Comparable evaluation of serological diagnostic tests (ELISA, IFA and PA methods) for the detection of anti-Borrelia burgdorferi antibody]

We have evaluated the usefulness of the enzyme-linked immunosorbent assay (ELISA), indirect fluorescent antibody assay (IFA) and particle agglutination (PA) method as serological screening tests for Lyme-borreliosis. Serum samples obtained from two patients with Lyme-borreliosis showed marked high antibody titers for Borrelia burgdorferi when measured by these methods. Of the serum of 368 healthy members of the Self-Defense Force in north-eastern Japan screened for the antibody to B. burgdorferi, 8.4%, 3.7%, 4.6% were found positive by the ELISA, IFA, and PA method, respectively. However, Western blot analysis of these "positive" sera demonstrated no identical bands to those seen in the serum from the patients with Lyme-borreliosis. While 85% and 15% of Treponema pallidum hemagglutination test (TPHA)-positive sera (20 samples) showed a false-positive reaction by the ELISA and IFA method, respectively, no cross-reaction to the anti-B. burgdorferi antibody was observed in these sera by the PA method. The analysis of the serum of the patients with autoimmune diseases (rheumatoid arthritis; 11 cases, systemic lupus erythematosus; 46 cases) by the ELISA and PA methods resulted in a cross-reaction to some extent, which suggested that the antibodies produced by autoimmune mechanisms such as the anticardiolipin antibody can cause a cross-reaction to the anti-B. burgdorferi antibody. These findings indicate that the PA and ELISA rather than the IFA method should be recommended for rapid and conventional screening of Lyme-borreliosis and that serum "positive" for the anti-B. burgdorferi antibody determined by these tests should be confirmed by Western blot analysis to negate the cross-reactions.