Psoriatic Arthritis
What is Psoriatic Arthritis?
Psoriatic arthritis is an inflammation around the joints that occurs in people with the skin condition - psoriasis. Psoriatic arthritis can be referred to as PsA and the symptoms may resemble rheumatoid arthritis. Typically the affected joints are stiff and sometimes tender or swollen. According to the National Psoriasis Foundation, psoriatic arthritis occurs in close to 1/3 of people with skin psoriasis.
A unique feature of psoriatic arthritis is its variability: it may occur in one joint for a short period of time; it may occur in one or two joints for a day or two then migrate to other joints; several joints could become tender or swollen for months or even years; and in the extreme case, arthritis mutilans - the joints of the fingers and toes can become completely destroyed in a few years or less.
Fingers and toes are the most frequently affected but any joint including: wrists, elbows, shoulders, neck, ankles, knees, hips, spine, and ribs can be affected.
What Causes Psoriatic Arthritis?
Like psoriasis of the skin, psoriatic arthritis is a misdirection of the immune system. The area of the body attacked by the immune cells is the enthesium - the point where a ligament or tendon attaches to bone. No one knows why the enthesium becomes inflamed. It may be that a minor injury caused by a strained enthesium activates the psoriatic arthritis similar to the activation of skin psoriasis by injury to the skin
Genetics of Psoriatic Arthritis
We know less about the genetics of psoriatic arthritis than we do about psoriasis but like psoriasis, it takes three key components to bring about psoriatic arthritis: a genetic susceptibility to psoriasis and psoriatic arthritis, a trigger, and an immune response. As with skin psoriasis, we do not know all the genes involved, we do not know what the triggers are, and we are only beginning to understand the details of the immune response.
How Did I Get Here?
The typical story of psoriatic arthritis starts with the skin. Our first case study is of a 43 year old patient of Dr. Kim Papp. When she was 16, Janet noticed red, itchy, and scaly patches on her scalp. By the time she was 23, she had a few patches of psoriasis on her elbows that would clear in the summer. Janet sees Dr. Kim Papp regularly for the management of her psoriasis and she uses lotions and shampoos to treat her scalp.
When Janet was 27, she noticed her fingers getting stiff for a few hours every morning and sometimes she would have a sore wrist or a sore finger even if she did not do anything. In the beginning, her symptoms were not too bad but when Janet turned 30, the swelling and tenderness became more severe and more persistent. Janet found it difficult to open jars or hold onto a pen. One of her finger joints became crooked and would not fully straighten. Janet found relief after taking a NSAID and receiving a steroid injection for one joint. The relief lasted a few months and she continues to see Dr. Papp for her psoriatic arthritis and the management of her psoriasis.
What Happens if I Don't Do Anything about My Psoriatic Arthritis?
When the pain and swelling is minor, lasts for a short time, or affects only a few joints, we don't believe too much will happen and it is not usually a cause for concern. The old expression "the worse it is the worse it is" is very true of psoriatic arthritis. The more joints that are affected, the more rapid the onset of the joint pain, or the more joints that are tender or swollen, the more likely the psoriatic arthritis will progress and cause joint damage.
Several of Dr. Papp's psoriasis patients will have a few tender or stiff joints for a few days every few months. Usually, these patients take acetaminophen or ibuprofen to alleviate their discomfort. Quite often they will take nothing.
If you have a number of joints affected by stiffness, swelling, or tenderness, you are more likely to have damage to the joints caused by the psoriatic arthritis. Psoriatic arthritis can be deceptive and even if you don't have significant joint pain, the joint destruction can continue to occur.
What Are My Treatment Options for Psoriatic Arthritis?
For minor psoriatic arthritis symptoms, taking acetaminophen, ibuprofen, or another NSAID (non-steroidal anti-inflammatory drug) from time-to-time may be all you ever need.
Occasionally, steroids are injected into joints to reduce the swelling and pain. Medications which can be helpful for more severe cases include methotrexate, prednisone, and tumor necrosis factor (TNF)-antagonist biologics. Of the previously listed therapies, only the TNF-antagonist biologics reduce the progressive joint destruction in some people. Examples of these medications are: adalimumab (Humira®), etanercept (Enbrel®), infliximab (Remicade®), and golimumab (Simponi®).
Our second case study is about one of Dr. Kim Papp's psoriasis patients named Doug. Doug has had psoriasis on his scalp for 30 years. One day Doug visited Dr. Papp's clinic with a slightly tender, swollen index finger. The swelling presented in only one joint on the index finger and Doug felt it was tender. Within a few weeks the tenderness was gone but the swelling remained. The joint became a hard lump and fused. While the finger joint was swollen and tender Doug took a NSAID (non-steroidal anti-inflammatory drug) to relieve the pain. Had the joint become more affected, he would have had a steroid injection into the joint. Doug no longer has pain in his finger joint and he continues to see Dr. Papp for the management of his psoriasis.
A great deal of research is underway to understand psoriatic arthritis and to discover and develop new therapies. There are many clinical studies being conducted by PMR researchers. We are all working towards new and better treatment for psoriatic arthritis.
In 1992, Dr. Kim Papp, established a clinical research centre located in Kitchener-Waterloo, Ontario. To learn more about Dr. Papp's research and ongoing studies for psoriatic arthritis visit: ResearchTrials.org - K. Papp Clinical Research.
For more information on psoriatic arthritis please visit:
ResearchTrials.org: Psoriatic Arthritis
National Psoriasis Foundation: Psoriasis.org
American College of Rheumatology: Rheumatology.org
