CXCL13 concentrations in sera from patients with clinically evident and microbiologically confirmed Lyme neuroborreliosis (circles), clinically evident but microbiologically unconfirmed Lyme neuroborreliosis (squares), clinically suspected Lyme neuroborreliosis (triangles), or tick-borne encephalitis (inverted triangles), from blood donors (diamonds), and from patients with other neurological diseases (asterisks). The horizontal lines represent the medians and the interquartile ranges.