The antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitides are a group of small-vessel vasculitides that results in inflammation of the small blood vessels.
It has a diverse range of clinical manifestations that commonly involve not only the upper airways, lungs, and kidneys but also the eyes, skin, joints, nerves, and, potentially, many other sites. This diversity is why ANCA-associated vasculitides can have such a wide scope of clinical presentations and disease severity.
Entities in this group of diseases include granulomatosis with polyangiitis (formerly known as Wegener's granulomatosis), microscopic polyangiitis, and eosinophilic granulomatosis with polyangiitis (formerly known as Churg–Strauss syndrome).
Skin involvement is a common clinical feature in all three forms of ANCA-associated vasculitis, with various manifestations.