Vasculitides in the context of HIV infection.

Vasculitides are a rare but major manifestation of HIV infection, with an incidence of less than 1%, excluding adverse drug reactions. A wide spectrum of vasculitides have been found in association with HIV infection, reflecting almost every pattern and type of vasculitis of small, medium and large vessels. Vasculitis in HIV-infected patients can arise as a result of infection with a known pathogen or in response to a triggering factor, but may also arise in the absence of any identifiable cause. Although the vasculitides seen in HIV infection are varied, one feature--namely inflammation of the vessel wall--is common to all. Various pathogenic mechanisms have been implicated in the induction of vasculitis, including cell-mediated inflammation, immune complex-mediated inflammation and autoantibody-mediated inflammation. This review will focus on some of those vasculitides that have been described in HIV-infected patients, and will discuss the association of atherosclerosis with vasculitides.