The value of LAMP-2-ANCA seropositivity as a biomarker may be greatest among AAV patients who have MPO/PR3-ANCA-negative SVV, but more so in individuals with middle vessel vasculitis (MVV), namely, polyarteritis nodosa (PAN) and large vessel vasculitis (LVV), namely Takayasu’s arteritis (TAK). This evidence concerns the gene MPO and anti-neutrophil cytoplasmic antibody-associated vasculitis.