Anyone who is susceptible to developing food poisoning can also develop reactive arthritis.  However, reactive arthritis usually affects people between the ages of 20 and 50.

Not every person who gets an infection that can cause reactive syndrome will also develop the disease. Some people may have a genetic predisposition and therefore a higher risk of developing reactive syndrome. Just as we inherit our hair colour and blood type from our parents, we also inherit our tissue type. The tissue typing system is the Human Lymphocyte Antigen (HLA) system. One of the tissue types, HLA-B27, is found in only a small percentage of the broad population. Approximately 6% to 10% of the Caucasian population has HLA-B27; it is even more rare to find HLA-B27 in people of African descent. Having the HLA-B27 tissue type seems to increase a person's risk of developing reactive arthritis after a bacterial infection, and may also increase the risk that reactive arthritis will not quickly resolve. Approximately 50% of reactive arthritis patients are HLA-B27 positive.

• If you have reactive arthritis you will probably develop the warning signs within a few weeks after you've had an infection. 
• The infection may have been food poisoning or another illness of the intestine. It could also have been chlamydia (pronounced clam-i-dee-a), which is a disease passed on by an infected person during sex. Reactive arthritis cannot be passed from one person to another.
• Stiffness, pain and swelling in a joint that seems to have come on for no reason. The area may also be red and hot.
• There may be pain in the lower back, or on the heel or bottom of the foot.
• Pain and stiffness may be worse in the morning.
• The eyes may feel sore or sensitive to sunlight.
• Sores may appear in the mouth or on the genitals. These may be painful or painless.

They may also appear after an infection of the sexually transmitted disease chlamydia. Reactive arthritis is itself not contagious or sexually transmitted.

If you have reactive arthritis you will probably experience redness, heat, stiffness, pain or swelling in a joint that has not been injured. Usually only a single joint is involved. Stiffness and pain may be worse in the morning. 

Most often the inflammation occurs in the lower limbs (knees, ankles, toes). You may also have lower back pain resulting from involvement of the sacroiliac (pronounced sac-ro-il-ee-ac) joints - the joints at the base of the spine where the spine joins the pelvis. Ongoing joint problems may result in stiff joints and weak muscles and it could become difficult to fully straighten the joints.

Problems may develop with other body systems such as your tendons, skin and eyes. Some people have pain in the heel where the Achilles (pronounced a-kill-ees) tendon attaches to the bone, or underneath the foot where the tendons supporting the arch of the foot attach to the heel. 

Women may develop irritation of the cervix but may not have symptoms of it. Urethritis (pronounced yur-reeth-rite-iss) may develop and cause painful or difficult urination. Painful or painless skin ulcers sometimes appear in the mouth, on or the penis or vagina. You may also have problems with your eyes, including pain or sensitivity to sunlight. When inflammation occurs in any of these areas, this is a form of reactive arthritis called Reiter's syndrome.

• Certain types of bacteria cause reactive arthritis. If you have reactive arthritis one of these types of bacteria may have already made you sick.
• The bacteria that cause reactive arthritis are some of those that cause food poisoning or other illness of the intestine. The names of these bacteria are Salmonella, Shigella, Campylobacter and Yersinia
• The bacteria that cause the disease chlamydia can also lead to reactive arthritis.
• After the bacteria cause you to get sick they can travel through your body to other areas, where they then cause inflammation.
• Reactive arthritis cannot be passed from one person to another.

Diagnosis may be difficult as there is no specific test that confirms reactive arthritis is present.  Your doctor will probably perform a physical examination and order other tests such as x-rays and blood tests. One test called an ESR (erythrocyte sedimentation rate) measures the level of red blood cells that are settling in the muscle. The erythrocyte sedimentation rate (ESR) is often high in people with reactive arthritis.  If you have reactive arthritis you may also have anaemia. This is a condition of the blood that can cause you to look pale, and feel weak, sleepy and dizzy.

Other tests your doctor may perform include tests of your stool (feces), or the fluids and tissues of your urethra or joints. About half of patients with reactive arthritis have a positive HLA-B27 test. This suggests a genetic predisposition to reactive arthritis but it is not always an indication of the disease. 

In many cases reactive arthritis goes away on its own within a few days or a few weeks. Some cases may take up to four months before they completely resolve. Other people have recurrent attacks. However, given treatment most people with reactive arthritis manage well. Your active involvement in developing your treatment plan is essential. 

Medicine

The bacterial infections that cause reactive arthritis may require treatment with antibiotics. If the preceding infection is one that can be transmitted sexually, it is common for sexual partners to be treated with antibiotics as well. Reactive arthritis itself is not sexually transmitted and is not contagious.

NSAIDs reduce pain when taken at a low dose, and relieve inflammation when taken at a higher dose. NSAIDs such as ibuprofen (Motrin IB, Advil, etc.) can be purchased without a prescription. Examples of NSAIDs that require a prescription include Naprosyn, Relafen, Indocid, Voltaren, Feldene, and Clinoril. The various NSAIDs, if taken in full doses, usually have the same levels of anti-inflammatory effect. However, different individuals may experience greater relief from one medication than another. A common NSAID, ASA (found in Aspirin, Anacin, etc.) is not used to treat the joint problems associated with reactive arthritis.

Taking more than one NSAID at a time increases the possibility of side effects, particularly stomach problems such as heartburn, ulcers and bleeding. People taking these medications should consider taking something to protect the stomach, such as misoprostol (Cytotec).

For severe pain and inflammation, doctors can inject a powerful anti-inflammatory drug, called a corticosteroid, directly into the affected joint. Cortisone is a steroid that reduces inflammation and swelling. It is a hormone naturally produced by the body. Corticosteroids are man-made drugs that closely resemble cortisone. An injection can provide almost immediate relief for a tender, swollen and inflamed joint. However, this treatment can only be used rarely, since corticosteroids can weaken the cartilage and remove the minerals from (and therefore weaken) the bone, resulting in further joint weakness.

Disease modifying anti-rheumatic drugs (DMARDs) may be prescribed when inflammation continues for more than a few months or when many joints are inflamed. DMARDs target the processes causing the inflammation, but do not reverse permanent joint damage. The most common of them are gold salts, methotrexate, sulfasalazine, hydroxychloroquinine, chloroquinine and azathioprine. DMARDs are often given in addition to other medications such as NSAIDs. They usually take a few months to make a difference in the inflammation. Side effects may include mouth sores, diarrhea and nausea. More serious side effects, monitored through regular blood and urine tests, include liver damage, and excessive lowering of the white blood cell count (increasing susceptibility to certain infections) and platelet count (affecting blood clotting). 

Exercise

Muscles and the other tissues that hold joints together weaken when they aren't moved enough, so the joint loses its shape and function. Moderate stretching exercises will help relieve pain and keep the muscles and tendons around the affected joint more flexible and strong. Low-impact exercises like swimming, walking, water aerobics and stationary bicycling can all reduce pain while maintaining your strength and flexibility. Always consult your doctor before beginning an exercise program.

Heat/Cold

Heat or cold application can provide temporary relief of pain. Heat helps to reduce pain and stiffness by relaxing aching muscles and increasing circulation to the area. There is some concern that heat may worsen the symptoms in an already inflamed joint.  Cold helps numb the area by constricting the blood vessels and blocking nerve impulses in the joint. Applying ice or cold packs appears to decrease inflammation and therefore is the method of choice when joints are inflamed.

Protect Your Joints

Protecting your joints means using them in ways that avoid excess stress. Benefits include less pain and greater ease in doing tasks. Three main techniques to protect your joints are:

Along with the physical symptoms of arthritis, many people experience feelings of helplessness and depression. Learning daily living strategies to manage your arthritis gives you a greater feeling of control and a more positive outlook. To get the best results, people affected by arthritis need to form close ties with their doctors and therapists, and become full partners in their treatment. From our perspective, it's all part of 'living well with arthritis.' There are several resources you can use in finding out how best to manage your own arthritis. Here are a few:

• The Arthritis Self-Management Program (ASMP) is a unique self-help program offered by The Arthritis Society to help you better control and manage your arthritis.
• The Open Forum within this Web site is an opportunity to discuss and share information with other visitors - people who, through their own experiences, may be able to offer some useful insights.

Of course, there are many other valuable resources for people with arthritis. If you're unclear about where to look for help, be sure to call The Arthritis Society at 1-800-321-1433.