Figure 2.

Pathogenic model highlighting the differences between PR3-ANCA and MPO-ANCA vasculitis. PR3-AAV is more common in the northern parts of the world whereas MPO-AAV is more common in the southern parts. Different genetic backgrounds have been found and different etiologic factors are considered. Clinically and histologically both vasculitides differ. On the cellular level, PR3 and MPO exert different effects on endothelial cells. These differences possibly point out separate pathogenic pathways.