[Lyme arthritis: the joint lesions in Lyme borreliosis in the USA].

Of 55 untreated patients with erythema migrans only 20% were free of follow-up manifestations of Lyme's disease. The rest exhibited episodes of articular, periarticular or musculoskeletal pains (18%), one or more episodes of arthritis (51%) or chronic arthritis (11%). Lyme's arthritis arises due to invasion of Borrelia burgdorferi into articular tissues. This became evident after detection of borrelian DNA in the synovia. The study of different cytokine concentrations in the synovial fluid in 83 patients with Lyme's arthritis showed that chronicity of arthritis depends on IL-1b and IL-1ra balance. As indicated by examination of 80 patients with Lyme's arthritis chronic persistence of articular syndrome in 57% was associated with HLA-DR4, in 43% with HLA-DR2. Lyme's arthritis requires long-term treatment. In its failure arthroscopic synovectomy is indicated.