[Physiopathology of viral vasculitis]

Viral infections can cause vasculitides via mechanisms that remain incompletely understood but may involve circulating immune complexes or endothelial cell infection. Many viruses are capable of infecting the endothelial cells and modifying their phenotype, thus facilitating thrombosis and inflammatory cell recruitment. Although the main animal models of vasculitis are virus-induced, viruses are responsible for only a minority of cases of vasculitis in humans. However, a role of undetected viruses in vasculitides currently classified as primary cannot be completely ruled out.