Background: Prompt differentiation of nonsystemic vasculitic neuropathy (NSVN) from systemic vasculitic neuropathy (SVN) without antineutrophil cytoplasmic antibodies or organ involvement (SVN-) is challenging but crucial given the differences in management. Our primary objective was to identify predictors of SVN- versus NSVN.
Methods: We retrospectively identified patients seen at either of two centers for histologically definite or probable vasculitic neuropathy diagnosed as SVN- or NSVN. Clinical, electromyographic, laboratory, and histological data at diagnosis and last follow-up were collected.
Results: We included 98 patients, of whom 46 (47%) had NSVN and 52 (53%) SVN-. Symptoms and neurophysiological findings did not significantly differ between the two groups. By univariate analysis, compared to the NSVN group, the SVN- group had more patients with C-reactive protein ≥ 10 mg/L (44.2% vs. 17.4%, p < 0.01), antinuclear antibodies (42.3% vs. 21.7%, p = 0.04), and low C3 or C4 (23.1% vs. 4.3%, p = 0.02). All three associations were confirmed by multivariate analysis. By multivariate analysis adjusted for symptom duration, muscle vasculitis also was associated with SVN- (OR, 8.33; 95% CI, 2.63-25.00; p < 0.01).
Conclusion: Simple, readily available laboratory and histological variables may help to rapidly distinguish SVN from NSVN.
Keywords: diagnosis; peripheral nervous system diseases; vasculitis.
© 2025 The Author(s). European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.