Clinical analysis of nervous system involvement in ANCA-associated systemic vasculitides.

Objective: To assess the clinical features of nervous system (NS) involvement in patients with ANCA-associated vasculitides (AAV), including microscopic polyangiitis (MPA), Wegener's granulomatosis (WG), and Churg-Strauss syndrome (CSS).
Methods: One hundred and seventy-nine patients admitted to Peking Union Medical College Hospital from 1995 to 2008, including 93 cases of MPA, 61 cases of WG, and 25 cases of CSS, were enrolled in this study. Medical charts including demographic data, clinical features, laboratory findings, treatments and outcomes were systematically reviewed.
Results: NS involvements were observed in 36.6% of MPA, 50.8% of WG, and 76.0% of CSS patients. Peripheral neuropathy predominated in each type of AAV. In CSS and MPA, the majority was mononeuritis multiplex and distal symmetrical polyneuropathy, whereas, differently, 64.5% of WG patients with NS involvement had cranial neuropathy. Central nervous system (CNS) involvement accounted for 21.1%, 29.4%, and 32.3% of neuropathy respectively in CSS, MPA and WG patients, including arachnoid hemorrhage, cerebrovascular neuro-pathy, meningitis, and diffuse brain damage. 157 (87.7%) AAV patients responded to treatment with high dose of prednisone plus immunosuppressants. Thirteen (14.0%) MPA and four (6.6%) WG patients died. The leading causes of death were diffuse alveolar hemorrhage (DAH) (6, 35.3%) and infection (6, 35.3%). No patient died directly of neuropathy.
Conclusion: NS involvement was common in AAVs and the characteristic of NS involvement was different among MPA, WG and CSS patients. DAH and infection instead of NS damage remained the leading causes of death in AAVs.