Health

Reactive arthritis gets its name from the fact that symptoms are triggered by some type of infection elsewhere in the body, although the arthritis may develop weeks or months after the original infection. 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). When all three problems — arthritis, eye inflammation, and urinary symptoms — occur together, the condition is called Reiter's syndrome.

Causes of reactive arthritis

Reactive arthritis and Reiter's syndrome 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.