Other types of arthritis
| April 1, 2008
In-Depth Report
Other types of arthritis
Many other types of arthritis exist. The most common ones are discussed below.
Gout
Gout, a painful and potentially debilitating form of arthritis, has afflicted such famed figures as Benjamin Franklin and Henry VIII. Today it affects roughly two million Americans. This disorder develops after tiny, needle-like crystals of uric acid (a biological waste product) accumulate in joints, causing swelling and extreme sensitivity, sometimes to the point where even the slight touch of a sheet is unbearable. The same crystals may cause kidney stones if they accumulate in the kidneys.
Gout usually affects one joint at a time, most often the big toe, but sometimes a knee, ankle, wrist, foot, or finger. If gout persists for many years, uric acid crystals may collect in the joints or tendons and under the skin, forming whitish deposits known as tophi. About 90 percent of people with gout are men older than 40, and African American men are twice as likely as Caucasian men to be affected. Gout tends not to occur in women until at least 10 years after menopause.
Causes of gout
For many people, gout develops after a combination of factors contributes to the buildup of excessive levels of uric acid in the body. Abnormally high levels of uric acid may result from a diet that is rich in purines, chemicals that are broken down into uric acid by the body. Purines can be found in anchovies, nuts, and organ foods such as liver, kidney, and sweetbreads. Sometimes, for unknown reasons, the body will produce too much uric acid regardless of diet. Gout can also develop when the kidneys excrete too little uric acid, which can happen in people with some types of kidney disease and in those who drink too much alcohol. In addition, obesity or sudden weight gain can cause elevated levels of uric acid. Some medications, particularly diuretics, also contribute to high uric acid levels. People at risk for developing gout include those with a family history of the disease and those with hypertension, hyperlipidemia, or diabetes.
Symptoms of goutpain and swelling within a joint, especially the big toe often, an initial episode that occurs at night shiny red or purple skin around the affected joint extreme tenderness around the joint |
Diagnosing gout
To reach a diagnosis, your doctor will ask you about your diet, your medication use, your alcohol consumption, and whether you have a family history of gout. During a physical exam, your doctor will inspect your inflamed joints and look for tophi on your skin. Your doctor may also use a needle to withdraw a small fluid sample from your affected joint. This fluid will be examined under a microscope to determine whether uric acid crystals are present. Your doctor may also order a blood test to determine your uric acid level, but this test is not definitive because — for a variety of different reasons — many people without gout have an elevated uric acid level, and even in people with gout, the results may be normal.
Treating gout
Gout is usually treated with a two-prong medication strategy: The first goal is to ease attacks of joint pain and inflammation, while the second, longer-term goal is to decrease blood uric acid level and prevent further attacks.
Usually a doctor begins by prescribing a nonsteroidal anti-inflammatory drug (NSAID) to control pain and inflammation (see "NSAIDs"). Aspirin may raise your uric acid level; for this reason aspirin (and aspirin containing NSAIDs such as salsalate) is not a good NSAID choice to treat an attack of gout. However, many people take low dose aspirin to reduce the risk of heart attack, stroke or other serious health problems. If you've been instructed to take low dose aspirin, don't stop taking it without discussing it with your doctor.
If you cannot tolerate an NSAID or if these drugs are ineffective, your doctor may suggest a corticosteroid. Less often, high dose oral colchicine is prescribed, but be aware that this drug tends to cause unpleasant side effects (nausea, vomiting, cramps, diarrhea) and is not well tolerated in about 80 percent of people.
For people with attacks that respond poorly to therapy, involve multiple joints, or occur frequently, or when kidney stones or tophi are present, a second type of drug may be prescribed to prevent future gout attacks. It's important to keep taking this drug even after you feel better. The first choice is usually allopurinol (Aloprim, Zyloprim), which decreases your body's production of uric acid. Other options include probenecid (Benemid) and sulfinpyrazone (Anturane), which help the kidneys to eliminate uric acid. An investigational medication, febuxostat, is not yet approved by the FDA, but has shown promise as a potential new treatment for gout.
You can help prevent further attacks by avoiding diuretics (if your doctors agree), limiting your alcohol intake, drinking plenty of water, and maintaining a healthy weight. You may also want to reduce your consumption of foods that seem to trigger gout attacks, such as meat and certain types of seafood and vegetables — although many people find that strict dietary restrictions are of limited benefit.
Pseudogout
Pseudogout is a form of arthritis that occurs when a particular type of calcium crystal accumulates in the joints. As more of these crystals are deposited in the affected joint, they can cause a reaction that leads to severe pain and swelling. The swelling can be either short-term or long-term and occurs most frequently in the knee, although it can also affect the wrist, shoulder, ankle, elbow, or hand. The pain caused by pseudogout is sometimes so excruciating that it can incapacitate someone for days.
As its name suggests, the symptoms of pseudogout are similar to those of gout (see "Gout"). Pseudogout can also resemble osteoarthritis or rheumatoid arthritis. A correct diagnosis is vital, as untreated pseudogout can lead to joint degeneration and osteoarthritis. Pseudogout is most common in the elderly, occurring in about 3% of people in their 60s and as many as half of people in their 90s.
Causes of pseudogout
The cause of this condition is unknown. Because risk increases significantly with age, it is possible that the physical and chemical changes that accompany aging increase susceptibility to pseudogout. Certain medical conditions also make people more susceptible to pseudogout. These include an underactive thyroid (hypothyroidism), a genetic disorder of iron overload (hemochromatosis), or excessive blood levels of calcium (hypercalcemia). Pseudogout also can be triggered by joint injury, such as joint surgery or a sprain, or the stress of a medical illness. If the underlying condition causing pseudogout can be identified and treated, it may be possible to prevent future attacks. Frequently, however, there is no identifiable trigger.
Symptoms of pseudogoutpain, swelling, and stiffness around a single joint, especially the knee or wrist occasionally, more then one joint affected at a time fever, usually low-grade |
Diagnosing pseudogout
It may be difficult to diagnose pseudogout because it shares so many symptoms with gout, infection, and other causes of joint inflammation. In fact, pseudogout often occurs in people with other joint problems, such as osteoarthritis. Therefore, even when pseudogout is correctly identified, it is important to investigate whether there are other conditions present as well.
Your doctor may order an x-ray of the inflamed joint in order to look for calcium deposits in the cartilage, although these deposits are sometimes present in healthy elderly people who do not experience the swelling that characterizes pseudogout. To verify the presence of calcium crystals, your doctor may remove a small amount of fluid from the affected joint. This is done with a needle, after applying a numbing medication to the joint. This joint fluid is then analyzed for evidence of calcium crystals, inflammation, or infection. Your doctor may also order tests for other conditions that can trigger pseudogout, including tests of calcium and thyroid function.
Treating pseudogout
To combat joint pain and swelling, your doctor may prescribe NSAIDs such as indomethacin and naproxen, or may give you glucocorticoid injections to keep the swelling down (see "Corticosteroid injections"). Your doctor may also remove fluid from the inflamed joint, a procedure called aspiration, as this may help to ease the pressure and inflammation.
The combination of joint aspiration and medication usually eliminates symptoms within a few days, although the doctor may also recommend treatment with oral corticosteroids over a short period of time. Daily use of a low-dose NSAID or colchicine, a medicine that is also used in the treatment of gout, may help to prevent further attacks. Unfortunately, there is no treatment available that can dissolve the calcium crystal deposits, although the joint degeneration that often goes along with pseudogout may be slowed by treatments that decrease joint swelling. Occasionally, people with recurrent or chronic pseudogout may develop osteoarthritis. In this case, surgery (such as joint replacement) may be the only effective treatment.
Ankylosing spondylitis
Ankylosing spondylitis is a chronic, systemic inflammatory disease that may strike in the prime of life, often between the ages of 20 and 40. It's more common in men than in women. The disease develops as tendons attaching muscles to the spine become inflamed, causing pain and limiting movement. As ankylosing spondylitis progresses, vertebrae in the spinal column may fuse (see Figure 10). In its most advanced stages, the disease may affect joints in the lower back and upper buttocks and also cause inflammation or damage to the eyes, heart, and lungs.
Figure 10: X-ray of the spine
This x-ray shows a fused bamboo-like spine characteristic of ankylosing spondylitis. |
Causes of ankylosing spondylitis
Ankylosing spondylitis runs in some families. An unusually high percentage of people with ankylosing spondylitis — 96% in one study — carry the HLA-B27 gene, which occurs more commonly in white people than in other racial groups. A person who carries the HLA-B27 gene has only about a 1%–2% chance of developing ankylosing spondylitis. If a parent or sibling has the condition, however, experts estimate that the risk for a person with the gene rises to 10%–20%. Conversely, not having the gene is no guarantee of protection.
Symptoms of ankylosing spondylitisback pain and stiffness that develop gradually over weeks back pain and stiffness that persist for months discomfort that is most noticeable in the morning, but improves with exercise |
Diagnosing ankylosing spondylitis
Ankylosing spondylitis is one of the more difficult rheumatic diseases to diagnose early because the symptoms are similar to other causes of low back pain. It may take up to five years after the onset of symptoms for ankylosing spondylitis to show up on an x-ray. At first, x-rays will show that the margins of the sacroiliac joints appear indistinct. Later, the bones ankylose (or fuse) (see Figure 10).
Treating ankylosing spondylitis
Most people with ankylosing spondylitis can lead normal lives by using a combination of anti-inflammatory drugs and physical therapy. Your doctor may start by prescribing an NSAID such as indomethacin, but if this doesn't reduce the inflammation, a second choice is often a DMARD such as sulfasalazine or methotrexate. Several studies have demonstrated that anti-TNF agents are beneficial for ankylosing spondylitis. As they are FDA-approved for this condition, doctors are increasingly recommending anti-TNF drugs as a first choice of therapy . (See Appendix for more information about these drugs.)
If you develop ankylosing spondylitis, you can take steps to prevent spine deformity; in fact, such measures are an essential part of treatment. At least twice a day, try to practice stretching exercises that extend the spine, preferably after a hot shower has reduced stiffness. Rheumatologists recommend swimming as the best overall exercise because it does not stress the back as much as running or other weight-bearing exercises.
Reactive arthritis
Reactive arthritis is the more appropriate term for what doctors in the past called Reiter's syndrome.
Reactive arthritis gets its name from the fact that symptoms are triggered by some type of infection elsewhere in the body. The infection is most commonly in the intestinal tract (such as salmonella) or a sexually transmitted disease (such as Chlamydia). The arthritis may develop weeks or months after the original infection, well after the infection has been treated and is cured. When it does appear, symptoms may flare suddenly, causing pain and stiffness in joints, most typically in the wrists, knees, ankles, and feet.
About 40% of people with reactive arthritis develop conjunctivitis (eye inflammation), which is usually mild and transient. Some people have uveitis, a more serious eye inflammation that may also occur in ankylosing spondylitis. In addition, many people with reactive arthritis develop urinary symptoms due to inflammation of the urethra (the tube that carries urine from the bladder out of the body). Many people with reactive arthritis have the "classic" combination of all three problems — arthritis, eye inflammation, and urinary symptoms.
Symptoms of reactive arthritisfatigue and fever generalized muscle aching and joint pain low back pain radiating to buttocks or thighs discomfort aggravated by inactivity, eased by exercise arthritis that develops suddenly eye redness and discomfort in some people symptoms following an infection of the intestinal tract or a sexually transmitted disease |
Causes of reactive arthritis
Reactive arthritis may develop after infection with a sexually transmitted organism, such as Chlamydia, one of the primary bacteria that cause a genitourinary infection known as urethritis, once thought to occur almost exclusively in men. Now physicians recognize that women often have genitourinary infections that are initially silent, while men nearly always experience discharge, burning, and other overt symptoms.
Reactive arthritis can also be caused by gastrointestinal infection from bacteria such as Salmonella, Shigella, Campylobacter, or Yersinia, which may produce mild transient diarrhea or severe bloody diarrhea accompanied by vomiting. Often food or contaminated water is the source of these bacteria.
Although these infections are common, only certain people seem to be susceptible to developing reactive arthritis, and scientists believe there may be a genetic predisposition. Approximately 70% of white people with reactive arthritis have the HLA-B27 gene, compared with 7% of the general population.
Treating reactive arthritis
Physicians prescribe antibiotics to alleviate the underlying infection and add NSAIDs for the arthritis. DMARDs such as sulfasalazine or methotrexate may be prescribed for people with prolonged attacks. Relapses occur in about one-third of people.
Psoriatic arthritis
Psoriatic arthritis is a complication of psoriasis, a chronic skin disease that is characterized by bright pink or salmon-colored scales covering the knees, elbows, chest, back, or scalp. While most people with psoriasis do not develop arthritis, around 15% do. About 75% of people develop psoriatic arthritis only after the skin condition appears, although in some people the arthritis occurs before the skin condition.
Psoriatic arthritis usually develops between ages 20 and 50 and can affect any joint of the body. At least five variations of psoriatic arthritis exist, differentiated according to which joints are involved and whether both sides of the body are uniformly affected (such as one elbow or both elbows). When fingernails are affected by psoriasis, becoming pitted and ridged, the joints at the tips of the affected fingers are especially likely to develop arthritis. Psoriatic arthritis affects everyone differently, as symptoms and their intensity may vary and can also change within individuals as time passes. Psoriatic arthritis, like psoriasis, is lifelong and cannot be prevented.
Causes of psoriatic arthritis
Although the cause of psoriatic arthritis is unknown, it probably develops from a combination of genetic and environmental factors. An estimated 40% of people with psoriatic arthritis have a family history of either arthritis or psoriasis, suggesting some type of genetic predisposition.
It is also likely that certain genes are associated with different kinds of psoriatic arthritis. For instance, the gene HLA-B27 may contribute to psoriatic spondylitis, which affects the spine. Although most people with this gene do not develop psoriatic arthritis, it is found more often in people who develop this condition than in those who do not. Possible environmental factors that could trigger psoriatic arthritis in a genetically vulnerable person include infection and injury. For example, people with HIV may be more likely to develop this condition
Symptoms of psoriatic arthritismorning joint stiffness joint pain and inflammation, particularly in the fingers, toes, or spine pink or salmon scales on the scalp, knees, elbows, chest, or lower back pitting of fingernails or toenails |
Diagnosing psoriatic arthritis
Your doctor will ask about your symptoms and do a physical examination. Making a diagnosis may be difficult because symptoms of psoriatic arthritis so closely resemble those of other conditions, such as gout and rheumatoid arthritis. Even x-rays may not always be able to pinpoint psoriatic arthritis as the correct diagnosis. Given the challenges, some people may need to undergo further testing, including x-rays, blood tests, and skin biopsy (a procedure during which a small section of skin is removed for analysis). Your doctor may also remove a small amount of fluid from your inflamed joints in order to rule out other types of arthritis.
Treating psoriatic arthritis
Psoriatic arthritis need only be treated as symptoms arise. However, if psoriatic arthritis is left untreated during symptom flare-ups, it can cause permanent joint damage. Psoriatic arthritis affects each person differently. Although it is only a minor irritation for some, for as many as 25% of people who have it, this condition brings excruciating pain and severe joint damage that can lead to physical disability. Treatment enables most people with psoriatic arthritis to control their pain and to limit joint damage.
Treatment usually begins with taking NSAIDs such as ibuprofen or naproxen to relieve pain and inflammation. If these prove insufficient, your doctor may recommend that you take a DMARD such as methotrexate, which can also improve the psoriasis, or sulfasalazine. When these treatments do not work well, anti-TNF therapies may be particularly effective (see "Biologic response modifiers"). Corticosteroid injections can help to control severe inflammation but are used only occasionally, as they tend to be followed by a flare-up of psoriasis. If severe joint damage occurs, your doctor may recommend surgery to repair or replace those joints. To treat your psoriasis, your doctor may also recommend topical medications that can be applied to your skin or exposure to ultraviolet (UV) light, although these treatments will not help your arthritis. Exercise is also essential, as it helps to keep joints flexible and prevents muscle weakness and loss.
Enteropathic arthritis
Enteropathic arthritis develops in approximately 9%–20% of people with ulcerative colitis or Crohn's disease, which are types of inflammatory bowel disease. These disorders cause episodes of abdominal pain, diarrhea, and weight loss. When arthritis develops in people with ulcerative colitis or Crohn's disease, it usually affects multiple joints in the arms and legs. About 20% of people with enteropathic arthritis have sacroiliitis, an inflammation of the sacroiliac joints in the lowest region of the back.
What causes enteropathic arthritis
Studies show that people with enteropathic arthritis have a hereditary disposition to inflammatory bowel disease, but no specific gene has been discovered to account for this type of arthritis. Inflammatory bowel disease causes ulcers and microscopic abscesses in the colon (in ulcerative colitis) or throughout the intestinal tract (in Crohn's disease). Enteropathic arthritis may result from an immune response to intestinal bacteria that gain access to the body through an inflamed bowel.
Symptoms of enteropathic arthritisarthritis in multiple joints, usually the knees, ankles, elbows, and wrists, and sometimes in the spine, hips, or shoulders worsening of symptoms during inflammatory bowel disease flare-ups |
Diagnosing enteropathic arthritis
Your doctor will perform a physical examination and ask you about your symptoms and your ulcerative colitis or Crohn's disease. He or she may order imaging and blood tests (see "Diagnosing arthritis").
If you have ulcerative colitis, arthritis often appears during a colitis flare-up and disappears when bowel symptoms subside. It may be difficult to correctly diagnose the type of arthritis in someone with ulcerative colitis, however. Some actually suffer from ankylosing spondylitis, with symptoms that don't fluctuate with colitis symptoms. To further complicate matters, some people diagnosed with ankylosing spondylitis have asymptomatic inflammation of the small intestine, raising the possibility that their disease may actually be enteropathic arthritis.
Treatment of enteropathic arthritis
Physicians treat enteropathic arthritis with medications similar to those used in rheumatoid arthritis, including NSAIDs, sulfasalazine, methotrexate, and anti-TNF medications (see "Medications for rheumatoid arthritis").
Lyme disease and other infectious arthritis
Infectious arthritis, as indicated by its name, is caused by an infection with bacteria, viruses, or fungi. Infections usually spread to the joints from the site of origin by way of the bloodstream, so it may be difficult to determine where the infection started. Once the infection reaches the joint, it can cause warmth, pain, and swelling, sometimes accompanied by fever and chills. Occasionally, infection is introduced directly, as with a puncture wound or major injury.
Infectious arthritis due to bacteria most often affects the knee, although infections that are caused by viruses are most likely to affect small joints such as fingers or toes. People with other joint diseases, such as rheumatoid arthritis, are slightly more likely to develop infectious arthritis, although the overall frequency of infectious arthritis, even among people with existing joint problems, is relatively low.
Causes of infectious arthritis
Viruses are the most common cause of infectious arthritis, but bacterial infections tend to be the most serious.
Viral infections. Many viruses may trigger arthritis, including the viruses that cause colds and other respiratory infections, as well as more serious illnesses such as AIDS and hepatitis. Parvovirus, an infection common in young children, can cause arthritis in adults who are exposed to sick kids. Multiple joints can be affected at the same time, and the symptoms sometimes appear similar to those of rheumatoid arthritis. Most viral infections causing joint pain subside without treatment as the body's immune system eliminates the virus. However, chronic viral infections, such as HIV infection and some forms of viral hepatitis, can cause ongoing joint pain.
Bacterial infections. Lyme disease, which is caused by the bacterium Borrelia burgdorferi, is transmitted primarily through bites of deer ticks. An infected person may develop a large, round rash with a central, clear area known as a "bull's-eye," as well as fatigue and other flulike symptoms. But the symptoms may be subtle or mistaken for something else, so Lyme disease may not be diagnosed promptly. If Lyme disease goes untreated and advances, arthritis may develop. This type of arthritis usually affects one or both knees but can also affect other larger joints.
Arthritic joint pain also affects about a third of people with gonorrhea, a sexually transmitted bacterial infection. Staphylococcus bacteria, which can cause infections through cuts or breaks in the skin and through contaminated food, can be released in the bloodstream and spread to the knees and other joints, causing intense pain and swelling. If a staph infection is not treated promptly, it can cause serious joint damage within just a few days. Tuberculosis, a bacterial infection that usually affects the lungs, can cause arthritis in the spine and in other large joints, such as the knees or hips. Reactive arthritis and Reiter's syndrome are caused by infection with bacteria in the genitourinary or digestive tracts.
Symptoms of infectious arthritisjoint inflammation, pain, and stiffness symptoms typically in the knee, shoulder, ankle, finger, wrist, or hip joints fever and chills rash |
Diagnosing infectious arthritis
To help determine the infectious agent, your doctor may withdraw a small amount of fluid from the affected joint and have it analyzed. The doctor may also order blood and urine tests. While these tests are unable to pinpoint every infectious agent, blood tests that measure antibodies against some of the more chronic viral diseases, such as hepatitis B, hepatitis C, and HIV, are often helpful.
If you are a woman and a sexually transmitted disease is suspected, the doctor may perform a pelvic exam. If you are a man, your doctor may swab your penis and test your urine.
Treating infectious arthritis
Any infection should be treated as soon as possible in order to prevent permanent damage. If joint pain and complications have developed, these will be treated separately. You may need to briefly immobilize your affected joint while recovering from the infection. But it's best to become active again as soon as you are able, because exercise and physical therapy can help you regain your strength and mobility.
Treating viral infections. Viral infections do not carry the same risk of joint damage as bacterial infections do, but the infection itself may be harder to treat, as viruses do not respond to antibiotics. Some viral infections, such as HIV or hepatitis C infection, can be treated with antiviral therapy. For other types of viral infections, taking aspirin or ibuprofen can help reduce pain and swelling while the infection runs its course.
Treating bacterial infections. If you have a bacterial infection, your doctor will probably start with an antibiotic. If the infection is advanced or if joint damage has already occurred, the doctor may recommend that you be hospitalized so that your affected joint can be drained (which may require minor surgery) and given adequate rest, and so that you can receive antibiotics intravenously. If your joint is seriously damaged, you may need surgery in order to remove damaged tissue and reconstruct the joint.
Preventing infectious arthritis
It's much better for your health if you can prevent infectious arthritis from developing at all. That means trying to avoid infections, especially those that can cause permanent joint damage. You can reduce exposure to viruses by washing your hands frequently, especially during cold and flu seasons. You can protect yourself from sexually transmitted bacteria and viruses by practicing safe sex. Promptly cleaning wounds and cooking food thoroughly will reduce your exposure to staph infections. To avoid Lyme disease, take measures to avoid tick bites. For example, use tick repellant when walking in the woods or tall grass, wear long-sleeved shirts, and tuck long pants into socks.
Review Date: 2008-04-01
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