Objective: To analyze the main characteristics of patients infected with hepatitis C virus (HCV) presenting with different types of vasculitis syndrome.
Methods: We retrospectively compared 2 groups of patients with HCV presenting with systemic vasculitis: 10 with biopsy proven polyarteritis nodosa-type systemic vasculitis (PAN, Group 1) and 7 with mixed cryoglobulinemia syndrome (MC, Group 2).
Results: Patients of Group 1 presented with different features than Group 2: life threatening systemic vasculitis (10 vs 0; p < 0.01), severe multifocal sensorimotor mononeuropathies versus distal moderate sensory polyneuropathies, malignant hypertension (5 vs 0; p = 0.04), cerebral angiitis (2 vs 0), ischemic abdominal pain (2 vs 0), kidney and liver microaneurisms (2 vs 0), increased erythrocyte sedimentation rate and C-reactive protein (7 vs 0; p < 0.01), renal insufficiency (5 vs 0; p = 0.04), HCV genotype 1b (3 vs 6; p = 0.06), and lower activity of chronic hepatitis (p = 0.02). Neuromuscular biopsies showed lesions of vasculitis in all patients, but the type of vasculitis was different in Group 1 compared to Group 2: medium size artery involvement (7 vs 0; p < 0.01), necrotizing vasculitis (10 vs 0; p < 0.01), and mononuclear cell infiltrate in perivascular areas (0 vs 7; p < 0.01). Using prednisone, plasma exchanges, and interferon-alpha, complete recovery was obtained in all PAN-type patients except one. In Group 2 patients, interferon-alpha did not have any effect on the peripheral neuropathy.
Conclusion: HCV infection may be associated with different types of systemic vasculitis, i.e., polyarteritis nodosa or mixed cryoglobulinemia. Because of differences in clinical and pathological features and therapeutic strategy, PAN-type vasculitis should be distinguished from MC-type vasculitis in HCV patients.