All of the following features may be used to distinguish PAN from microscopic Polyangitis, Except:: (A) ANCA positivity, (B) RBC cast in urine, (C) Necritizing vasculitis, (D) HBV infection
Answer is C. Answer is C (Necrotizing vasulitis): Both polyaeritis nodosa and microscopic polyangitis are characterized by histologicaly by necrotizing vasculitis. Clinical Features PAN MPA Kidney Involvement * Renal vasculitis with infarcts and microaneurysms Yes No * Rapidly progressive glomerulonephritis with crescents No Yes Lung involvement * Alveolar hemorrhage No Yes Laboratory data Yes (10%) No * HBV-infection * ANCA Negative Positive (p-ANCA) Abnormal angiogram with microaneurysms Yes No * Histology Necrotizing vasculitis Necrotizing vasculitis (no granulomas) * Relapses Rare Common