Inflammation of the vessel wall.
- Infectious
- Non-infectious
Infectious
- Most commonly, fungi -- Aspergillus
- Usually due to systemic infections in immune compromised
Non-infectious
Caused due to autoimmune reactions.
Many specific types are known and they are classified based on their characteristic features, mainly the types of vessels they affect, but in general -- they overlap in their presentation.
Mechanisms
To this day, most vasculitides have an unknown etiology; however, there have been three suggested mechanisms:
- Immune complex deposition
- Neutrophil-mediated
- Anti-endothelial activity
Immune complex deposition
Some vasculitides are caused due to the presence of immune complexes within vessel walls.
- Types:
- Drug hypersensitivity
- In some cases, drugs such as penicillin bind to proteins and act as antigens to which antibodies can bind
- Secondary to
- Drug hypersensitivity