In our previous study in AAV, serum levels of Ang-2 were much higher in 15 patients with untreated, severe AAV with glomerulonephritis (GN; 9 with GPA, 6 with MPA) than in three other groups: i) 20 patients with a history of AAV and GN but in remission and on minimal immune-suppressive medication at times of measurement; ii) 10 patients with active GPA limited to granulomatous disease of the respiratory tract but no evidence of systemic necrotizing vasculitis, off immune-suppressive drugs, and iii) 20 healthy age-matched controls [26]. Here, ANGPT2 is linked to anti-neutrophil cytoplasmic antibody-associated vasculitis.