*More than skin deep*

Although psoriasis has long been known as a skin disease, doctors now regard it as systemic and affecting other organs.

Prof. Michael David (photo credit: Courtesy)
Prof. Michael David
(photo credit: Courtesy)
Psoriasis – the chronic inflammatory disease of the skin that causes scaling, itch and redness on various parts of the body and affects more than 125 million people worldwide – is no longer considered only a dermatological condition.
Affecting around three percent of Israelis of all ages, psoriasis has been recognized as a relapsing/remitting systemic disease that may be connected to a variety of internal organs, has genetic links and results from an uncontrolled immune response.
Its name comes from the Greek for “itching condition,” and it has been known since ancient times.
World Psoriasis Awareness Day was marked globally at the end of last month, and the Israel Psoriasis Association held various events at the Dead Sea and elsewhere so that the public would understand that it is not contagious and that treatments are improving. The association lobbies toward the recognition of innovative and unlimited treatments, negotiates special prices for hotel stays at the Dead Sea, helps finance treatments at the resort area for those who can’t afford them, runs a summer camp for children suffering from the condition, holds conferences and provides up-to-date information on psoriasis.
The voluntary organization, established in the early 1970s, can be accessed (in Hebrew, English, Russian and Arabic) at www.psoriasis.
org.il. In addition, the association publishes a newsletter mailed to all of its members, and a lawyer who specializes in medical issues provides preliminary pro bono legal advice.
The association can be reached at (03) 624-7611.
For the occasion of the annual awareness day, The Jerusalem Post interviewed one of the country’s most experienced dermatologists and specialists in psoriasis, Prof.
Michael David, until his retirement three years ago chairman of dermatology department of the Rabin Medical Center-Beilinson Campus in Petah Tikva and of the Sackler Faculty of Medicine at Tel Aviv University.
He remains active with a private dermatology practice and also performs clinical research in his field at Beilinson.
David was born in Aden in Yemen and came to Israel in 1949 at the age of five. He grew up in Tel Aviv and studied medicine at Jerusalem’s Hebrew University Medical Faculty as part of the Israel Defense Forces academic program. He served as an IDF physician for a while and then left, but he returned during the Yom Kippur War, after which he studied his specialty at Beilinson. In 1993, he became chairman of the department.
Asked why he went into dermatology, David said: “It’s a very physical specialty, in which you touch the patient. It also gives a lot of satisfaction, because you can diagnose disease usually just by looking at the skin. I worked very hard and didn’t think about the long hours.”
His wife is a retired nurse, and his three adult children are in occupational therapy, social work and law.
IN HEALTHY skin, David explained, epidermal cells grow and replace the outer layers of the skin as they shed about once a month. Psoriasis develops when the immune system mistakes a normal skin cell for foreign invaders such as a bacterium or virus and sends out the wrong signals, that cause overproduction of new skin cells.
The rate of psoriasis among Israelis ranges between 2.2% to 3.5%, depending on their origins and habits, according to David. “It is rarer in China, where the prevalence is only 0.5%, and in Africans, and more common – between 5% and 7% – in Caucasians in Scandinavia and northern Europe. Women and men are equally at risk of getting it.
But, he added, there are also environmental triggers such as stress, tonsillitis, streptococcal infections an certain drugs such as beta blockers, lithium (for manic depression), anti-inflammation medications and others. Smoking and consuming too much alcohol can very often trigger the appearance of psoriasis. It appears for the first time at any age, but the most common is between 16 and 30 years. David added that it occurs more often in people with celiac disease, hypertension, diabetes and high cholesterol levels.
“We checked 1,000 psoriasis patients who were hospitalized over the years at our hospital, and compared to a control group, we find that the first group were more likely to have chronic metabolic diseases. So today, more researchers regard psoriasis not only as a skin disease but a systemic one,” the dermatologist noted. “When I come across younger people with it, I tell them they are at higher risk for metabolic diseases like diabetes and recommend that they change their lifestyles by exercising and eating a more healthy diet, without junk food,” he said.
“If they are obese, they should also consider bariatric surgery, as the stomach-shortening or -narrowing technique can bring about a dramatic reduction in psoriasis,” David noted. “There was almost no psoriasis in concentration camp inmates during the Holocaust because they were very thin, I have been told.”
There is also a slightly higher risk of lymphoma and leukemia (blood cancers) among people with psoriasis.
Patients with advanced HIV/ AIDS often develop the disease as well. The rates of gastroenterological conditions such as Crohn’s disease and ulcerative colitis are higher in psoriasis patients.
Fortunately, most sufferers have a mild condition, with localized patches of red and scaly skin. Only a minority have the lesions all over the whole body. About nine in 10 psoriasis cases are of the plaque type (psoriasis vulgaris), which shows up as redand- silvery white scaly patches on the upper layer of the skin. Skin cells quickly grow at these plaque sites, which are most often on the elbows and knees, but are also common on the scalp, soles of the feet, palms of the hands, and genitals. Even fingernails and toenails are often affected, with pitting.
In addition, inflammation of the joints – known as psoriatic arthritis – affects up to a third of patients with the plaque type, David said. This involves inflammation of the joints and surrounding connective tissue, especially affecting the joints of the fingers and toes. This can result in a sausage-shaped swelling of the fingers and toes and can also affect the hips, knees, spine and sacroiliac joint.
Other, less common types include inverse (flexural) psoriasis, in which the lesion appears as smooth, inflamed patches of skin, especially in the folds of the skin, between the thigh and groin, armpits, between the buttocks and under the breasts.
Napkin psoriasis is a subtype of psoriasis common in infants who have red papules (lesions) with silver scale in the diaper area that may extend to the torso or limbs. Guttate psoriasis is characterized by numerous small, scaly, red or pink teardrop-shaped lesions over large areas of the body.
Oral psoriasis is very rare. In seborrheic- like psoriasis, there are red plaques with greasy scales on the scalp, forehead, skin folds next to the nose, skin surrounding the mouth and skin on the chest above the breastbone.
While the causes of psoriasis are not fully understood, it is as yet incurable. When it is severe and disfiguring, it can also cause psychological and social problems, anxiety and depression. The semi-retired dermatologist said that about a third of psoriasis patients report a family history of the disease. If there is one identical twin with it, the other has a 70 percent risk of developing it as well; if a non-identical twin gets it, the other has a 20% risk. This indicates the dual genetic and environmental causes of the disease.
EARLY THIS year, David was chairman of a committee of the National Dermatology Council on setting new guidelines for treatment of psoriasis.
The majority of patients who have mild psoriasis are given creams (topical agents) such as corticosteroids, for about eight weeks, but they cannot be taken for long periods because of side effects. Retinoids and coal tar, which are also sometimes prescribed, have not proven to be of much use. Moisturizers and emollients such as mineral oil and petroleum jelly help get rid of existing scales. Topical agents are typically used for mild disease, and when they are combined with vitamin D, they can be more helpful.
Dead Sea resorts are known around the world for balneotherapy (climatotherapy) – gradual exposure over a period of weeks to the ultraviolet light of the sun. Because it’s at the lowest place on Earth, with 400 meters more atmosphere than in most locations, the majority of the harmful rays of the sun are filtered out, allowing exposure to sun without the risk of skin cancer, said David, who has done research on the UV effects at the Dead Sea on psoriasis.
“The Dead Sea psoriasis season is from April to October, and many patients achieve full remission, but it lasts only for several months. It is not a permanent cure.”
David noted that there are other places, such as Iceland and the Canary Islands, where such therapy is available, but there is no place as good as the Dead Sea for the purpose.
“The health funds’ supplementary health insurance plans help subsidize Dead Sea treatment, and many medical tourists come from as far as Russia and Germany to get treatment. It’s also a vacation that improves their condition by reducing stress. It also helps asthma patients.”
PUVA is phototherapy treatment (using artificial light) for psoriasis and various other skin conditions, with the drug psoralen taken orally or applied to the skin to sensitize it before UV exposure. When patients are far from the Dead Sea, they may use special ultraviolet A lamps to treat the disease, which works by reducing the speedy production of cells in the skin. But David discourages the use of sunbeds, as they pose a serious risk of skin cancer.
The dermatologist added that a number of new biological drugs have been developed for treating psoriasis and are gradually entering the market. These contain proteins that interfere with the immune process that causes the plaques.
“The biologicals created a new era. Very potent drugs are injected into the patient. Four such drugs have been approved by the Health Ministry for marketing. They are 70% effective, and sometimes they have an effect even for years, but in some cases, the condition returns in weeks or months. There is no cure.”
Most of the biologicals, he added, have to be injected because if swallowed, they would be destroyed by the digestive system. Two more drugs, apremilast and antijak1, are in the pipeline. Another new biological drug, soon to be introduced, is know generically as secukinumab; given once a week and then once monthly, it has been successful in 50% to 90% of patients, but is not a cure.
These medications, only some of which are in the health basket, are used for more serious cases. Their ending in the letters MAB represents monoclonal antibodies; these target molecules called cytokines, which cells use to send inflammatory signals to one another. Several monoclonal antibody drugs target cytokines, the molecules that cells use to send inflammatory signals to each other, and can relieve psoriasis.
Apremilast, used for the treatment of moderate-to-severe cases of the most common type of psoriasis, has been approved by the FDA after clinical trials were carried out at Mount Sinai Medical Center’s Icahn School of Medicine. It is the first oral drug for the condition to be approved in decades.
“But I don’t believe that psoriasis will be completely wiped out in the foreseeable future,” concluded David. “There will still be psoriasis patients, but dermatologists will be offering great improvement in treatment.”