Vasculitis and peripheral neuropathy.

PURPOSE OF REVIEW: Vasculitis of medium-sized and small vessels commonly affects peripheral nerves and can occur in context of a systemic vasculitis with multiorgan involvement or a nonsystemic vasculitis limited to the peripheral nervous system. This review summarizes the clinical and pathological features of systemic and nonsystemic vasculitis of the peripheral nervous system.

RECENT FINDINGS: Vasculitis of peripheral nerves is a diffuse process that affects the vasa nervorum along the entire length of affected nerves but appears to cause injury primarily in a zone in the proximal-middle of the nerve that is particularly susceptible to ischemic injury. Nerve biopsy can help establish the diagnosis of a systemic vasculitis, particularly when other organ involvement is not clinically apparent, and is required for diagnosis of nonsystemic vasculitic neuropathy. Observational studies suggest that nonsystemic vasculitic neuropathy responds to immunosuppressive therapy but conclusive data are lacking.

SUMMARY: The current review summarizes the clinical and pathological features of both systemic and nonsystemic vasculitis of the peripheral nervous system so that clinicians can better recognize, make a more timely diagnosis, and thus treat this condition more effectively in their patients.