Psoriasis is a common skin disease that causes dry, red, scaly patches that are sometimes itchy and painful. Any part of the body may be affected, but the scalp, elbows, knees and torso are most common. Besides the skin discomfort and potential disfigurement, psoriasis can be physically disabling, especially if it involves the hands, feet, or face.
Although uncommon in children, psoriasis affects about 2 to 3 percent of the U.S. population, men and women equally, all races, with an average age of 30 years. The disease is lifelong and may clear and flare up without reason. It does however, tend to worsen with age and for women, may worsen, stay the same, or clear up during pregnancy.
What causes psoriasis?
The exact cause is unknown, but it is believed to be an inherited abnormality of the immune system, leading to inflammation of the skin and joints. In about one-third of cases, a form of arthritis called “psoriatic arthritis” is associated with the skin disease. The symptoms are similar to rheumatoid arthritis with morning stiffness.
Psoriasis is not contagious. There are triggers that either bring it out for the first time or cause flare ups. These triggers include:
- Emotional stress such as grieving after a loss
- Injury to the skin, including surgery, and sunburns
- Reactions to specific drugs, such as beta-blockers used for hypertension and lithium
- Certain types of infections, especially viral and streptococcal sore throats
How is psoriasis treated?
Treatment for psoriasis depends on how extensive the disease is, as well as which body areas are involved. Severity is roughly defined as mild, moderate, and severe based on estimates of body surface area of involvement. However, involvement of facial areas, hands and feet, and genitalia, may cause such emotional and functional impairment that they may be considered severe.
Mild cases, defined as involving less than 5% of the body skin surface, are treated with lubrication of the skin with over-the-counter creams and ointments and natural sunlight. Creams containing coal tar and salicylic acid can also be helpful in relieving itch.
Mild-moderate cases, 5-10% body surface area, are treated with combinations of a variety of potent prescription topical creams and ointments, including corticosteroids, synthetic vitamin D, and vitamin A derivatives.
Moderate to severe cases (greater than 10% body surface area) are often treated with ultraviolet light called narrow band UVB or PUVA. This treatment, also known as “phototherapy” is given 1 to 3 times per week in the office and may take up to 30 exposures to produce clearing. After this, the frequency of treatment is reduced to a lower maintenance level.
What is the difference between UVB and UVA?
UVB or ultraviolet B light is short wave energy from either the sun or man-made lamps. We mainly associate UVB with causing sunburns, however, one small portion of the UVB spectrum was discovered to be the healing ray for rash of psoriasis. That ray is called the “Narrow-Band,” and special fluorescent lamps were developed to deliver only that specific ray which causes very little sunburn and virtually no tanning, neither of which are beneficial for psoriasis. We can deliver the narrow band UVB rays to the entire body surface in a full body cabinet for the more severe cases, or by a specially developed laser for treatment of more localized resistant skin lesions. Excellent results can be achieved with both methods.
UVA or ultraviolet A light is long wave energy from either the sun or man-made lamps. UVA is most closely associated with tanning and increased skin cancer risk. The longer the wavelength of ultraviolet light, the deeper the penetration of the energy into the skin. Tanning salons use UVA lamps, but we do not recommend them for the treatment of psoriasis. We have adapted a method of delivering UVA to the thickened skin of palms and soles by soaking the skin in a dilute solution of a plant-derived chemical called Psoralen followed by exposure to UVA rays in a specially adapted cabinet.
In this way, there is no internal exposure to the drug, and exposure to the light is reduced to a few minutes with very good results. The combination of the Psoralen soak and the UVA light is called PUVA.
What else is there for psoriasis?
For patients who are unable to make frequent office visits, or those who may have a high risk for skin cancer, there are some prescription pills, which have been approved for psoriasis for over 20 years. These drugs, methotrexate, acitretin, and cyclosporine, reduce inflammation and slow down skin cell growth. Patients treated with these medications have to be monitored closely by their experienced doctor for many possible side effects.
Are there any new medications for psoriasis?
The latest medications for psoriasis and psoriatic arthritis are called “biologics.” Injected directly into the body weekly (or less often), biologics are made up of proteins and antibodies. A few examples include Enbrel, Humira, Stelara, and Remicade. The pills listed above and these more sophisticated (and expensive) injectable biologic treatments are very effective at improving most patients’ skin and joints, but they do not provide the cure, which still remains elusive at this time.
Is there anything else psoriasis sufferers can do to help their skin?
While there are different levels of psoriasis, it is important, with any condition, to maintain a low saturated fat, high fish intake or fish oil supplemented diet, exercise regularly, and prohibit smoking. Excess alcohol intake reduces effectiveness of psoriasis treatments and may cause more side effects of some of the drugs. Obesity and cigarette smoking are associated with more severe forms of psoriasis. A recent journal article suggested that severe psoriasis may be an independent risk factor for heart attacks at a younger age compared to the general population. While the results need to be confirmed by additional studies, it gives psoriasis sufferers more motivation to adopt a healthy lifestyle.
Charles Camisa, M.D. is a board certified dermatologist. He authored the “Handbook on Psoriasis, Second Edition” published by Blackwell in 2005. He has also written many papers and book chapters which you can view on the Publications page of this website. Dr. Camisa is a member of the American Academy of Dermatology, National Psoriasis Foundation, and Dermatology Foundation. Currently, he specializes in all forms of psoriasis, lichen planus, pemphigoid, pemphigus, lupus of the skin, skin cancer, lymphoma of the skin, as well as mucous membrane disease of the mouth and lips.
For more information on psoriasis and other autoimmune diseases of the skin contact Dr. Charles Camisa at the Camisa Psoriasis Center of Riverchase Dermatology and Cosmetic Surgery. Fort Myers: 239-437-8810 , Cape Coral: 239-443-1500 and Downtown Naples: 239-216-4337.