Central Nervous System Vasculitis

Vasculitis is a group of disorders characterized by the inflammation of blood vessels resulting in occlusion and ischemia. The central nervous system (CNS) is a common target for vasculitis. CNS vasculitis can be classified according to the size of the vessels affected (small-, medium-, and large-vessel vasculitis), as well as the underlying etiology including primary vasculitis and vasculitis secondary to either systemic diseases, infections, neoplasms, or drugs. The clinical presentation is heterogeneous, the course may vary from insidious to fulminant, and the manifestations include headache, seizures, encephalopathy, and focal neurological deficits. Diagnosis of CNS vasculitis is challenging. A presumptive diagnosis is usually achieved by the combination of signs and symptoms, neuroimaging features, and serological or cerebrospinal fluid markers, whereas a definitive diagnosis usually requires tissue biopsy. Primary angiitis of the CNS is particularly difficult to diagnose due to the absence of pathognomonic findings. In this chapter, we review common causes of CNS vasculitis and provide an overview of their clinical presentation, diagnostic approach and therapeutic considerations.