Disease mechanism

The interaction between the activated alternative complement pathway, neutrophils and C5a is at the heart of vasculitic damage in AAV.

AAV pathogenesis


The development of AAV is a complex and multifactorial autoimmune process1,2

The initial causes of AAV are currently unclear.1,2 Predisposing factors such as microbial infection, genetic influence, environmental agents and specific drugs are all fundamental to the development of AAV.1,2

Exposure to silica, pesticides, fumes, construction materials, hydrocarbon (cleaning agents, paint, diesel), drugs (propylthiouracil, hydralazine, D-penicillamine, cefotaxime, minocycline, anti-TNF agents, phenytoin) and certain psychoactive agents may all cause AAV.1,2

References & footnotes
  • Stage 1
  • Stage 2

ANCA involvement
Loss of immune tolerance to ANCA antigens and development of ANCA by plasma cells1

ANCA are most commonly directed against the neutrophil lysosomal enzymes PR3 and MPO in GPA and MPA, respectively1-5

References & footnotes

The importance of complement and neutrophils in AAV activation


C5a plays a major role in the pathogenesis of AAV, amplifying ANCA-induced inflammation and vascular damage1

References & footnotes

Introduction to AAV

AAV is a rare, severe small vessel vasculitis that affects multiple organs and has a high acute mortality risk

Disease mechanism

The interaction between the activated alternative complement pathway, neutrophils and C5a is at the heart of vasculitic damage in AAV

Current therapies

Treatment has improved but treatment-related complications remain common

Patient experience

AAV is an emotional journey from the patient's perspective

Investigate AAV

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