Wegener's granulomatosis and ANCA syndromes.

The nervous system is involved in approximately 25% of patients with classical Wegener's granulomatosis. The spectrum of this disease has been broadened with the discovery of the anti-neutrophil cytoplasmic antibodies, which are found in diseases sharing many clinical features. The ANCA testing may indicate a common mode of pathogenesis. The definitive diagnostic marker is histological, and that forms the best guide to specific therapy.