Neuropathy with Systemic Vasculitis
- Vasculitides are systemic or localized condition in which blood vessel walls are infiltrated and damaged by inflammatory cells; with secondary ischemic injury.
- Most vasculitides are idiopathic and presumably mediated by autoimmune processes.
- Idiopathic vasculitides ensue from cellular (T lymphocytes) and humoral immune (secreted antibody) response to specific antigens that trigger a complex cascade of immune and inflammatory reactions.
- Knowledge of initial antigen triggering process still primitive.
- In general, vasculitides are uncommon diseases.
- Neuropathy common in systemic necrotizing vasculitides.
Neuropathy rare in temporal arteritis, and the predominately cutaneous vasculitides
- Vasculitic neuropathy can occur at any age-most common 6-8th decade. Female/male ratio-4/3.
- Systemic vasculitides affecting small arteries and arterioles commonly produce peripheral neuropathy-“mononeuritis multiplex” or multiple mononeuropathy.
- Pts with vasculitic neuropathy secondary to systemic disease-multiorgan pathology soon follows (skin, renal, rheumatic, pulmonary, GI. Weight loss, fatigue, myalgia, arthralgia occur in both systemic and non systemic vasculitic neuropathy.
- Mild to moderate elevation SED rate occurs in 60% pts. Systemic more abnormal than non-systemic.
- EMG/NCS: Asymmetrical or mutifocal, distal predominant axonal sensorimotor neuropathy. Partial focal conduction block due to axonal degeneration, not demyelination observed; may clear with repeat testing.
- Muscle Biopsy: Inflammatory cell infiltration within the vessel wall and signs of vascular injury such as fibrinoid necrosis.