Elevated CSF CXCL13 levels have also been found in patients with HIV, Cryptococcus neoformans meningitis, congenital toxoplasmosis (21, 28), viral encephalitis (32), viral meningitis (e.g., varicella zoster virus, herpes simplex virus, and tick-borne encephalitis virus [25, 28, 54]), multiple sclerosis (19, 28, 33), and CNS lymphoma (26, 34). Here, CXCL13 is linked to primary central nervous system lymphoma.