Reactive Arthritis

What is reactive arthritis?

Reactive Arthritis is a form of arthritis that develops in reaction to an infectious agent, such as bacteria, usually in the bowel or genital areas. Those developing the illness experience pain, swelling and stiffness, usually in larger joints, particularly the lower limbs, as well as the spine and ligaments. Typically the immune system readjusts its response to the infection and the condition ultimately goes away. However, reactive arthritis can last many months, even a few years, and, if prolonged, requires medical treatment.

Reactive Arthritis is a self‐limiting form of arthritis that develops in response to an infectious agent. Depending on the infectious agent itself and the individual’s genetic predisposition (background), the illness also can be associated with other symptoms including conjunctivitis (a redness and irritation of the outer layer of the eye called the conjunctiva), urethritis or cervicitis (eye redness or discharge from the penis or cervix), genital ulcers which may or may not be painful, and/or a skin rash on the palms of the hands or soles of the feet.

Although many infections, including viruses, can result in a reactive arthritis, the term usually applies to symptoms occurring after an infection of the bowel (caused by the germs Campylobacter, Salmonella, Shigella and Yersinia) or genitals (caused by Chlamydia trachomatis).

What causes reactive arthritis?

No one is entirely sure of the relationship between the bacteria and the cause of the arthritis. Clearly, the genetic predisposition to react to these specific bacteria with an arthritis illness must exist. However, the joints themselves are not actually infected. Rather, they are inflamed as a result of these bacteria triggering the immune system. In reactive arthritis, typically the immune system readjusts this response and the condition ultimately goes away.

Who gets reactive arthritis?

About 10 – 20 percent of people experiencing bowel and/or genital infections will get reactive arthritis, typically those whose genetic profile includes the presence of antigens called HLAB27. Most of these individuals, usually males between 20 and 50 years of age, will have a self‐limiting disease. However, 15% will face recurrence of the arthritis if re‐exposed to infection, or chronic arthritis. This is more likely to occur if the bacterium triggering the illness is Chlamydia trachomatis, a common sexually‐transmitted disease. Changes in the function of the immune system can also influence this illness. For instance, infection with the HIV/AIDS virus increases the risk of getting reactive arthritis.