Reactive arthritis is precipitated by antecedent gastrointestinal and genitourinary infections and manifests as an asymmetric sterile oligoarthritis, typically of the lower extremities. It is frequently associated with enthesitis. Extra-articular manifestations are common and include urethritis, conjunctivitis, uveitis, and mucocutaneous lesions. Reactive arthritis occurs most commonly in young men and is associated with HLA-B27 in 80% of white patients and 50–60% of blacks.
“Reactive arthritis, formerly called Reiter’s syndrome, is a type of arthritis that occurs as a ‘reaction’ to a bacterial infection in another part of the body. The most common types of infection that can lead to reactive arthritis are sexually transmissible infections and infections of the digestive system (usually as a result of food poisoning).”
Symptoms and Signs
Most cases of reactive arthritis develop within 1–4 weeks after either a gastrointestinal infection (usually with Shigella, Salmonella, Yersinia, or Campylobacter) or a sexually transmitted infection (with Chlamydia trachomatis or perhaps Ureaplasma urealyticum). Whether the inciting infection is sexually transmitted or dysenteric does not affect the subsequent manifestations but does influence the gender ratio: The ratio is 1:1 after enteric infections but 9:1 with male predominance after sexually transmitted infections.
Synovial fluid from affected joints is culture-negative. A clinically indistinguishable syndrome can occur without an apparent antecedent infection, suggesting that subclinical infection can precipitate reactive arthritis or that there are other, as yet unrecognized, triggers.
The arthritis is most commonly asymmetric and frequently involves the large weight-bearing joints (chiefly the knee and ankle); sacroiliitis or ankylosing spondylitis is observed in at least 20% of patients, especially after frequent recurrences.
Systemic symptoms including fever and weight loss are common at the onset of disease.
The mucocutaneous lesions may include balanitis, stomatitis, and keratoderma blennorrhagicum, indistinguishable from pustular psoriasis. Involvement of the fingernails in reactive arthritis also mimics psoriatic changes. When present, conjunctivitis is mild and occurs early in the disease course.
Anterior uveitis, which can develop at any time in HLA-B27-positive patients, is a more clinically significant ocular complication.
Carditis and aortic regurgitation may occur. While most signs of the disease disappear within days or weeks, the arthritis may persist for several months or become chronic.
Recurrences involving any combination of the clinical manifestations are common and are sometimes followed by permanent sequelae, especially in the joints (eg, articular destruction).
Radiographic signs of permanent or progressive joint disease may be seen in the sacroiliac as well as the peripheral joints.
Gonococcal arthritis can initially mimic reactive arthritis, but the marked improvement after 24–48 hours of antibiotic administration and the culture results distinguish the two disorders. Rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis must also be considered. By causing similar oral, ocular, and joint lesions, Behçet disease may also mimic reactive arthritis. The oral lesions of reactive arthritis, however, are typically painless, in contrast to those of Behçet disease. HIV is not more common in sexually active men with reactive arthritis.
NSAIDs have been the mainstay of therapy. Antibiotics given at the time of a nongonococcal sexually transmitted infection reduce the chance that the individual will develop this disorder. For chronic reactive arthritis associated with chlamydial infection, combination antibiotics taken for 6 months are more effective than placebo. Patients who do not respond to NSAIDs may respond to sulfasalazine, 1000 mg orally twice daily, or to methotrexate, 7.5–20 mg orally per week. For those patients with recent-onset disease that is refractory to NSAIDs and these DMARDs, anti-TNF agents, which are effective in the other spondyloarthropathies, may be effective.