Antibodies to Borrelia burgdorferi in European populations.

We compared the antibodies to B. burgdorferi in three different populations in order to evaluate the diagnostic reliability of Lyme borreliosis serologic analysis. The subjects included 25 patients with Lyme borreliosis (Group 1); 50 patients with diseases of unknown cause, B. burgdorferi ELISA-positive in serum and without B. burgdorferi infection (Group 2); and 1,251 individuals without Lyme borreliosis (Group 3). All samples were tested for B. burgdorferi B31 and B. afzelii antigens using ELISA. The positive results of the ELISA B. burgdorferi B31 assay were confirmed with Western blot for the same strain. In Group 3, 162 (12.9%) patients were ELISA positive for B. burgdorferi B31, while only 6 (0.6%) patients had IgG ELISA antibodies to B afzelii. Bands in WB were detected in 104 (8.4%) of the Group 3 subjects. The bands found to be most reliable for the identification of strain B. burgdorferi B31 by IgG WB were those representing the 93, 39, 34, and 23-kDa proteins. Our results show that serologic diagnosis of Lyme borreliosis is far from clearly established. To date, the only reliable criteria are clinical ones correlated with laboratory evidence.