Cross-reactivity between Borrelia burgdorferi and "arthrogenic" bacteria in sera from patients with reactive arthritis.

The occurrence of specific antibodies for "arthrogenic bacteria" and Borrelia burgdorferi was analysed in sera samples from 30 patients with reactive arthritis. The control group consisted of 30 healthy blood donors. Our data showed that 66.6% (20) of the 30 examined patients had positive tests for Borrelia burgdorferi antigens and of all the patients, most of them (85%) had increased antibody levels against Salmonella antigens, 30% had increased levels of antibodies against Shigella antigens and 10% had antibodies for Yersinia antigens. Our findings indicated that the presence of antibodies to Borrelia burgdorferi and "arthrogenic enteric bacteria" in sera samples of patients with REA is evidence of wide cross-reactivity between these microorganisms.