Central nervous system vasculitis.

Central nervous system vasculitis occurs in a variety of clinical settings. Some exhibit a distinct age preference; others a tissue tropism. Most frequently encountered are giant cell arteritis (temporal arteritis) and vasculitis secondary to infections. The central nervous system may be involved in the antineutrophil cytoplasmic antibody-associated systemic vasculitides and occasionally neurologic abnormalities appear as a presenting manifestation of disease. Isolated angiitis of the central nervous system, a rare form of vasculitis that is restricted to the central nervous system, must be distinguished from other causes of central nervous system inflammation and from noninflammatory vascular disease. We are learning a great deal about the cellular mechanisms of vascular inflammation in general. Some manifestations of the clinical disease result from histologic features of the infiltrate and the size of affected vessel. However, the local consequences of inflammation, such as increased coagulation and altered vasomotor tone, as well as the systemic consequences, such as activation of the central noradrenergic systems, trigeminovascular system, and hypothalamic pituitary adrenal axis, contribute both to pathogenesis of disease and to recovery.