Absence of upper respiratory tract involvement, extracardiac manifestations limited to the skin (mostly purpura) and kidney, along with splenomegaly, hypocomplementemia (low serum C3 and C4), dual ANCA positivity, low ANCA titers, C1q, IgM and other immune reactants in the glomerular immune complex deposits, presence of other autoantibodies like anti-nuclear antibody, rheumatoid factor are all important distinguishing clues and are encountered much more commonly in IE-associated GN than in AAV. This evidence concerns the gene C3 and ganglioneuroma.