CNS vasculitis.

Central nervous system vasculitis (CNSV) is a complex disease that poses considerable diagnostic and therapeutic challenges. It is divided into primary angiitis of the CNS (PACNS), or secondary angiitis of the CNS when associated with systemic conditions. Clinical presentation can be extremely variable and there is no classic presentation. In addition, there is no single diagnostic test and the sensitivity/specificity of all currently available tests is suboptimal. As such, an exhaustive approach with thorough historical data, physical examination, and corroborating investigations should be performed to exclude or confirm a diagnosis of CNSV. Infectious, neoplastic, and autoimmune conditions should be carefully evaluated. Knowledge of CNSV mimics is crucial given the therapeutic and prognostic implications. Reversible cerebral vasoconstriction syndrome is now recognized as the most common mimicker of PACNS. Much progress has been made in the understanding of PACNS histopathology, and specific clinical subsets and their response to treatment. Contrary to historical reports, recent PACNS cohorts achieved favorable clinical outcomes when early diagnosis and prompt treatment was initiated. Successful treatment with newer drugs has also been reported in PACNS cases. Newer imaging modalities hold promise for distinguishing inflammatory from noninflammatory vascular lesions. In this review, the authors provide a broad overview with updates on the types of adult CNSV along with its clinical assessment, diagnosis, and treatment.