Immune mechanisms in the primary and secondary vasculitides.

Vasculitis, or angiitis, affects both the central and peripheral nervous systems and is increasingly recognized as a cause of neurologic dysfunction. The vascular inflammation may be systemic or organ restricted. Recent work has expanded our knowledge on the pathogeneses of vasculitis. Historically, immune complex mediated vasculitis is best defined but studies now delineate cell mediated immune mechanisms including T cell and endothelial cell interactions. Additional factors in the genesis of vascular inflammatory diseases are also being explored. There are numerous underlying etiologies ranging from primary immunologic disturbances to infections, malignancies, and toxins. In order to plan rational therapies, clinicians need to be aware of current work on the pathogeneses of vascular inflammation as well as exploring specific etiologies in their individual patients.