Psoriasis is a skin condition that affects about 1 in 50 Americans. It is characterized by exessive itchiness, sometimes causing a person to scratch until they bleed, as well patches of thickened skin which sheds. Despite the discomfort and debilitating effect on the life of a person living with psoriasis, there is an additional concern. A joint condition known as psoriatic arthritis can develop in as many as 3 in 10 people who have psoriasis.
What Happens In Psoriatic Arthritis
Psoriatic arthritis is inflammation of the joints that is associated with the skin disease, psoriasis. However, not every person with psoriasis develops psoriatic arthritis. Similarly not every person who develops psoriatic arthritis has psoriasis previously. The cause of psoriatic arthritis has not been conclusively identified and the same applies to psoriasis. However, it appears to be an interaction of genetic, environmental and immunologic factors.
Read more on psoriatic arthritis.
Most people who develop psoriasis have a family history of the condition. Studies have indicated that about 4 in 10 people with psoriasis or psoriatic arthritis has a first degree relative with one of these conditions. Certain genes have been identified that may increase susceptibility to developing psoriasis and psoriatic arthritis. Certain environmental factors may also increase the risk and possibly serve as triggers but do not cause psoriasis or psoriatic arthritis.
The mechanism behind psoriasis and psoriatic arthritis appears to be linked to the immune system. It is believed that the immune system produces autoantibodies which then attach to healthy tissue. These antibodies direct the immune system’s activity towards the tissues it attaches to. The immune defenses then prematurely become active and target the body’s own tissue. Therefore it is referred to as an autoimmune disease.
In psoriasis the immune activity is against the skin tissue. In psoriatic arthritis the immune system appears to attack the joint. This is similar to rheumatoid arthritis where there is joint inflammation due to abnormal immune activity against the joint tissue, like the joint lining (synovium). Psoriatic arthritis may go through periods of remission and flareups as is the case with psoriasis.
How To Spot Psoriatic Arthritis
People with psoriasis need to be the most cautious and attentive to the warning signs of psoriatic arthritis. Only about 15% of people with psoriatic arthritis do not have a history of arthritis. Early diagnosis and treatment of psoriatic arthritis is always advisable.
Proper management may not only ease the debilitating effects of psoriatic arthritis but it may possibly help to minimize thr risk of complications. Arthritis mutilans is one such complication and is a severe form of arthritis that is very painful, may lead to destruction of the bone and lead to disability.
However, psoriatic arthritis does not only result in joint symptoms. The abnormal immune activity can also extend to other parts of the body causing a host of other signs and symptoms (extra-articular manifestations). These other symptoms may not be associated with psoriatic arthritis at the outset. It is therefore important that psoriatic arthritis is monitored by a medical professional on a regular basis.
Since psoriasis is present or was present in most people with psoriatic arthritis, this skin disease should be considered among the signs of psoriatic arthritis. The rash in psoriasis is typically red and the skin is very dry, cracking and scaling. There may also be bleeding, which is often caused by excessive scratching. Itching is usually severe and there may also be a burning sensation.
Read more on psoriasis.
Joint pain is known as arthralgia and common in most types of arthritis. Pain is usually worse after exertion of the affected joint but can also occur at rest. It typically correlates with the swelling. In psoriatic arthritis, the pain is most often felt in the finger and toe joints. It can either be one-sided or affect both sides simultaneously. There is also tenderness on and around the affected joint.
Joint stiffness is a major symptom of psoriatic arthritis as is the case with most types of arthritis. It usually correlates with the degree of pain and swelling of the joints. However, sometimes stiffness and pain can occur on its own. Various factors may worsen the stiffness, such as long periods of inactivity. Many people with psoriatic arthritis report morning stiffness, similar to rheumatoid arthritis, that gradually eases with activity.
Swollen Fingers and Toes
Swelling of the joints is another common sign of psoriatic arthritis. However, the swelling may extend beyond the joint in the fingers and toes which gives rise to sausage-shaped digits (dactylitis). Sometimes the swelling may involve the entire hand or foot. It should not be confused with deformities of the joints which can arise in time. Nodules that are seen in rheumatoid arthritis (RA) are usually not present in psoriatic arthritis.
Heel and Back Pain
In psoriatic arthritis, other areas may be affected like where tendons attach to bones. The heel is one of the commonly involved parts. Similarly, the joints of the spine may also be affected which gives rise to neck and back pain. Other areas that are not commonly affected in most types of arthritis but may be involved in psoriatic arthritis are the hips and chest joints.
Another non-specific sign of psoriatic arthritis that does not involve the joints is fatigue. The unexplained and severe tiredness is unrelated to other factors like poor nutrition and insufficient sleep. Severe itching in psoriasis can also affect sleep which may lead to fatigue and this also needs to be excluded. Sometimes fatigue, joint pain and joint stiffness are the only symptoms of psoriatic arthritis apart from the skin rash seen in psoriasis.
Certain eye problems may arise in psoriatic arthritis and many people do not associate these eye conditiosn with the arthritis. However, these eye problems can occur in as many as 30% of people with psoriatic arthritis. These eye conditions that may occur include conjunctivitis (inflammation of the conjunctiva) which is the most common, conjunctokeratitis (conjunctiva and cornea), uveitis (uvea), iritis (iris) and scleritis (sclera).