Successful treatment of reactive arthritis with a humanized anti–interleukin‐6 receptor antibody, tocilizumab

Abstract

Reactive arthritis is a disease with the clinical triad of arthritis, urethritis, and conjunctivitis (1). The onset of the disease is often preceded by bacterial infections of Campylobacter, Chlamydia, Salmonella, Shigella, or Yersinia, either in the urogenital or gastrointestinal tract (2,3). HLA–B27 is strongly associated with reactive arthritis, so that this disease is considered as one of the HLA–B27positive spondylarthropathies. Although the pathogenesis of reactive arthritis remains imperfectly understood, bacterial infections trigger systemic immunoreactions, and overproduction of proinflammatory cytokines has been shown to contribute to sterile joint inflammation (1–4). Several kinds of drugs are used for the management of reactive arthritis, including nonsteroidal antiinflammatory drugs (NSAIDs); disease-modifying antirheumatic drugs (DMARDs) such as sulfasalazine, methotrexate, and leflunomide; corticosteroids; and immunosuppressive drugs, including azathioprine and cyclosporine, whereas the use of antibiotics remains controversial (1–4). Infliximab, a chimeric anti–tumor necrosis factor (anti-TNF ) antibody, and etanercept, a 75-kd TNF receptor fusion protein, reportedly ameliorated symptoms in patients with reactive arthritis (5–8), as well as other HLA–B27-positive spondylarthropathies (9). However, to our knowledge, there have been no reports regarding the efficacy of the humanized anti–interleukin-6 (IL-6) receptor antibody, tocilizumab (10), for reactive arthritis. Here we report a case of reactive arthritis treated successfully with tocilizumab.