Treatment resistant Lyme arthritis caused by Borrelia garinii

Lyme arthritis is caused in Europe by three main pathogenic species of Borr elia burgdorferi sensu late: Borrelia burgdorferi sensu stricto, Borrelia g arinii, and Borrelia afzelii. Because few synovial samples have yet been an alysed by species-specific DNA amplification methods, further studies are n eeded to define the spectra of clinical manifestations associated with thes e different species. Two cases of treatment resistant Lyme arthritis are re ported here, in which DNA amplification of the flagellin gene followed by d ot-blot hybridisation in the synovial fluid identified B garinii as the cau sative agent. Clinical and biological data did not differ from the usual de scriptions of Lyme arthritis, but as the recently reported molecular mimicr y between OspA and hLFA1 is not applicable to B garinii, the pathogenesis o f the present cases remains unclear. Future studies should aim at assessing the role of B garinii in European Lyme arthritis and its possible pathogen ic and therapeutic consequences.