Seroreactivity to Borrelia burgdorferi antigens in early rheumatoid arthritis: a case-control study.

This study investigates the seroreactivity to Borrelia burgdorferi antigens of patients suffering from rheumatoid arthritis (RA) for < 5 yr. Subjects were matched with controls for age, sex and area of residence in order to minimize the risk of differential exposure to B. burgdorferi. A total of 57 pairs were tested by immunofluorescence assay (IFA) and Western blotting. Only two RA patients showed positive IFA results, and another was positive by Western blot analysis. No significant difference in Lyme seropositivity was detected between cases and controls using either serological test. Furthermore, no significant difference in antibody response was observed to specific or non-specific proteins (e.g. Osp C, 93 kDa protein, flagellin, heat shock proteins). These results do not support the previous suggestions that B. burgdorferi may be involved in the aetiology of RA, or that RA favours the production of antibodies that cross-react with B. burgdorferi proteins.