Detection of intrathecally produced specific
antibodies (AI) is essential in the diagnosis of
Lyme neuroborreliosis (LNB); however, the performance of various newer AI detection methods has not been systematically assessed. Here we assessed and compared advanced test systems for detecting borrelia
IgG-AI and
IgM-AI. Serum and cerebrospinal fluid (CSF) samples from well-defined LNB and
tick-borne encephalitis (TBE) patients, 25 each, were tested with three antibody detection systems, one based on chemiluminescence (CLA) and two based on
enzyme-linked
immunosorbent assays (ELISA), employing different
antigens for detection of
IgG and
IgM antibodies. In samples from patients with LNB,
IgG-AI was detected in 20 samples by CLA, 19 by ELISA1, and 22 by ELISA2, and
IgM-AI was detected in 16 samples by CLA, six by ELISA1, and 11 by ELISA2. In samples from TBE patients,
IgG-AI was positive in one case by CLA and ELISA2, and in 7 cases by ELISA1, whereas
IgM-AI was positive in one case by CLA and in none by ELISA.
IgG-AI and
IgM-AI were not detected within the first week of disease. Duration of disease correlated with
IgG-AI while
IgM-AI results were heterogeneous for each test assay. Moreover, the levels of
IgG-AI, but not
IgM-AI, correlated with
protein concentration in CSF.
IgG is the relevant
immunoglobulin isotype for detecting intrathecal synthesis of borrelia
antibodies. The highest sensitivity and specificity were achieved by the antibody detection assay using VlsE IR6
peptide. Detection of
IgM-AI yielded heterogenous results and did not support the laboratory diagnosis of LNB.