Primary and secondary vasculitic neuropathy.

Necrotizing vasculitis occurs as a primary phenomenon in connective tissue disorders and cognate fields, including polyarteritis nodosa and the Churg and Strauss syndrome variant, rheumatoid arthritis, systemic lupus and Wegener's granulomatosis. In all these conditions focal and multifocal neuropathy occur as a consequence of destruction of the arterial wall and occlusion of the lumen of small epineurial arteries. Vasculitis may also complicate the course of other conditions ranging from infection with the HIV and with the B and C hepatitis viruses to diabetes and sarcoidosis. Pathologically polymorphonuclear cells are present in the infiltrates of the vessel wall in primary necrotizing vasculitis, while in secondary vasculitis the inflammatory infiltrate is mainly composed of mononuclear cells. In all instances symptomatic vasculitis requires corticosteroid to control the inflammatory process and prevent further ischemic nerve lesions.