Nonsystemic Vasculitic Neuropathy: A Clinicopathological Study of 22 Cases

OBJECTIVE: The involvement of the peripheral nervous system in patients with systemic vasculitis has been reported, but nonsystemic peripheral nervous system vasculitis is not so well known. We investigated the clinical, electrophysiological, and pathological features of nonsystemic vasculitic neuropathy (NSVN) in order to establish the clinical and histological manifestations and to promote the earlier diagnosis of the syndrome. METHODS: Biopsies were selected from over 700 sural nerve biopsies performed at the Section of Neuropathology, Neurological Clinic of Athens University Hospital. The diagnosis of vasculitis was based on established clinicopathological criteria. Other causes of peripheral neuropathy were excluded. Complete laboratory, clinical, electrophysiological, and pathological studies were performed in all cases. Results. Nerve biopsies of 22 patients were diagnosed as NSVN. The pathological features were vasculitis and predominant axonal degeneration with a varying pattern of myelinated fiber loss. The vasculitic changes were found mainly in small epineural blood vessels. Mononeuritis multiplex and distal symmetrical sensorimotor neuropathy were equally frequent. Conclusion. NSVN should be suspected in a case of unexplained polyneuropathy without evidence of systemic involvement. Clinical and neurophysiological studies are essential for the detection of nerve involvement, but the specific diagnosis of NSVN may be missed unless a biopsy is performed.