nail may peel away from the nail bed.

Demographics

Psoriasis affects 4.5 million Americans and is slightly more common in women than in men. Although the disease can develop at any time, a third of all cases occur in childhood with 10 to 15 percent of them being diagnosed in children under ten. It appears between the ages of 15 and 35. It is rare in infants but does occur. Nearly 20,000 U.S. children are diagnosed with psoriasis every year. Psoriasis affects people of all ethnicities, but fair-skinned individuals have a slightly higher incidence.

About 1.5 million Americans have moderate to severe psoriasis. Of them, 75 percent report that their disease has a serious impact on their daily lives. One-third report sleeping problems, disruptions with their normal routine, and negative self-image because of the disease.

In adults, psoriasis can be serious enough that four hundred people are granted disability by the Social Security Administration each year, and having psoriasis disqualifies individuals from serving in the military. Annually, three hundred and fifty people die annually from psoriasis or complications of treatment.

Nearly one million people in the United States have psoriatic arthritis. Though psoriatic arthritis usually develops between the age of 30 and 50, it does occur in children. About 10 to 30 percent of psoriasis patients have psoriatic arthritis, but the condition can occur before the characteristic scaly lesions occur.

Having one parent with psoriasis increases a child's risk of developing the disease to 20 to 25 percent. If both parents have psoriasis, the risk is doubled.

Patients with psoriasis make 2.4 million visits to dermatologists each year, with costs exceeding $3 million annually.

Causes and symptoms

Causes

The cause of psoriasis is, as of 2004, unknown, but research suggests that it is genetic and is related to the immune-system. Having both parents with the disease increases a child's risk by 50 percent.

Psoriasis is usually cyclical, with episodes flaring up for weeks or months throughout the child's life and then receding. Certain factors, however, do seem to trigger bouts of the disease. Injury to the skin seems to precipitate many episodes of plaque psoriasis, usually within seven to ten days. This is called the Koebner reaction. Streptococcal infections are associated with guttate psoriasis and some plaque psoriasis cases. Both trauma and certain bacteria may also trigger psoriatic arthritis.

Environmental factors are also implicated in reoccurrence of psoriasis. Exposure to cold temperatures can trigger episodes of the disease. Though sunlight is usually beneficial to most patients, for a few children, too much sun can cause a flare up or worsen the condition.

Some drugs have been found to aggravate psoriasis. Antimalarial drugs, beta-blockers used to treat high blood pressure, and lithium, a drug used to treat depression and bi-polar disorder, can make episodes worse in some individuals. Non-steroid anti-inflammatory (NSAID) drugs, such as ibuprofen or naproxen used to manage pain and inflammation can also aggravate psoriasis.

During puberty , adolescents report more frequent flare ups and more severe ones. The hormonal changes within their bodies seem to trigger the immune system.

Stress is also a factor in increased frequency of psoriatic episodes. Because stress pumps large amounts of adrenalin, a hormone, into the body, the immune system is overstimulated and reacts by triggering flare ups of the disease.

Symptoms

The most common symptoms of psoriasis are skin rashes or red patches covered with white scales that may itch or burn. In plaque psoriasis, the skin may crack and bleed and is susceptible to infection. When the scales are removed, the skin underneath is deep red and shiny and may bleed. Psoriasis on the scalp is distinguished from seborrheic dermatitis , or dandruff, because the scales of psoriasis are dry, not greasy. There may be a red drop-like rash (guttate psoriasis) or patches of scaly skin that crack and ooze pus (pustular psoriasis).

In young children, the scaly patches in plaque psoriasis do not appear as thick or as scaly as those of adults. Psoriasis appears often in the diaper area and affects the face more in children than adolescents or adults.

When to call the doctor

Many children routinely see their doctors to supervise their regime of treatment for psoriasis flare ups. Others only see their doctors at the first sign of a recurrence of the disease. There are circumstances, however, when the doctor should be notified. If a treatment does not seem to be working, episodes worsen with treatment, or the child experiences a serious side effect to medications give, the doctor should be consulted to discuss alternative treatment. If there are signs of infections, such as red streaks on the skin or pus, or if there is fever or increased pain, the doctor should be called immediately.

Diagnosis

A complete medical history and examination of the skin, nails, and scalp are the basis for a diagnosis of psoriasis. In some cases, a microscopic examination of skin cells is also performed.

Blood tests can distinguish psoriatic arthritis from other types of arthritis. Rheumatoid arthritis, in particular, is diagnosed by the presence of a particular antibody present in the blood. That antibody is not present in the blood of patients with psoriatic arthritis.

Treatment

Age, general health, lifestyle, and the severity and location of symptoms influence the type of treatment used to reduce inflammation and decrease the rate at which new skin cells are produced. Because the course of this disease varies with each individual, doctors must experiment with or combine different treatments to find the most effective therapy for a particular patient.

Treating children with this disease with drugs is problematic. Though treatment regimes have been developed that are effective on adults, research has not been conducted sufficiently on children, except in the area of psoriatic arthritis. Treatment in children is usually not aggressive because of their small, developing bodies. Long-term use can produce toxicity so potent drugs, such as methotrexate (MTX) and cyclosporine, are not used with children. Although MTX is sometimes used in extreme cases for brief amounts of time. Topical steriods are also not used on children because their bodies can absorb the steriods in the medication.

Mild psoriasis

Typically, steroid creams and ointments are commonly used to treat mild or moderate psoriasis in adults. These topical ointments are not generally used with children for mild psoriasis. However, new creams that are used in treating eczema appear to be effective in treating psoriasis as well and do not appear to have long-term problems. In addition, tazarotene (Tazorac), a drug approved by the United States Food and Drug Administration (FDA) in 1997, is proving to be effective for mild-to-moderate plaque psoriasis. This water-based gel has chemical properties similar to vitamin A.

A more subdued approach is undertaken with children who have less severe psoriasis. Brief daily doses of natural sunlight can significantly relieve most symptoms. Sunburn , however, has the opposite effect.

Moisturizers and bath oils are used to loosen scales, soften skin, and eliminate the itch. Adding a cup of oatmeal to a tub of bath water is also helpful. Salicylic acid (an ingredient in aspirin) can be used to remove dead skin or increase the effectiveness of other therapies.

Moderate psoriasis

Administered under medical supervision, ultraviolet light B (UVB) is used to control psoriasis that covers many areas of the body or that has not responded to topical preparations. Doctors combine UVB treatments with topical medications to treat some patients and sometimes prescribe home phototherapy, in which the parent administers the UVB treatments.

Tanning beds use ultraviolet A and produce a more intense experience. Adolescents should avoid tanning salons and should sunbathe but without tanning. Any sun exposure or UVB treatment should be coordinated with a dermatologist.

Severe psoriasis

Methotrexate (MTX), given as a pill or as an injection, is sometimes used in extreme cases to alleviate symptoms of severe psoriasis or psoriatic arthritis. Patients who take MTX must be carefully monitored to prevent liver damage.

Enbrel is another drug dermatologists prescribe for children. It appears to be very safe when used for long periods of time.

A new self-injected medication called efalizumab (Raptiva) has the potential to be effective for severe cases of psoriasis. Since it is suppresses the immune system, its use with children or over the long-term is cautioned because it can increase the risk of infection.

Psoriatic arthritis can also be treated with NSAIDs, such as acetaminophen (Tylenol) or aspirin. Hot compresses and warm water soaks may also provide some relief for painful joints.

Photochemotherapy (PUVA) is a medically supervised procedure that combines medication with exposure to ultraviolet light (UVA) to treat localized or widespread psoriasis. An individual with widespread psoriasis that has not responded to treatment may enroll in one of the day treatment programs conducted at special facilities throughout the United States. Psoriasis patients who participate in these intensive sessions are exposed to UVA and given other treatments for six to eight hours a day for two to four weeks.

Alternative treatment

Non-traditional psoriasis treatments include:

• soaking in warm water and German chamomile (Matricaria recutita ) or bathing in warm salt water
• drinking as many as three cups a day of hot tea made with one or a combination of the following herbs: burdock (Arctium lappa ) root, dandelion (Taraxacum mongolicum ) root, Oregon grape (Mahonia aquifolium ), sarsaparilla (Smilax officinalis ), and balsam pear (Momardica charantia )
• taking two 500-mg capsules of evening primrose (Oenothera biennis ) oil a day (Pregnant women should not use evening primrose oil, and patients with liver disease or high cholesterol should use it only under a doctors supervision.)
• eating a diet that includes plenty of fish, turkey, celery (for cleansing the kidneys), parsley, lettuce, lemons (for cleansing the liver), limes, fiber, and fruit and vegetable juices
• eating a diet that eliminates animal products high in saturated fats, since they promote inflammation
• drinking plenty of water (at least eight glasses) each day
• taking nutritional supplements including folic acid , lecithin, vitamin A, vitamin E, selenium, and zinc
• regularly imagining clear, healthy skin

Other helpful alternative approaches include identifying and eliminating food allergens from the diet, enhancing the function of the liver, augmenting the hydrochloric acid in the stomach, and completing a detoxification program. Constitutional homeopathic treatment, if properly prescribed, can also help resolve psoriasis.

Prognosis

Most cases of psoriasis can be controlled, and most people who have psoriasis can live normal lives. However, some people who have psoriasis are so self-conscious and embarrassed about their appearance that they become depressed and withdrawn. Others may become disabled because of psoriatic arthritis or because their psoriasis affects their hands and feet so that they cannot walk or handle objects.

Prevention

Psoriasis cannot be prevented. However, recurrences can be avoided or minimized by maintaining a healthy lifestyle by getting plenty of sleep , eating a balanced diet, participating in regular exercise , and minimizing stress. Avoiding overexposure to cold temperatures, sunburn, and skin irritants, such as drying soaps and lotions, can also minimize flare-ups. Not smoking or drinking alcohol can also prevent or minimize some episodes.

Parental concerns

Children living with psoriasis often find the disease overwhelming. It is an emotionally charged disease that can have a child feeling anger one minute and deep depression the next. Because the disfigurement of their skin, though often temporary, is sometimes quite pronounced, children will turn inward, avoiding contact with friends or relatives. School can be particularly traumatizing due to teasing by other children. Teenagers, who already feel awkward and ugly, may feel worse during flare-ups of the disease. Complicating this already emotional situation is the discouragement of treatments that do not work as expected and the uncertainty of finding something that will work.

Parents can help their children by providing education about the psoriasis. This is the first step in managing the disease and feeling some control in their lives. Sometimes this education includes discussing the disease with the childs teachers or the parents of their friends so that these adults will understand more about the emotional state of the child.

Parents can listen to their children when they are able to talk about their feelings about the disease. Emphasizing their childrens strengths, especially when these children appear sad or depressed, and encouraging them to stay active and see their friends can help a child cope with the disease.

Sometimes, participating in a childrens psoriasis support group may be helpful. In addition, sending the child to a special camp for school age children with childhood skin diseases can help them learn tools for coping with the disease as well as establish a support system.

Children can often feel shame as well as guilt, thinking that they have somehow brought on the disease. Coupled with anger and resentment, these powerful emotions can contribute to stress, which can trigger the recurrence of the disease. Stress reduction techniques, such as exercise, yoga , and meditation, are also helpful.

Parents should be available to their child and offer as much tangible and emotional support they can. However, they should not encourage the child to become too dependent on the parent or others. Parents can also help children find creative solutions to deal with teasing, camouflage their lesions, and educate their peers about the disease. One of the most important lessons parents can teach their child, who is living with psoriasis, is not to be embarrassed because of the disease. Psoriasis can be treated matter-of-factly as people do diabetes, another chronic disorder.

KEY TERMS

Adrenaline —Another name for epinephrine, the hormone released by the adrenal glands in response to stress. It is the principal blood-pressure raising hormone and a bronchial and intestinal smooth muscles relaxant.

Arthritis —A painful condition that involves inflammation of one or more joints.

Plaque —Inflamed patches of skin present in some forms of psoriasis.

T cell —A type of white blood cell that is produced in the bone marrow and matured in the thymus gland. It helps to regulate the immune system's response to infections or malignancy.

See also Depressive disorders; Itching; Self-esteem.

Resources

BOOKS

Cram, David L. Coping with Psoriasis: A Patients Guide to Treatment. Omaha, NB: Addicus Books, 2000.

Scott, Jerry G. Psoriasis: The Real Way Out: A Self-Education Guide to Complete Natural Healing. Kenora, Ont.: Psoriasis Connection International, 2003.

PERIODICALS

"Generic Name: Efalizumab Injection." Drug Topics 148 (January 26, 2004): HSE21.

Harrar, Sari. "New, Inject-it-yourself." Prevention 56 (2004): 48.

ORGANIZATIONS

American Academy of Dermatology. 930 N. Meacham Road, PO Box 4014, Schaumburg, IL 601684014. Web site: <www.aad.org>.

American Skin Association Inc. 150 E. 58th St., 3rd floor, New York, NY 101550002. Web site: <www.americanskin.org>.

National Psoriasis Foundation. 6600 SW 92nd Ave., Suite 300, Portland, OR 97223. Web site: <www.psoriasis.org>.

WEB SITES

"Juvenile Psoriatic Arthritis." Arthritis Foundation, 2004. Available online at <www.arthritis.org/conditions/diseasecenter/juvenilepsoriaticarthritis.asp>(accessed December 11, 2004).

Janie Franz Maureen Haggerty

Psoriasis

Definition

Psoriasis is a chronic, non-contagious disease characterized by inflamed hyperproliferative lesions covered with silvery-white scabs of dead skin.

Description

Psoriasis, which affects at least four million Americans, is slightly more common in women than in men. Although the disease can develop at any time, 10–15% of all cases are diagnosed in children under 10, and the average age at the onset of symptoms is 28 years of age. Psoriasis is most common in fair-skinned people and relatively rare in dark-skinned individuals, although the rate among African Americans appears to be slowly rising.

Normal skin cells mature and replace dead skin every 28–30 days. Psoriasis causes skin cells to mature in less than a week. Because the body can't shed the old skin as rapidly as new cells are rising to the surface, raised patches of dead skin develop on the arms, back, chest, elbows, legs, nails, folds between the buttocks, and scalp.

Psoriasis is considered mild if it affects less than 5% of the surface of the body, moderate if 5–30% of the skin is involved, and severe if the disease affects more than 30% of the body surface.

Types of psoriasis

Dermatologists distinguish different forms of psoriasis according to what part of the body is affected, how severe symptoms are, how long they last, and the pattern formed by the scales.

PLAQUE PSORIASIS. Plaque psoriasis (psoriasis vulgaris), the most common form of the disease, is characterized by small, red bumps that enlarge, become inflamed, and form scales. The top scales flake off easily and often, but those beneath the surface of the skin clump together. Removing these scales exposes tender skin, which bleeds and causes the plaques (inflamed patches) to grow.

Plaque psoriasis can develop on any part of the body, but most often occurs on the elbows, knees, scalp, and trunk.

SCALP PSORIASIS. At least 50 of every 100 people who have any form of psoriasis have scalp psoriasis. This form of the disease is characterized by scale-capped plaques on the surface of the skull.

NAIL PSORIASIS. The first sign of nail psoriasis is usually pitting of the fingernails or toenails. Size, shape, and depth of the marks vary, and affected nails may thicken, yellow, or crumble. The skin around an affected nail is sometimes inflamed, and the nail may peel away from the nail bed.

GUTTATE PSORIASIS. Named for the Latin word gutta, which means "a drop," guttate psoriasis is characterized by small, red, drop-like dots that enlarge rapidly and may be somewhat scaly. Often found on the arms, legs, and trunk and sometimes in the scalp, guttate psoriasis can clear up without treatment or disappear and resurface in the form of plaque psoriasis.

PUSTULAR PSORIASIS. Pustular psoriasis usually occurs in adults. It is characterized by blister-like lesions filled with non-infectious pus and surrounded by reddened skin. Pustular psoriasis, which can be limited to one part of the body (localized) or can be widespread, may be the first symptom of psoriasis or develop in a patient with chronic plaque psoriasis.

Generalized pustular psoriasis is also known as Von Zumbusch pustular psoriasis. Widespread, acutely painful patches of inflamed skin develop suddenly. Pustules appear within a few hours, then dry and peel within two days.

Generalized pustular psoriasis can make life-threatening demands on the heart and kidneys.

Palomar-plantar pustulosis (PPP) generally appears between the ages of 20 and 60. PPP causes large pustules to form at the base of the thumb or on the sides of the heel. In time, the pustules turn brown and peel. The disease usually becomes much less active for a while after peeling.

Acrodermatitis continua of Hallopeau is a form of PPP characterized by painful, often disabling, lesions on the fingertips or the tips of the toes. The nails may become deformed, and the disease can damage bone in the affected area.

INVERSE PSORIASIS. Inverse psoriasis occurs in the armpits and groin, under the breasts, and in other areas where skin flexes or folds. This disease is characterized by smooth, inflamed lesions and can be debilitating.

ERYTHRODERMIC PSORIASIS. Characterized by severe scaling, itching , and pain that affects most of the body, erythrodermic psoriasis disrupts the body's chemical balance and can cause severe illness. This particularly inflammatory form of psoriasis can be the first sign of the disease, but often develops in patients with a history of plaque psoriasis.

PSORIATIC ARTHRITIS. About 10% of patients with psoriasis develop a complication called psoriatic arthritis. This type of arthritis can be slow to develop and mild, or it can develop rapidly. Symptoms of psoriatic arthritis include:

• joint discomfort, swelling, stiffness, or throbbing
• swelling in the toes and ankles
• pain in the digits, lower back, wrists, knees, and ankles
• eye inflammation

Causes & symptoms

The cause of psoriasis is unknown, but research related to the Human Genome Project is mapping the genetic component of the disease. As of late 2001, accumulated evidence indicates that psoriasis is a multifactorial disorder, which means that it is the end result of a number of different factors. It appears to be caused by the combined action of multiple disease genes in a single individual that are triggered by irritants in the environment. Factors that increase the risk of developing psoriasis include:

• blood relatives with psoriasis
• stress
• exposure to cold temperatures
• injury, illness, or infection
• steroids and other medications
• mechanical stress (leaning on knees or skin exposure to chemicals, for example)

Trauma and certain bacteria may trigger psoriatic arthritis in patients with psoriasis.

Diagnosis

A medical history and physical examination is the basis for a diagnosis of psoriasis. In some cases, a microscopic examination of skin cells is also performed.

Blood tests can distinguish psoriatic arthritis from other types of arthritis.

Treatment

Psoriasis treatments include:

• Soaking in warm water and German chamomile (Matricaria recutita ) or bathing in warm salt water.
• Drinking as many as three cups a day of hot tea made with one or a combination of the following herbs: burdock root (Arctium lappa ), dandelion (Taraxacum mongolicum ) root, Oregon grape root (Mahonia aquifolium ), sarsaparilla (Smilax officinalis ), and balsam pear (Momardica charantia ).
• Taking two 500-mg capsules of evening primrose oil (Oenothera biennis ) a day. Pregnant women should not use evening primrose oil, and patients with liver disease or high cholesterol should use it only under a doctor's supervision.
• Eating a diet that includes plenty of fish, turkey, celery (for cleansing the kidneys), parsley , lettuce, lemons (for cleansing the liver), limes, fiber, and fruit and vegetable juices.
• Eating a diet that eliminates animal products high in saturated and unsaturated fats, such as fried foods, dairy products, and fatty meats, that promote inflammation.
• Drinking plenty of water (at least eight glasses) each day.
• Regularly imagining clear, healthy skin.

Other helpful alternative approaches include identifying and eliminating food allergens from the diet; enhancing liver function; augmenting the supply of hydrochloric acid in the stomach; and completing a detoxification program. Constitutional homeopathic treatment, if properly prescribed, can sometimes help resolve psoriasis.

Allopathic treatment

Age, general health, lifestyle, and the severity and location of symptoms influence the type of treatment used to reduce inflammation and decrease the rate at which new skin cells are produced. Because the course of this disease varies with each individual, doctors must experiment with or combine different treatments to find the most effective therapy for a particular patient.

Mild–moderate psoriasis

Steroid creams and ointments are commonly used to treat mild or moderate psoriasis, and steroids are sometimes injected into the skin of patients with a limited number of lesions. In mid-1997, the United States Food and Drug Administration (FDA) approved the use of tazarotene (Tazorac) to treat mild-to-moderate plaque psoriasis. This water-based gel has chemical properties similar to Vitamin A .

Brief daily doses of natural sunlight can significantly relieve symptoms. Sunburn , however, has the opposite effect.

Certain moisturizers and bath oils can loosen scales, soften skin, and may eliminate the itch. (Often petroleum-based, coal tar-based, or other greasy ointments are used.) Adding a cup of oatmeal to a tub of bath water or using Aveeno in the bath can soothe the itch. Dilute, topical salicylic acid (an ingredient in aspirin) can be used to remove dead skin or increase the effectiveness of other therapies.

Moderate psoriasis

Administered under medical supervision, ultraviolet light B (UVB) is used to control psoriasis that covers many areas of the body or that has not responded to other treatment. Doctors combine UVB treatments with topical medications to treat some patients and sometimes prescribe home phototherapy, in which the patient administers his own UVB treatments.

Photochemotherapy (PUVA) is a medically super-vised procedure that combines medication with exposure to ultraviolet light (UVA) to treat localized or widespread psoriasis. An individual with wide-spread psoriasis that has not responded to treatment may enroll in one of the day treatment programs conducted at special facilities throughout the United States. Psoriasis patients who participate in these intensive sessions are exposed to UVB and given other treatments for six to eight hours a day for two to four weeks.

A newer form of treatment that has several advantages over standard phototherapy is therapy with an excimer laser system. Laser treatment for psoriasis uses a carefully focused beam of ultraviolet light that not only relieves symptoms quickly but also minimizes exposure of healthy skin to the ultraviolet rays.

Severe psoriasis

Methotrexate (MTX) can be given as a pill or as an injection to alleviate symptoms of severe psoriasis or psoriatic arthritis. Patients who take MTX must be carefully monitored by a doctor who checks blood liver enzymes to prevent liver damage.

Psoriatic arthritis can also be treated with nonsteroidal anti-inflammatory drugs (NSAIDs), like acetaminophen (Tylenol) or aspirin. Hot compresses and warm water soaks may also provide some relief for painful joints.

Other medications used to treat severe psoriasis include etrentinate (Tegison) and isotretinoin (Accutane), whose chemical properties are similar to those of Vitamin A. Most effective in treating pustular or erythrodermic psoriasis, Tegison also relieves some symptoms of plaque psoriasis. Tegison can enhance the effectiveness of UVB or PUVA treatments and reduce the amount of exposure necessary.

Accutane is a less effective psoriasis treatment than Tegison, but can cause many of the same side effects, including nosebleeds , inflammation of the eyes and lips, bone spurs, hair loss , and birth defects. Tegison is stored in the body for an unknown length of time, and should not be taken by a woman who is pregnant or planning to become pregnant. A woman should use reliable birth control while taking Accutane and for at least one month before and after her course of treatment.

Cyclosporin emulsion (Neoral) is used to treat stubborn cases of severe psoriasis. Cyclosporin is also used to prevent rejection of transplanted organs, and Neoral, approved by the FDA in 1997, should be particularly beneficial to psoriasis patients who are young children or African Americans, or those who have diabetes. The drawback to use of cyclosporin, however, is that it has been implicated in an increased risk of skin cancer for psoriasis patients. Researchers in Boston reported toward the end of 2001 that psoriasis patients who had been given cyclosporin as part of their treatment developed three times as many squamous cell cancers as those who had not. Patients who had taken cyclosporin for longer than three months were four times as likely to develop skin cancers.

A promising new medication for psoriasis that is in the clinical testing stage as of early 2002 is a drug called Alefacept. Alefacept targets the T-cells that cause psoriasis without suppressing the patient's immune system. The new drug not only relieves the symptoms of psoriasis more rapidly than current treatments, but patients also remain symptom-free longer.

Other conventional treatments for psoriasis include:

• Capsaicin (Capsicum frutecens ), an ointment that can stop production of the chemical that causes the skin to become inflamed and halts the runaway production of new skin cells. Capsaicin is available without a prescription, but should be used under a doctor's supervision to prevent burns and skin damage.
• Hydrocortisone creams, topical ointments containing a form of vitamin D called calcitriol, and coal-tar shampoos and ointments can relieve symptoms but may cause such side effects as folliculitis (inflammation of hair follicles) and heightened risk of skin cancer .

Expected results

Most cases of psoriasis can be managed. However, some people who have psoriasis are so self-conscious and embarrassed about their appearance that they become depressed and withdrawn. The Social Security Administration grants disability benefits to about 400 psoriasis patients each year.

KEY TERMS

Plaque

—An area or patch of inflamed skin. The most common form of psoriasis is plaque psoriasis.

Prevention

A doctor should be notified if:

• Psoriasis symptoms appear or reappear after treatment.
• Pustules erupt on the skin and the patient experiences fatigue , muscle aches, and fever .
• Unfamiliar, unexplained symptoms appear.

Resources

BOOKS

Gottlieb, Bill, ed. New Choices in Natural Healing. Emmaus, PA: Rodale Press, Inc., 1995.

The Medical Advisor: The Complete Guide to Alternative and Conventional Treatments. Alexandria, VA: Time-Life, Inc., 1995.

PERIODICALS

Elder, James T., Rajan P. Nair, Tilo Henseler, et al. "The Genetics of Psoriasis 2001: The Odyssey Continues." Archives of Dermatology 137 (November 2001): 1447-1454.

Franz, Rachel. "Trials Show Positive Results for New Psoriasis Treatment." Dermatology Nursing 13 (December 2001): 445.

"Psoriasis Patients at Increased Risk of Skin Cancer." Cancer Weekly (October 16, 2001): 4.

"Revolutionary New Laser Treatment Reaches Patients." Medical Devices & Surgical Technology Week (October 21, 2001): 30.

Zoler, Mitchel L. "Psoriasis Generally Mild in African Americans." Skin & Allergy News 32 (October 2001): 33.

ORGANIZATIONS

American Academy of Dermatology. P.O. Box 681069, Schaumburg, IL 60618-4014. (703) 330-0230. <www.aad.org>.

American Skin Association, Inc. 150 E. 58th Street, 3rd floor, New York, NY 10155-0002. (212) 688-6547.

National Psoriasis Foundation. 6600 S.W. 92nd Avenue, Suite 300, Portland, OR 97223. (800) 723-9166. <www.psoriasis.org>.

Maureen Haggerty

Rebecca J. Frey, PhD

Psoriasis

Definition

Psoriasis is a non-contagious skin condition characterized by inflamed lesions covered with silvery-white scabs of dead skin. psoriasis occurs most commonly on the elbows, knees, trunk, and scalp. Psoriasis is an autoimmune disorder that most often begins between the ages of 15 and 35, but can start at any age.

Description

Psoriasis, which affects at least four million Americans, is slightly more common in women than in men. Although the disease can develop at any time, 10–15% of all cases are diagnosed in children under 10, and the average age at the onset of symptoms is 28. Psoriasis is most common in fair-skinned people and extremely rare in dark-skinned individuals.

Normal skin cells mature and replace dead skin every 28–30 days. Psoriasis causes skin cells to mature in less than a week. Because the body can't shed old skin as rapidly as new cells are rising to the surface, raised patches of dead skin develop on the arms, back, chest, elbows, legs, nails, folds between the buttocks, and scalp.

Psoriasis is considered mild if it affects less than 5% of the surface of the body; moderate, if 5–30% of the skin is involved, and severe, if the disease affects more than 30% of the body surface.

Types of psoriasis

Dermatologists distinguish different forms of psoriasis according to what part of the body is affected, how severe symptoms are, how long they last, and the pattern formed by the scales.

plaque psoriasis Plaque psoriasis (psoriasis vulgaris), the most common form of the disease, is characterized by small, red bumps that enlarge, become inflamed, and form scales. The top scales flake off easily and often, but those beneath the surface of the skin clump together. Removing these scales exposes tender skin, which bleeds and causes the plaques (inflamed patches) to grow.

Plaque psoriasis can develop on any part of the body, but most often occurs on the elbows, knees, scalp, and trunk.

scalp psoriasis At least 50 of every 100 people who have any form of psoriasis have scalp psoriasis. This form of the disease is characterized by scalecapped plaques on the surface of the skull.

nail psoriasis The first sign of nail psoriasis is usually pitting of the fingernails or toenails. Size, shape, and depth of the marks vary, and affected nails may thicken, yellow, or crumble. The skin around an affected nail is sometimes inflamed, and the nail may peel away from the nail bed.

guttate psoriasis Named for the Latin word gutta, which means “a drop,” guttate psoriasis is characterized by small, red, drop-like dots that enlarge rapidly and may be somewhat scaly. Often found on the arms, legs, and trunk and sometimes in the scalp, guttate psoriasis can clear up without treatment or disappear and resurface in the form of plaque psoriasis.

pustular psoriasis Pustular psoriasis usually occurs in adults. It is characterized by blister-like lesions filled with non-infectious pus and surrounded by reddened skin. Pustular psoriasis, which can be limited to one part of the body (localized) or can be widespread, may be the first symptom of psoriasis or develop in a patient with chronic plaque psoriasis.

Generalized pustular psoriasis is also known as Von Zumbusch pustular psoriasis. Widespread, acutely painful patches of inflamed skin develop suddenly. Pustules appear within a few hours, then dry and peel within two days.

Generalized pustular psoriasis can make life-threatening demands on the heart and kidneys.

Palomar-plantar pustulosis (PPP) generally appears between the ages of 20 and 60. PPP causes large pustules to form at the base of the thumb or on the sides of the heel. In time, the pustules turn brown and peel. The disease usually becomes much less active for a while after peeling.

Acrodermatitis continua of Hallopeau is a form of PPP characterized by painful, often disabling, lesions on the fingertips or the tips of the toes. The nails may become deformed, and the disease can damage bone in the affected area.

inverse psoriasis Inverse psoriasis occurs in the armpits and groin, under the breasts, and in other areas where skin flexes or folds. This disease is characterized by smooth, inflamed lesions and can be debilitating.

erythrodermic psoriasis Characterized by severe scaling, itching , and pain that affects most of the body, erythrodermic psoriasis disrupts the body's chemical balance and can cause severe illness. This particularly inflammatory form of psoriasis can be the first sign of the disease, but often develops in patients with a history of plaque psoriasis.

psoriatic arthritis About 10% of partients with psoriasis develop a complication called psoriatic arthritis. This type of arthritis can be slow to develop and mild, or it can develop rapidly. Symptoms of psoriatic arthritis include:

• joint discomfort, swelling, stiffness, or throbbing
• swelling in the toes and ankles
• pain in the digits, lower back, wrists, knees, and ankles
• eye inflammation or pink eye (conjunctivitis)

Demographics

Most cases of psoriasis appear in people between the ages of 15 and 35, but can affect any age group. In older adults, the complications of psoriasis can occur in an immune system already weakened by other disorders. It is estimated that between 5.8 and 7.5 million Americans suffer from psoriasis, or approximately 2.2 percent. Worldwide it affects 125 million people, according to NPF reporting from World Psoriasis Day counts. Also according to NPF, 11 percent of people who are diagnosed with psoriasis, also have psoriatic arthritis—most likely to appear between the ages of 35 and 50, but can appear at any time. As of 2008, the rate of psoriasis in Caucasian Americans is 2.5 percent. In African Americans, the rate is 1.3 percent—even though people of all races are considered to be more or less at equal risk. Of those people who have psoriasis, one out of three of them have a relative also suffering from it. If a parent has the condition, a child has a 10 percent chance of contracting the ailment. If both parents have it, the child's risk goes up to 50 percent of

acquiring it. Cases can occur in infants but the incidence is considered rare.

Those persons with HIV/AIDS due to a weakened immune system are also more vulnerable to psoriasis than adults with healthy immune systems. In older adults with a history of the condition, taking care to avoid stress and maintaining a healthy diet in order to lessen the outbreaks or makethem less likely to occur due to a healthy immune system are two essential factors.

Causes and symptoms

The cause of psoriasis is unknown, but research suggests that an immune-system malfunction triggers the disease. Factors that increase the risk of developing psoriasis include:

• family history
• stress
• exposure to cold temperatures
• injury, illness, or infection
• steroids and other medications
• race

Trauma and certain bacteria may trigger psoriatic arthritis in patients with psoriasis.

Diagnosis

A complete medical history and examination of the skin, nails, and scalp are the basis for a diagnosis of psoriasis. In some cases, a microscopic examination of skin cells is also performed.

Blood tests can distinguish psoriatic arthritis from other types of arthritis. Rheumatoid arthritis , in particular, is diagnosed by the presence of a particular antibody present in the blood. That antibody is not present in the blood of patients with psoriatic arthritis.

Treatment

Age, general health, lifestyle, and the severity and location of symptoms influence the type of treatment used to reduce inflammation and decrease the rate at which new skin cells are produced. Because the course of this disease varies with each individual, doctors must experiment with or combine different treatments to find the most effective therapy for a particular patient.

Mild-moderate psoriasis

Steroid creams and ointments are commonly used to treat mild or moderate psoriasis, and steroids are

sometimes injected into the skin of patients with a limited number of lesions. In mid-1997, the United States Food and Drug Administration (FDA) approved the use of tazarotene (Tazorac) to treat mild-to-moderate plaque psoriasis. This water-based gel has chemical properties similar to vitamin A.

Brief daily doses of natural sunlight can significantly relieve symptoms. Sunburn has the opposite effect.

Moisturizers and bath oils can loosen scales, soften skin, and may eliminate the itch. So can adding a cup of oatmeal to a tub of bath water. Salicylic acid (an ingredient in aspirin ) can be used to remove dead skin or increase the effectiveness of other therapies.

Moderate psoriasis

Administered under medical supervision, ultraviolet light B (UVB) is used to control psoriasis that covers many areas of the body or that has not responded to topical preparations. Doctors combine UVB treatments with topical medications to treat some patients and sometimes prescribe home phototherapy, in which the patient administers his or her own UVB treatments.

Photochemotherapy (PUVA) is a medically supervised procedure that combines medication with exposure to ultraviolet light (UVA) to treat localized or widespread psoriasis. An individual with wide-spread psoriasis that has not responded to treatment may enroll in one of the day treatment programs conducted at special facilities throughout the United States. Psoriasis patients who participate in these intensive sessions are exposed to UVB and given other treatments for six to eight hours a day for two to four weeks.

Severe psoriasis

Methotrexate (MTX) can be given as a pill or as an injection to alleviate symptoms of severe psoriasis or psoriatic arthritis. Patients who take MTX must be carefully monitored to prevent liver damage.

Psoriatic arthritis can also be treated with non steroidal anti-inflammatory drugs (NSAID), like acetaminophen (Tylenol) or aspirin. Hot compresses and warm water soaks may also provide some relief for painful joints.

Other medications used to treat severe psoriasis include etrentinate (Tegison) and isotretinoin (Accutane), whose chemical properties are similar to those of vitamin A. Most effective in treating pustular or erythrodermic psoriasis, Tegison also relieves some symptoms of plaque psoriasis. Tegison can enhance the effectiveness of UVB or PUVA treatments and reduce the amount of exposure necessary.

QUESTIONS TO ASK YOUR DOCTOR

• Is it safe to use the pool at my gym during an outbreak?
• How safe are alternative treatments?

Accutane is a less effective psoriasis treatment than Tegison, but can cause many of the same side effects, including nosebleeds, inflammation of the eyes and lips, bone spurs, hair loss, and birth defects. Tegison is stored in the body for an unknown length of time, and should not be taken by a woman who is pregnant or planning to become pregnant. A woman should use reliable birth control while taking Accutane and for at least one month before and after her course of treatment.

Cyclosporin emulsion (Neoral) is used to treat stubborn cases of severe psoriasis. Cyclosporin is also used to prevent rejection of transplanted organs, and Neoral, approved by the FDA in 1997, should be particularly beneficial to psoriasis patients who are young children or African-Americans, or those who have diabetes.

Other conventional treatments for psoriasis include:

• Capsaicin (Capsicum frutecens), an ointment that can stop production of the chemical that causes the skin to become inflamed and halts the runaway production of new skin cells. Capsaicin is available without a prescription, but should be used under a doctor's supervision to prevent burns and skin damage.
• Hydrocortisone creams, topical ointments containing a form of vitamin D called calcitriol, and coal-tar shampoos and ointments can relieve symptoms. Hydrocortisone creams have been associated with such side effects as folliculitis (inflammation of the hair follicles), while coal-tar preparations have been associated with a heightened risk of skin cancer.

Nutrition/Dietetic concerns

No specific dietary regimens have been proven to eliminate the risk, or to lessen the severity of a bout with the illness. As with any immune disorder, a person's health and well-being can help in coping with the disease. Because medical research has been conducted that indicates psoriasis can cause nutritional deficiencies, according to the NPF citing a study done by a New York dermatologist Janet Prystowsky, M.D., Ph.D., it is important to compensate for those possible deficiencies—ensuring enough protein, folates (obtained in leafy green vegetables), iron, water, and calories to combat other health issues of an even more serious nature and maintaining optimal health. According to the NPF some people have been observed by their physicians to enjoy relief from outbreaks, or worsening the psoriasis, when they have lost weight. Consequently, many dermatologists advocate a healthy weight as a way to benefit their patients regarding psoriasis. Eliminating caffeine , alcohol, sugar, white flour and products containing gluten has also been shown to benefit people in dealing with their psoriasis. If using dietary supplements , an alternative approach many prefer perhaps in addition to their other treatments, it is always advised to check with a physician to determine whether the supplement or herbal remedy is safe or effective to use with other treatments the individual might be undergoing.

Therapy

Treatment options might include ultraviolet light therapy, either natural or artificial. In the cases of psoriatic arthritis, actual physical complications could arise when the regular use of hands or feet might be affected to perform even daily tasks. It is possible that physical or occupational therapy might be required to restore or maintain movement. For the active senior adult, a painful episode with psoriasis might limit regular exercise or recreational activity—but maintaining physical and emotional well-being while dealing with the stress of this disease, and its outbreaks, is crucial. For example, if meditation techniques, or even massage therapy help an individual to relax, and presents no aggravation to the condition, a physician might recommend such therapy.

Prognosis

Most cases of psoriasis can be controlled, and most people who have psoriasis can live normal lives.

Some people who have psoriasis are so self conscious and embarrassed about their appearance that they become depressed and withdrawn. The Social Security Administration grants disability benefits to about 400 psoriasis patients each year, and a comparable number die from complications of the disease.

KEY TERMS

Plaque psoriasis —Refers to the thick, red patches of skin that are covered with silvery, flaky scales, and represents the most common form of psoriasis.

Erythrodermic psoriasis —The least common form of psoriasis that can cause a rash over the entire body, and sometimes triggered by severe sunburn, corticosteroids, or inadequate management of other forms of psoriasis.

Prevention

A doctor should be notified if:

• psoriasis symptoms appear or reappear after treatment
• pustules erupt on the skin and the patient experiences fatigue, muscle aches, and fever
• unfamiliar, unexplained symptoms appear.

Caregiver concerns

Whether it is self-care or providing care for someone else, it is first important to be sensitive to the condition, both its physical and possible emotional effects. In addition to being painful or making a person uncomfortable, psoriasis can bring visible rashes and blisters that might be embarrassing or deemed unsightly. Avoiding the triggers for the disease when it is latent is the important first step in caring for a person. Helping that person maintain a healthy diet, assisting with daily baths that can eliminate scales or ease inflammation—taking care to avoid water that is too hot or soaps that are too harsh—and applying moisturizers are essential in care. If the person receiving care is taking medication for the condition, make sure to remind, or assist, that person to take it. Resources for support groups and education are available. Helping a person deal with the disease that way can be a way to prevent the emotional issues from interfering with treatment.

In October of 2006, the Journal of the American Medical Association reported that psoriasis increases the risks of having a heart attack . According to a report from the NPF, it was not only those who were being treated with methotrexate—a medication that put patients at the highest risk of contracting heart disease—but even those who had milder forms of the disease. In a person who is 60 or older, the risk of a person with severe psoriasis is 36 percent higher than of someone without it. That risk is lower than that of a 30-year old compared with peers whose risk is three times that of a person who does not have severe psoriasis—but as a caregiver , or with self-care, that statistic is worth investigating. Signs of heart problems, or suspected heart problems should be communicated with a physician.

Resources

BOOKS

Icon Health Publications. The Official Patient's Sourcebook on Psoriasis: Directory for the Internet Age. (Revised edition) San Diego: Icon Health Publications. 2005.

Langley, Richard G.B. Psoriasis: Everything You Need to Know (Your Personal Health Papaback). Richmond Hill, Ontario: Firefly Books. 2005.

PERIODICALS

“A connection between psoriasis and celiac disease suspected for some.” Psoriasis Advance. (July/August 2004)

“Determinants of quality of life in patients with psoriasis: a study from the U.S. population.” Journal of the American Academy of Dermatology. (Nov. 2004) 704–708.

“Traditional treatments have not fully met the need of psoriasis patients: results from a national survey.” Journal of the American Academy of Dermatology. (March 2005) 434–444.

OTHER

“Emollients and Psoriasis.” http://www.papaa.org.

“Psoriasis and Heart Disease.” http://www.psoriasis-cure-now.org.

“Psoriasis.” http://www.mayoclinic.com.

“Psoriasis.” http://www.nlm.nih.gov/medlineplus.

“Psoriasis.” http://www.psoriasis.org.

“Study linking increased risk of death to severe psoriasis a call to action.” http://www.psoriasis.org/news/press/2007/20071219_gelfand.php.

ORGANIZATIONS

National Psoriasis Foundation, 6600 SW 92nd Ave., Suite 300, Portland, OR, 97223-7195, 503-244-7404, 800-723-9166, 503-245-0626, [email protected], http://www.psoriasis.org.

The Psoriasis and Psoriatic Arthritis Alliance, Unit 3, Horseshoe Business Park, Lye Lane, Bricket Wood, St. Albans, Hertfordshire, United Kingdown, AL2 3TA, 0870–7703212, 0870–7703213, [email protected], http://www.papaa.org.

Jane Elizabeth Spehar

Psoriasis

Definition

Named for the Greek word psōra meaning "itch," psoriasis is a chronic, non-contagious disease characterized by inflamed lesions covered with silvery-white scabs of dead skin.

Description

Psoriasis, which affects at least four million Americans, is slightly more common in women than in men. Although the disease can develop at any time, 10-15% of all cases are diagnosed in children under 10, and the average age at the onset of symptoms is 28. Psoriasis is most common in fair-skinned people and extremely rare in dark-skinned individuals.

Normal skin cells mature and replace dead skin every 28-30 days. Psoriasis causes skin cells to mature in less than a week. Because the body can't shed old skin as rapidly as new cells are rising to the surface, raised patches of dead skin develop on the arms, back, chest, elbows, legs, nails, folds between the buttocks, and scalp.

Psoriasis is considered mild if it affects less than 5% of the surface of the body; moderate, if 5-30% of the skin is involved, and severe, if the disease affects more than 30% of the body surface.

Types of psoriasis

Dermatologists distinguish different forms of psoriasis according to what part of the body is affected, how severe symptoms are, how long they last, and the pattern formed by the scales.

PLAQUE PSORIASIS. Plaque psoriasis (psoriasis vulgaris), the most common form of the disease, is characterized by small, red bumps that enlarge, become inflamed, and form scales. The top scales flake off easily and often, but those beneath the surface of the skin clump together. Removing these scales exposes tender skin, which bleeds and causes the plaques (inflamed patches) to grow.

Plaque psoriasis can develop on any part of the body, but most often occurs on the elbows, knees, scalp, and trunk.

SCALP PSORIASIS. At least 50 of every 100 people who have any form of psoriasis have scalp psoriasis. This form of the disease is characterized by scale-capped plaques on the surface of the skull.

NAIL PSORIASIS. The first sign of nail psoriasis is usually pitting of the fingernails or toenails. Size, shape, and depth of the marks vary, and affected nails may thicken, yellow, or crumble. The skin around an affected nail is sometimes inflamed, and the nail may peel away from the nail bed.

GUTTATE PSORIASIS. Named for the Latin word gutta, which means "a drop," guttate psoriasis is characterized by small, red, drop-like dots that enlarge rapidly and may be somewhat scaly. Often found on the arms, legs, and trunk and sometimes in the scalp, guttate psoriasis can clear up without treatment or disappear and resurface in the form of plaque psoriasis.

PUSTULAR PSORIASIS. Pustular psoriasis usually occurs in adults. It is characterized by blister-like lesions filled with non-infectious pus and surrounded by reddened skin. Pustular psoriasis, which can be limited to one part of the body (localized) or can be widespread, may be the first symptom of psoriasis or develop in a patient with chronic plaque psoriasis.

Generalized pustular psoriasis is also known as Von Zumbusch pustular psoriasis. Widespread, acutely painful patches of inflamed skin develop suddenly. Pustules appear within a few hours, then dry and peel within two days.

Generalized pustular psoriasis can make life-threatening demands on the heart and kidneys.

Palomar-plantar pustulosis (PPP) generally appears between the ages of 20 and 60. PPP causes large pustules to form at the base of the thumb or on the sides of the heel. In time, the pustules turn brown and peel. The disease usually becomes much less active for a while after peeling.

Acrodermatitis continua of Hallopeau is a form of PPP characterized by painful, often disabling, lesions on the fingertips or the tips of the toes. The nails may become deformed, and the disease can damage bone in the affected area.

INVERSE PSORIASIS. Inverse psoriasis occurs in the armpits and groin, under the breasts, and in other areas where skin flexes or folds. This disease is characterized by smooth, inflamed lesions and can be debilitating.

ERYTHRODERMIC PSORIASIS. Characterized by severe scaling, itching, and pain that affects most of the body, erythrodermic psoriasis disrupts the body's chemical balance and can cause severe illness. This particularly inflammatory form of psoriasis can be the first sign of the disease, but often develops in patients with a history of plaque psoriasis.

PSORIATIC ARTHRITIS. About 10% of partients with psoriasis develop a complication called psoriatic arthritis. This type of arthritis can be slow to develop and mild, or it can develop rapidly. Symptoms of psoriatic arthritis include:

• joint discomfort, swelling, stiffness, or throbbing
• swelling in the toes and ankles
• pain in the digits, lower back, wrists, knees, and ankles
• eye inflammation or pink eye (conjunctivitis)

Causes and symptoms

The cause of psoriasis is unknown, but research suggests that an immune-system malfunction triggers the disease. Factors that increase the risk of developing psoriasis include:

• family history
• stress
• exposure to cold temperatures
• injury, illness, or infection
• steroids and other medications
• race

Trauma and certain bacteria may trigger psoriatic arthritis in patients with psoriasis.

Diagnosis

A complete medical history and examination of the skin, nails, and scalp are the basis for a diagnosis of psoriasis. In some cases, a microscopic examination of skin cells is also performed.

Blood tests can distinguish psoriatic arthritis from other types of arthritis. Rheumatoid arthritis, in particular, is diagnosed by the presence of a particular antibody present in the blood. That antibody is not present in the blood of patients with psoriatic arthritis.

Treatment

Age, general health, lifestyle, and the severity and location of symptoms influence the type of treatment used to reduce inflammation and decrease the rate at which new skin cells are produced. Because the course of this disease varies with each individual, doctors must experiment with or combine different treatments to find the most effective therapy for a particular patient.

Mild-moderate psoriasis

Steroid creams and ointments are commonly used to treat mild or moderate psoriasis, and steroids are sometimes injected into the skin of patients with a limited number of lesions. In mid-1997, the United States Food and Drug Administration (FDA) approved the use of tazarotene (Tazorac) to treat mild-to-moderate plaque psoriasis. This water-based gel has chemical properties similar to vitamin A.

Brief daily doses of natural sunlight can significantly relieve symptoms. Sunburn has the opposite effect.

Moisturizers and bath oils can loosen scales, soften skin, and may eliminate the itch. So can adding a cup of oatmeal to a tub of bath water. Salicylic acid (an ingredient in aspirin ) can be used to remove dead skin or increase the effectiveness of other therapies.

Moderate psoriasis

Administered under medical supervision, ultraviolet light B (UVB) is used to control psoriasis that covers many areas of the body or that has not responded to topical preparations. Doctors combine UVB treatments with topical medications to treat some patients and sometimes prescribe home phototherapy, in which the patient administers his or her own UVB treatments.

Photochemotherapy (PUVA) is a medically supervised procedure that combines medication with exposure to ultraviolet light (UVA) to treat localized or widespread psoriasis. An individual with widespread psoriasis that has not responded to treatment may enroll in one of the day treatment programs conducted at special facilities throughout the United States. Psoriasis patients who participate in these intensive sessions are exposed to UVB and given other treatments for six to eight hours a day for two to four weeks.

Severe psoriasis

Methotrexate (MTX) can be given as a pill or as an injection to alleviate symptoms of severe psoriasis or psoriatic arthritis. Patients who take MTX must be carefully monitored to prevent liver damage.

Psoriatic arthritis can also be treated with non steroidal anti-inflammatory drugs (NSAID), like acetaminophen (Tylenol) or aspirin. Hot compresses and warm water soaks may also provide some relief for painful joints.

Other medications used to treat severe psoriasis include etrentinate (Tegison) and isotretinoin (Accutane), whose chemical properties are similar to those of vitamin A. Most effective in treating pustular or erythrodermic psoriasis, Tegison also relieves some symptoms of plaque psoriasis. Tegison can enhance the effectiveness of UVB or PUVA treatments and reduce the amount of exposure necessary.

Accutane is a less effective psoriasis treatment than Tegison, but can cause many of the same side effects, including nosebleeds, inflammation of the eyes and lips, bone spurs, hair loss, and birth defects. Tegison is stored in the body for an unknown length of time, and should not be taken by a woman who is pregnant or planning to become pregnant. A woman should use reliable birth control while taking Accutane and for at least one month before and after her course of treatment.

Cyclosporin emulsion (Neoral) is used to treat stubborn cases of severe psoriasis. Cyclosporin is also used to prevent rejection of transplanted organs, and Neoral, approved by the FDA in 1997, should be particularly beneficial to psoriasis patients who are young children or African-Americans, or those who have diabetes.

Other conventional treatments for psoriasis include:

• Capsaicin (Capsicum frutecens ), an ointment that can stop production of the chemical that causes the skin to become inflamed and halts the runaway production of new skin cells. Capsaicin is available without a prescription, but should be used under a doctor's supervision to prevent burns and skin damage.
• Hydrocortisone creams, topical ointments containing a form of vitamin D called calcitriol, and coal-tar shampoos and ointments can relieve symptoms. Hydrocortisone creams have been associated with such side effects as folliculitis (inflammation of the hair follicles), while coal-tar preparations have been associated with a heightened risk of skin cancer.

Alternative treatment

Non-traditional psoriasis treatments include:

• Soaking in warm water and German chamomile (Matricaria recutita ) or bathing in warm salt water.
• Drinking as many as three cups a day of hot tea made with one or a combination of the following herbs: burdock (Arctium lappa ) root, dandelion (Taraxacum mongolicum ) root, Oregon grape (Mahonia aquifolium ), sarsaparilla (Smilax officinalis ), and balsam pear (Momardica charantia ).
• Taking two 500-mg capsules of evening primrose oil (Oenothera biennis ) a day. Pregnant women should not use evening primrose oil, and patients with liver disease or high cholesterol should use it only under a doctor's supervision.
• Eating a diet that includes plenty of fish, turkey, celery (for cleansing the kidneys), parsley, lettuce, lemons (for cleansing the liver), limes, fiber, and fruit and vegetable juices.
• Eating a diet that eliminates animal products high in saturated fats, since they promote inflammation.
• Drinking plenty of water (at least eight glasses) each day.
• Taking nutritional supplements including folic acid, lecithin, vitamin A (specific for the skin), vitamin E, selenium, and zinc.
• Regularly imagining clear, healthy skin.

Other helpful alternative approaches include identifying and eliminating food allergens from the diet, enhancing the fuction of the liver, augmenting the hydrochloric acid in the stomach, and completing a detoxification program. Constitutional homeopathic treatment, if properly prescribed, can also help resolve psoriasis.

Prognosis

Most cases of psoriasis can be controlled, and most people who have psoriasis can live normal lives.

Some people who have psoriasis are so self conscious and embarrassed about their appearance that they become depressed and withdrawn. The Social Security Administration grants disability benefits to about 400 psoriasis patients each year, and a comparable number die from complications of the disease.

KEY TERMS

Arthritis— An inflammation of joints.

Prevention

A doctor should be notified if:

• psoriasis symptoms appear or reappear after treatment

• pustules erupt on the skin and the patient experiences fatigue, muscle aches, and fever
• unfamiliar, unexplained symptoms appear.

Resources

ORGANIZATIONS

American Academy of Dermatology. 930 N. Meacham Road, P.O. Box 4014, Schaumburg, IL 60168-4014. (847) 330-0230. Fax: (847) 330-0050. 〈http://www.aad.org〉.

American Skin Association, Inc. 150 E. 58th St., 3rd floor, New York, NY 10155-0002. (212) 688-6547.

National Psoriasis Foundation. 6600 S.W. 92nd Ave., Suite 300, Portland, OR 97223. (800) 723-9166. 〈http://www.psoriasis.org〉.

Psoriasis

What Is Psoriasis?

What Causes Psoriasis?

What Does Psoriasis Look Like?

How Is Psoriasis Treated?

Living with Psoriasis

Resources

Psoriasis (so-RY-a-sis) is a long-lasting skin disease that causes patches of skin to become red, thickened, and covered with silvery-looking flakes.

KEYWORD

for searching the Internet and other reference sources

Skin disorders

What Is Psoriasis?

When the American writer John Updike wrote a book about his own life, titled Self-Consciousness, he spent a whole chapter describing his personal battle with a long-lasting skin disease known as psoriasis. Updike called the chapter, “At War with My Skin.” The word “psoriasis” comes from the Greek word for “to itch.” The disease causes patches of skin to become red, thickened, itchy, and covered with silvery flakes.

What Causes Psoriasis?

Two out of every 100 people in the United States have psoriasis. In some cases, the disease is too mild to notice. In other cases, it is severe enough to cover much of the body. The cause of psoriasis is still unknown. Scientists do know that the disease cannot be passed from one person to another. In other words, it is not possible to catch psoriasis from someone else who has it.

Recent research suggests that psoriasis may be due to a problem with the immune system*. The immune system includes a type of white blood cell called a T cell. Researchers now think that people with psoriasis may have a problem with the immune system that causes it to make too many T cells in the skin.

* immune system

fights germs and other foreign substances that enter the body.

People with psoriasis often notice that there are times when their skin gets worse, then gets better. The bad times, known as flare-ups, may be triggered by such things as climate changes, infections, stress, dry skin, and certain medicines. Flare-ups may also occur after the skin has been cut, scratched, rubbed, or sunburned. People whose relatives have psoriasis are more likely to also have it. Scientists are now studying families with psoriasis to try to find genes linked to the disease.

What Does Psoriasis Look Like?

Psoriasis causes patches of red, thickened skin with silvery flakes, most often on the scalp, elbows, knees, lower back, face, inside of the hands, and bottom of the feet. These patches are sometimes known as plaques (PLAKS). They may itch or burn, and the skin may crack. The disease also can affect the fingernails, toenails, and soft areas inside the mouth and genitals. About one out of 10 people with psoriasis gets psoriatic arthritis (so-ree-AT-ik ar-THRY-tis), a condition that causes pain, swelling, and stiffness of the joints (the places where bones meet).

How Is Psoriasis Treated?

A doctor usually identifies psoriasis by looking carefully at the skin, scalp, and nails. If the problem is psoriasis, the doctor can try various treatments that may clear up the skin for a time. The choice of treatment depends on a person’s age, health, and lifestyle and the severity of the psoriasis. No one treatment works for everyone, but most people can be helped by something. These are some of the treatment choices:

• Medicines put on the skin. Some creams, lotions, soaps, shampoos, and bath products created to treat psoriasis may be helpful. Some bath products and lotions may help loosen flakes and control itching, but they are usually not strong enough to clear up the skin.
• Treatments with light. Many people with psoriasis improve if they get sunlight every day in small amounts. To better control the light that reaches the skin, doctors sometimes use special lamps that give off ultraviolet (ul-tra-VY-o-let) rays, which are a part of sunlight. In some cases, the person also takes a medicine that makes the skin more sensitive to the ultraviolet light.
• Medicines taken by mouth. Some people with more severe psoriasis take medicines by mouth or in a shot.

Living with Psoriasis

Many people with psoriasis find that it helps to keep the skin moist. Lotions, oils, and petroleum jelly (Vaseline) are often useful for this purpose. During the winter months, heaters can make the air inside a house quite dry, so it may help to run a humidifier (hu-MID-i-fy-er), a machine that puts moisture back into the air. It is also a good idea for people with psoriasis to avoid getting harsh soaps and chemicals on their skin. In addition, they should protect their skin from injury by taking such steps as not wearing overly tight clothes or shaving with a dull razor.

See also

Arthritis

Resources

Pamphlets

American Academy of Dermatology. “Psoriasis.” To order, contact the American Academy of Dermatology, P.O. Box 681069, Schaumburg, IL 60168-1069, (888) 462-DERM. http://www.aad.org

National Institute of Arthritis and Musculoskeletal and Skin Diseases. “Questions and Answers About Psoriasis.” To order, contact the NIAMS Information Clearinghouse, 1 AMS Circle, Bethesda, MD 20892-3675, (301) 495-4484. http://www.nih.gov/niams

Organization

National Psoriasis Foundation, 6600 S.W. 92nd Avenue, Suite 300, Portland, OR 97223-7195, (503) 244-7404. A national group for people with psoriasis. The website includes a special section for children and teenagers. http://www.psoriasis.org