CXCL13 and spirochaetales infections: These results clearly indicate that highly elevated CSF CXCL13 levels are associated with LNB, or with other spirochetal infections of the CNS.It is obvious from the receiver operating characteristic (ROC) curve analysis (LNB pretreatment samples against all comparison groups) shown in Figure 3 and also from the data presented in Figure 2 that the diagnostic performance of CSF CXCL13 determination with a cut-off 415 pg/ml results in nearly perfect discrimination between the LNB patients and other groups in this sample material.