The neuropathies of vasculitis.

Vasculitic neuropathy can occur as an isolated entity (nonsystemic vasculitic neuropathy) but more commonly evolves in the setting of primary systemic vasculitides or secondary vasculitides related to infections, drugs, or connective tissue disorders. Vasculitic neuropathies are usually but not always painful and tend to produce sensory motor or sensory symptoms. Patients with purely motor or small-fiber dysfunction are unlikely to have vasculitis. Deficits are typically multifocal or asymmetric, but distal symmetric polyneuropathy occurs uncommonly. Evaluation requires laboratory tests, electrodiagnostic studies, and nerve or nerve/muscle biopsy. This article reviews classification, clinical presentation, diagnostic evaluation, and management of peripheral nerve vasculitis.