Reactive arthritis is associated with an infectious agent causing an aseptic inflammation in joints and other organs. Classic disease is associated with three manifestations , urethritis (inflammation of the lower urinary tract) arthritis, and conjunctivitis. Reactive arthritis is the most common cause of arthritis in young men. The lower extremity joints and the lower spine are most commonly affected. About 1 % of nongonococcal urethritis patients develop reactive arthritis. The syndrome develops in up to 15% of gastrointestinal infections secondary to Shigella, Salmonella, Campylobacter, and Yersinia.
What are the Symptoms of Reactive Arthritis?
Reactive arthritis is associated with HLA-B27in 60%to 80%. The classic patient with reactive arthritis is a young man about 25 years old who develops conjunctivitis (pink eye with crusted lids) and urethritis (painful urination). Within two to three weeks, predominantly lower extremity arthritis appears. In some individuals, arthritis is the only manifestation of reactive arthritis. Back pain in the lumbosacral area is a frequent symptom in 30% of individuals. As opposed to ankylosing spondylitis, sacroiliac pain may be unilateral. Involvement of the upper portions of the spine occurs less commonly than sacroiliitis. Women tend to have more upper spine involvement than men. Attachments of tendons to bones (enthesis) can be inflamed near the heel involving the Achilles tendon or plantar fascia.
How is Reactive Arthritis Diagnosed?
Reactive arthritis refers to an inflammatory joint disease that follows an infection elsewhere in the body without microbial invasion of the joint space. The list of infectious agents include Salmonella, Shigella, Yersinia, Campylobacter, Chlamydia, Neisseria gonorrhoea3, streptococci,, and Giardia. Not all patients with venereal infections are symptomatic. Patients with reactive arthritis are distinguished from other spondyloarthropathies by the development of peripheral arthritis soon after urethritis or cervicitis, and/or conjunctivitis. Back pain is present in the sacroiliac area in about 30%. Radiographs may show unilateral or bilateral sacroiliitis. HLA-B27 is positive in 80% of reactive arthritis patients.
How is Reactive Arthritis Treated?
Initial treatment involves addressing the underlying infection with antibiotics. Acute arthritis is initially treated with nonsteroidal anti-inflammatory drugs. Corticosteroids are less effective in reactive arthritis than other inflammatory arthropathies. Disease of longer duration is treated with disease-modifying rheumatic drugs, or less frequently, tumor necrosis inhibitors. TNF inhibitors used in clinical trials include adalimumab, infliximab and etarnercept.
The course of the illness is unpredictable. A self-limited illness, lasting 3 months to 1 year, occurs in 30% to 40% of patients. Another 30% to 50% develop a relapsing pattern of illness with periods of complete remission. The final 10% to 25% develop chronic, unremitting disease associated with significant disability.