In 5-10% of those with psoriasis, arthritis also appears. In most cases the psoriasis will precede the arthritis, sometimes by many years. When arthritis symptoms occur with psoriasis, it is called psoriatic arthritis (PsA). In these cases, the joints at the end of the fingers are most commonly affected causing inflammation and pain, but other joints like the wrists, knees and ankles can also become involved. This is usually accompanied by symptoms of the fingernails and toes, ranging from small pits in the nails to nearly complete destruction and crumbling as seen in reactive arthritis or fungal infections. Affecting men and women equally, about 10% to 30% of people with psoriasis develop psoriatic arthritis. Psoriatic arthritis may develop at any age, but usually affects people between the ages of 30 and 50. While the cause is not known, genetic factors, along with the immune system, infection, and physical trauma likely play a role in determining who will develop the disorder.
As many as 40% of people with psoriatic arthritis have a family history of skin or joint disease. Having a parent with psoriasis triples the chance of getting psoriasis yourself and thus increases the chance of developing psoriatic arthritis.
There are five types of psoriatic arthritis:
- Symmetric Psoriatic Arthritis: Symmetric arthritis affects the same joints -- usually in multiple matching pairs -- on opposite sides of the body. Symmetric arthritis can be disabling, causing varying degrees of progressive, destructive disease and loss of function in 50% of people with this type of arthritis. Symmetric arthritis resembles rheumatoid arthritis.
- Asymmetric Psoriatic Arthritis: Asymmetric arthritis typically involves one to three joints in the body -- large or small -- such as the knee, hip, or one or several fingers. Asymmetric arthritis does not affect matching pairs of joints on opposite sides of the body.
- Distal Interphalangeal Predominant (DIP): Distal interphalangeal predominant psoriatic arthritis involves primarily the small joints in the fingers and toes closest to the nail. DIP is sometimes confused with osteoarthritis, a chronic disease that causes the deterioration of joint cartilage and bone as well as bone spurs at the joints.
- Spondylitis: Spondylitis affects the spinal column and may cause inflammation and stiffness in the neck, lower back, spinal vertebrae, or sacroiliac region (pelvic area), making motion difficult. Spondylitis also can attack connective tissue, such as ligaments, or cause arthritic disease in the joints of the arms, hips, legs or feet.
- Arthritis Mutilans: Arthritis mutilans is a severe, deforming, and destructive form of psoriatic arthritis that primarily affects the small joints in the fingers and toes closest to the nail. This leads to lost function of the involved joints. It also is frequently associated with lower back and neck pain. Fortunately, this type of psoriatic arthritis is rare.
Psoriasis is a skin condition marked by a rapid buildup of rough, dry, dead skin cells that form thick scales. Arthritis causes pain and stiffness in your joints. Both are autoimmune problems - disorders that occur when your body's immune system, which normally fights harmful organisms such as viruses and bacteria, begins to attack healthy cells and tissue. The abnormal immune response causes inflammation in your joints as well as the overproduction of skin cells.
It's not entirely clear why the immune system turns on healthy tissue, but it seems likely that both genetic and environmental factors play a role. Many people with psoriatic arthritis have a close relative, such as a parent or sibling, with the disease, and researchers have discovered certain genetic markers that appear to be associated with psoriatic arthritis.
Having a family member with psoriatic arthritis doesn't necessarily mean you'll develop the disease, but it does mean you have a greater tendency to do so. Physical trauma or something in the environment - such as a viral or bacterial infection - may trigger psoriatic arthritis in people with an inherited tendency.
A substance called tumor necrosis factor (TNF), which causes inflammation in rheumatoid arthritis, appears to play a large role in psoriatic arthritis as well. People with psoriatic arthritis have high levels of TNF in both their joints and skin.
Certain factors may trigger psoriasis, including the following:
- Injury to the skin: Injury to the skin has been associated with plaque psoriasis. For example, a skin infection, skin inflammation, or even excessive scratching can trigger psoriasis.
- Sunlight: Most people generally consider sunlight to be beneficial for their psoriasis. However, a small minority find that strong sunlight aggravates their symptoms. A bad sunburn may worsen psoriasis.
- Streptococcal infections: Some evidence suggests that streptococcal infections may cause a type of plaque psoriasis. These bacterial infections have been shown to cause guttate psoriasis, a type of psoriasis that looks like small red drops on the skin.
- HIV: Psoriasis typically worsens after an individual has been infected with HIV. However, psoriasis often becomes less active in advanced HIV infection.
- Drugs: A number of medications may aggravate psoriasis. Some examples are as follows:
- Lithium: Drug used to treat bipolar disorder
- Beta-blockers: Drugs used to treat high blood pressure
- Antimalarials: Drugs used to treat malaria
- NSAIDs: Drugs, such as ibuprofen (Motrin and Advil) or naproxen (Aleve), used to reduce pain or inflammation
- Emotional stress: Many people see an increase in their psoriasis when emotional stress is increased.
- Smoking: Cigarette smokers have an increased risk of chronic plaque psoriasis.
- Alcohol: Alcohol is considered a risk factor for psoriasis, particularly in young to middle-aged men.
- Hormone changes: The severity of psoriasis may fluctuate with hormonal changes. Disease frequency peaks during puberty and menopause. A pregnant woman's symptoms are more likely to improve than worsen during her pregnancy, if any changes occur at all. In contrast, symptoms are more likely to flare in the period after childbirth, if any changes occur at all.
X-rays. These can help pinpoint changes in the joints that occur in psoriatic arthritis but not in other arthritic conditions.
Joint fluid test. In this test, your doctor removes a small sample of fluid from one of your joints - often the knee - for analysis in a laboratory. Uric acid crystals in your joint fluid may indicate that you have gout, rather than psoriatic arthritis.
Sed rate. This blood test checks your erythrocyte sedimentation rate (ESR), commonly known as the sed rate, by measuring how far from the top of a glass tube your red blood cells fall in a given time. Generally, the blood cells fall faster and farther - that is, the sed rate increases - when inflammation is present. But because many conditions can cause inflammation in the body, including many forms of arthritis and other rheumatic diseases, an elevated sed rate alone can't confirm the presence of psoriatic arthritis.
Rheumatoid factor (RF). RF is an antibody - a protein made by the immune system - that's often present in the blood of people with rheumatoid arthritis, but not in the blood of people with psoriatic arthritis. For that reason, this test can help your doctor distinguish between the two conditions.
The symptoms of psoriasis include scaly red patches appearing anywhere on the body, but often on the scalp, elbows, knees and lower end of the backbone. In psoriatic arthritis, the skin condition is accompanied by arthritis symptoms. See below for a list of the main symptoms:-
- As mentioned, the scaly patches on the skin caused by psoriasis.
- Pain and swelling in the fingers or toes, sometimes the swelling causing a "sausage" appearance.
- Small indentations, lifting and /or discoloration of the fingernails or toenails.
- Pain and swelling in the joints.
- Pain and stiffness of the spine, especially after prolonged inactivity.
- Inflammatory eye conditions of the eye such as iritis or conjunctivitis which can cause redness, pain, blurred vision and sensitivity to light.
A common treatment regimen for all the spondyloarthropathies (ankylosing spondylitis, reactive arthritis, psoriatic arthritis, enteropathic arthritis, and undifferentiated spondyloarthropathy) involves medication, exercise and possibly physical therapy, good posture practices, and other treatment options such as applying heat/cold to help relax muscles and reduce joint pain. In severe cases of ankylosing spondylitis, surgery may also be an option.
Depending on the type of spondyloarthritis, there may be some variation in treatment. For example, in psoriatic arthritis, both the skin component and joint component must be treated. In enteropathic arthritis (spondylitis/arthritis associated with inflammatory bowel disease such as Crohn's or ulcerative colitis), medications may need to be adjusted so the gastrointestinal component of the disease is not exacerbated.
Very often, a rheumatologist will be the one to outline a treatment plan, but other professionals may also be able involved in your care.
NSAIDs (nonsteroidal anti-inflammatory drugs) are still the cornerstone of treatment and the first stage of medication in treating the pain and stiffness associated with spondylitis. However, NSAIDs can cause significant side effects, in particular, damage to the gastrointestinal tract.
When NSAIDs are not enough, the next stage of medications, (also known as second line medications), are sometimes called disease modifying anti-rheumatic drugs (DMARDS). This group of medications include: Sulfasalazine, Methotrexate and Corticosteroids.
The most recent and most promising medications for treating ankylosing spondylitis are the biologics, or TNF Blockers. These drugs have been shown to be highly effective in treating not only the arthritis of the joints, but also the spinal arthritis. Included in this group are Enbrel, Remicade, Humira and Simponi.
Exercise in an integral part of any spondylitis management program. Regular daily exercises can help create better posture and flexibility as well as help lessen pain.
A properly trained physical therapist with experience in helping those with ankylosing spondylitis can be a valuable guide in regard to exercise.
Practicing good posture techniques will also help avoid some of the complications of spondylitis including stiffness and flexion deformities / kyphosis (downward curvature) of the spine.
Applying heat to stiff joints and tight muscles can help reduce pain and soreness. Applying cold to inflamed areas can help reduce swelling. Hot baths and showers can also help provide relief.
In severe cases of ankylosing spondylitis, surgery can be an option in the form of joint replacements, particularly in the knees and hips. Surgical correction is also possible for those with severe flexion deformities (severe downward curvature) of the spine, particularly in the neck, although this procedure is considered risky.
Other Symptom Management Tools
Alternative treatments such as massage and using a TENS unit (electrical stimulators for pain) can also aide in pain relief. Maintaining a healthy body weight and balanced diet can also aide in treatment.