Few diseases in clinical medicine cause as much diagnostic consternation as central nervous system (CNS) vasculitis because of its varying modes of presentation and frequently overlapping clinical and pathological features. There are no pathognomonic clinical or laboratory findings. The purpose of the present retrospective study was to validate the use of the light subunit of neurofilament triplet protein (NFL) and glial fibrillary acidic protein (GFAP) as markers of CNS tissue damage for patients with systemic or isolated CNS vasculitis. Levels of cerebrospinal fluid (CSF) NFL and GFAP were measured using ELISAs. Both CSF NFL and CSF GFAP concentrations were significantly higher in a patient group diagnosed with CNS vasculitis (P < 0.01 and P < 0.05, respectively) than in a patient group for whom CNS vasculitis was excluded. In the future, analysis of CSF NFL in particular, but also GFAP, may be a useful complement in the difficult clinical task of diagnosing CNS vasculitis. © 2002 Wiley‐Liss, Inc.