Central nervous system vasculitis.

OPINION STATEMENT: A patient presenting with suspected primary central nervous system (CNS) vasculitis is often difficult to manage. Once the diagnosis is suspected, the clinical course may already be severe and warrant timely aggressive treatment with potentially toxic drugs. Definitive diagnosis is often delayed, requiring specialized tests that are only possible in certain centers and sometimes prove to be inconclusive. The need to make a confident diagnosis before starting powerful and potentially toxic immunosuppression, often conflicts with the desire to initiate timely treatment aimed at preventing irreversible neurological dysfunction. The heterogeneity and rarity of this condition is a major obstacle to conducting properly designed, double blinded, placebo-controlled studies. There is no Class I evidence for any form of treatment in these situations, and management guidelines represent expert opinion, based primarily on trials investigating therapies affecting systemic conditions with a CNS vasculitic component. Cyclophosphamide is still the main immunosuppressive drug used during active disease in combination with high dose steroids. Rituximab may be an equally efficacious, less toxic alternative, but its use is still limited due to its cost.