Emergence and treatment of chikungunya arthritis.

Purpose of Review: To review the emergence, clinical features, pathogenesis, and treatment of acute chikungunya (CHIK) fever and chronic CHIK arthritis.
Recent Findings: Since 2004, CHIK, an arboviral infection, has spread throughout the world, infecting millions of people. The illness occurs in two phases: an acute viremic infection followed by chronic arthritis. In less developed countries, there are limited resources and effective treatment. For acutely ill CHIK fever patients, management is symptomatic. The treatment of chronic CHIK arthritis should be determined by an understanding of pathogenesis. Is chronic CHIK arthritis a persistent viral infection or a postinfectious inflammatory process? Multiple proinflammatory cytokines, chemokines, and growth factors have been identified in chronic CHIK arthritis. Attempts to isolate CHIK virus from synovial fluid have been unsuccessful. Given pathogenetic similarities (as well as differences) compared with rheumatoid arthritis and the painful, disabling nature of the arthritis, it is not surprising that disease-modifying antirheumatic drugs such as methotrexate have begun to be used.
Summary: CHIK infection has emerged with major arthritic epidemics for which evidence-based therapy is limited. But there is an opportunity to improve the treatment of chronic CHIK arthritis and, from this disease, to gain understanding of the pathogenesis and treatment of inflammatory arthritis more generally.