VASCULITIDES ASSOCIATED WITH INFECTIONS, IMMUNIZATION, AND ANTIMICROBIAL DRUGS

Many pathogenic microbes can induce a complex series of immunologic, e ndothelial-cell, and hemorheological activation cascades and dysfuncti ons and can cause interactions of various components of the vessel wal l with formed and noncellular elements of the blood. These interaction s can result in manifold vasculitides. This article reviews the pathog enetic, clinicopathologic, and therapeutic aspects of infection-relate d vasculitides; it includes a brief discussion of parasitic, drug-rela ted, and immunization-associated vasculitides as well as of the infect ion-related features of vasculitides of the central nervous system, re tinal vasculitides, ecthyma gangrenosum, and erythema nodosum. Viruses are mainly associated with small-vessel vasculitides, whereas bacteri al infections affect vessels of all sizes, including the aorta. The va sculitides associated with fungal infection usually are characterized by erythema nodosum and involve large vessels. The search for microbes as causes of or contributors to vasculitides should continue. Infecti ous vasculitides may become increasingly important as the number of im munocompromised patients grows.