Anti-Borrelia burgdorferi immunoglobulin seroprevalence in pulmonary sarcoidosis: a negative report.

The aetiology of sarcoidosis is still unknown. An infectious microorganism as causal agent for this disease could not be identified, but high titres of antibodies against Borrelia burgdorferi were detected in Chinese studies implying a causality with this disease. These findings, however, could not be reproduced by other researchers. The aim of this study was, therefore, to evaluate the possible role of these spirochetes in the pathogenesis of sarcoidosis by serological examinations. Sixty sera of patients suffering from sarcoidosis were examined for anti-B. burgdorferi immunoglobulin by enzyme-linked immunosorbent assay (ELISA). ELISAs for these antibodies show a high sensitivity, but a low specificity; therefore, a specific immunoblot was used to confirm positive results. Initially, 8% of the patients were reactive in the ELISA, and 20% of these could be confirmed by immunoblot. Therefore, the prevalence for B. burgdorferi antibodies in sarcoidosis patients was 1.6%. This result did not differ significantly from the prevalence of B. burgdorferi antibodies in 1,000 regular blood donors of the city of Hamburg (7% reactive in the ELISA, 38% confirmed via immunoblot, prevalence 2.7%). The hypothesis of causality between a B. burgdorferi infection and sarcoidosis cannot be confirmed by this data.