[Virus-associated arthritis].

Epidemiological studies suggest a viral etiology in approximately 1% of patients presenting with acute arthritis. The arthritogenic effect of viral infections may be related to viral invasion of synovial cells, the cellular and humoral immune response to viral antigens or by induction of autoimmunity. Viral arthritis can mimic rheumatoid arthritis by presenting as a symmetrical polyarticular disease often accompanied by a rash and influenza-like symptoms. Serological testing for pathogen-specific IgM and IgG antibodies is frequently performed for establishing a viral etiology of arthritis. Virus isolation from the joints or detection of viral nucleic acids in the synovium or synovial fluid is only rarely successful and does not always provide proof of a viral origin of arthritis. While viral arthritis in most cases is self-limiting, protracted disease can occur.