Prospective study on the chemokine CXCL13 in neuroborreliosis and other aseptic neuroinfections

• CSF CXCL13 levels were higher in neuroborreliosis than in viral neuroinfections.
• CXCL13 CSF levels correlated more closely with pleocytosis than with antibody index.
• Part of neuroborreliosis patients had positive antibody index and low CXCL13 levels.
• CXCL13 testing could help in early neuroborreliosis with negative antibody index.

The study evaluates the clinical significance of CXCL13 (leukocyte chemoattractant synthesized in CSF ) in Lyme neuroborreliosis (LNB) and other aseptic CNS infections.244 patients with symptoms of neuroinfection and/or LNB were divided into groups: A - patients with LNB-positive antibodies in serum and CSF (96) or CSF only (14); B - patients with aseptic non-borrelial neuroinfections (82); C - negative controls (52). Group A was divided into A1–A4 according to pleocytosis in CSF and AIIgG positivity.The highest CSF CXCL13 concentrations (max. 81,287.60 pg/ml; median 1766.90 pg/ml) were in A1 (positive AI, pleocytosis) and A3 (negative AIIgG, pleocytosis; max. 7201,60 pg/ml, median 56.22 pg/ml). A2 (positive AI without pleocytosis) and A4 (negative AI without pleocytosis) had low CXCL13 levels - A2 max. 650.50 pg/ml (median < 7.80 pg/ml); A4 max. 118.56 pg/ml (median < 7.8 pg/ml). In B the median was 28.10 pg/ml (max. 595.87 pg/ml). In C the CXCL13 concentrations were the lowest (max. 83.83 pg/ml; median < 7.80 pg/ml). The lowest cut-off was 29 pg/ml (sensitivity 90.0%, specificity 72.2%), the highest one 400 pg/ml (sensitivity 59.6%, specificity 94.0%). The group differences of serum CXCL13 were insignificant.The highest concentrations were at the beginning of the disease. In LNB CXCL13 correlates better with the CSF pleocytosis than AI positivity.