The clinical spectrum of the neurological involvement in vasculitides.

Both the central nervous system (CNS) and the peripheral nervous system (PNS) are major target organs in primary vasculitides. They may either be affected in the setting of systemic vasculitis, potentially involving any other organ, or they may be the sole site of the inflammatory process. In both cases, the clinical pattern of PNS involvement is essentially uniform, presenting as sensory axonal polyneuropathy or mononeuritis multiplex. The damage is related to the ischemic occlusion of the vasanervorum due to small-vessel vasculitis. On the contrary, the range of manifestations of CNS vasculitis is much wider and several pathogenetic mechanisms are implicated, including angiitis of the hemispheres and spinal cord, thrombosis of dural sinuses, stenosis and aneurysms of medium and large arteries, granulomatous meningeal involvement and direct cytokine damage presenting with encephalopathy. Besides, even extracranial noninflammatory vascular disease may induce CNS symptoms, as is the case of carotid stenosis, vena cava syndrome and renovascular hypertension. In this paper we will review the broad spectrum of clinical manifestations of CNS and PNS neuropathy as they occur in primary systemic and non systemic vasculitides.