IN THIS issue of the ARCHIVES, de Groot et al1 report the neurological features of 128 consecutive patients with Wegener granulomatosis (WG) seen at their institution between January 1, 1991, and June 30, 1997. Clinical features suggesting this diagnosis include hematuria or red cell casts, abnormal chest radiography (ie, nodules, cavities, or fixed infiltrates), hemoptysis, and nasal discharge or oral ulcers. Pathologic features of WG are granulomatous inflammation of the respiratory system and other tissues, and necrotizing vasculitis affecting small and medium-sized vessels.2- 4 While central nervous system involvement was infrequent in the case series by de Groot et al, almost half of the patients had peripheral neuropathy. Mononeuritis multiplex and symmetric distal polyneuritis occurred with approximately equal frequencies. In some patients, onset of peripheral nervous system deficits was acute or subacute, in others gradual. Electrophysiologic studies demonstrated axonal involvement in almost all of the patients with WG, with a few patients also showing evidences of segmental demyelination.