|Notes on Psoriasis|
Leon H. Rottmann, Ph.D., Professor Emeritus, University of Nebraska-Lincoln
Sources: Information provided through John R. Luckason, M.D., Dermatologist, Omaha, NE. Selected references include: Managing Psoriasis, Dermatology Times, Nov 97, pp 21-84; Psoriasis Treatments, Dermatology Times, Nov 96, pp 14-22; New Horizons in the Management of Psoriasis, Vol. 61, No 2S, pp 7-44; Brochure on Psoriasis, American Academy of Dermatology, 1994.
The message on psoriasis: "Psoriasis is a T-cell-mediated, auto-immune, skin-specific disease. The therapy should be directed at disabling the excessive cell-mediated immunity that one finds within the psoriatic lesion." John J. Voorhees, M.D., Chief of Dermatology, University of Michigan, Ann Arbor. Several authors describe psoriasis as "the auto-immune wounding of the skin."
Psoriasis is a persistent skin disease that takes its name from the Greek word for "itch." In some cases, psoriasis is so mild that people don't even know that they have it. At the opposite extreme, severe psoriasis may cover large areas of the body and harbor a pustular form. Psoriasis cannot be passed from one person to another; it is more likely to occur in family blood lines. In the United States two out of every hundred people have psoriasis (four to five million people.) Approximately 150,000 new cases occur each year. Approximately 10 percent of psoriasis patients also have psoriatic arthritis; the percentage of celiac patients who may also have psoriasis is not known. It would appear that celiacs with acute infections, alcoholism, diabetes mellitus, arthritis and selected drug interactions may have a greater problem in the management of psoriasis and with the severity of the condition.
The agent that triggers the excessive response in the skin is not yet known. But its is known that antigen-presenting cells cause T-cells to become activated, releasing lymphokines and cytokines. This perpetuates a proliferation and activation of lymphocytes and provides a stimulation signal to the epidermis and keratinocytes to release cytokines, which perpetuate the process.
Simply - there appears to be an abnormality in the functioning of key white cells in the blood stream triggering inflammation in the skin. This causes the skin to shed itself too rapidly - every three to four days. People often notice new spots 10 to 14 days after that skin is cut, scratched, rubbed or sunburned. Psoriasis can also be activated by infections, such as strep throat, and by certain medications. Flare-ups sometimes occur in the winter, as a result of dry skin and lack of sunlight. Celiacs who report psoriasis also report having evaluations which indicate low absorption levels of vitamin D.
The disease is clearly a clinically and genetically heterogeneous disorder. Given the prevalence of psoriasis, it is not surprising that studies have found associations between this disease and more than one genetic locus. Good examples included the several studies of insulin-dependent diabetes mellitus patients in which more than 10 genetic loci have been identified. It is this genetic susceptibility in conjunction with environmental triggers which are thought to determine the clinical manifestation of psoriasis.
Psoriasis comes in many forms. Each differs in how bad it is, how long it lasts, where it is and in the shape and pattern of scales. The most common form begins with little red bumps. Gradually these grow larger and scales below the surface stick together. When they are removed, the tender, exposed skin bleeds. These small red areas then grow, sometimes becoming quite large.
Elbows, knees, groin and genitals, arms, legs, scalp and nails are often the areas most commonly affected by psoriasis. It will often appear in the same place on both sides of the body. Nails with psoriasis may have tiny pits on them. Nails may loosen, thicken or crumble. Inverse psoriasis occurs in the armpit, under the breast and in skin folds around the buttocks, groin and genitals. Guttate psoriasis usually affects children and young adults. It often shows up after a sore throat, (an upper respiratory or ear infection) wit many small, red, drop-like, scaly spots appearing on the skin. It typically clears up by itself in a few weeks with or without treatment.
Psoriasis patients with arthritis report that the arthritis is worse when the skin is involved. Sometimes the arthritis improves when the condition of the patient's skin improves. Celiac patients have reported a similar pattern: when the celiac disease is well-monitored, they may not be aware of any breaking out related to a potential psoriasis, when the celiac has a toxic reaction related to the ingestion of gluten, the itching and/or psoriasis may also again be activated.
Psoriasis is not established as an autoimmune disease simply because the autoantigen is not known. But there are lots of diseases thought to be autoimmune for which an antigen is not known. "The immune-driven process is the heart and soul of this disease," reports Enno Christophers, M.D., Director of Dermatology at the University of Kiel, Germany.
Dr. Christophers feels that an abnormality of a genetic allele, or a number of them, is likely to explain why the psoriasis patient's immune system recognizes antigens that are not either recognized or poorly recognized by other individuals. In a multifactorial, heterogeneous disease such as psoriasis, there may be more susceptibility genes participating to bring about that expression of the condition. Both Dr. Voorhees and Dr. Christophers classify psoriasis as an organ-specific autoimmune disease, such as multiple sclerosis, systemic sclerosis and Crohn's disease.
Physicians diagnosis psoriasis by examining the skin, scalp and nails. You may have thought flaky was only an adjective for piecrusts and croissants but with psoriasis you will learn that in actuality, it describes skin with psoriasis. Oftentimes, a laboratory procedure is needed which involves a skin biopsy which is then examined under a microscope for a definitive diagnosis.
The physician may prescribe medications to apply on the skin containing cortisone-like compounds, synthetic vitamin D, tar or anthralin. These may be used in combination with natural sunlight or ultraviolet light. Some patients may require oral medications, with or without light treatment. Sunlight exposure helps the majority of people with psoriasis but it must be used cautiously and with careful monitoring.
Just as there are many variants of psoriasis, there are many and varying treatment models for psoriasis. The celiac who may also have psoriasis is thought to do best staying inside medical treatment management and not get into mail order and over-the-counter (food and tea and rose oil) remedies even though they may come with highly-touted testimonials. Several new treatments are on the horizon, but are being reported with reserved optimism until long-term results are available--and, of course, an amenability of the treatment patterns to individual patients.
CSA Library Series
CSA Library Series is a collection of articles that pertain to celiac disease and dermatitis herpetiformis. Most of these articles have appeared in CSA’s quarterly newsletter, Lifeline, which all CSA members receive. Historic articles included in these resources may or may not include updated notes. Updated information indicated in red type. Articles represent the work of the author.