BACKGROUND: Secondary vasculitis represents a rare extraintestinal manifestation of Crohn's disease (CD). Appropriate and prompt diagnosis is often delayed by uncertainties about the relationship of the vasculitic manifestations and CD. OBJECTIVE: To describe our experience with vasculitis in CD and review the literature with respect to different manifestations and pathophysiological aspects of extraintestinal vasculitic manifestations of CD. METHODS: We report 2 new cases of CD with secondary small-vessel vasculitis. We also extensively review the literature (1960-2007) using a broad range of key words related to secondary vasculitis in CD. Relevant publications were evaluated for the number of reported patients and manifestations of vasculitis. RESULTS: Vasculitis is a rare extraintestinal manifestation of CD. Different types of vasculitis affect large-, medium-, and small-sized vessels associated with CD. Common immunologic features include intestinal inflammation as well as an infiltration of gammadelta-T-cells and/or Th1-type cells into vessel walls. The 2 new cases of secondary vasculitis in CD reported here reflect 2 major types of CD-related inflammatory vascular disorders. The first involves the central nervous system, while the second represents circumscribed Musculus gastrocnemius involvement (so-called "gastrocnemius myalgia syndrome"). Successful treatment of refractory secondary vasculitis in CD with an anti-tumor necrosis factor-alpha antibody is shown for the first time. CONCLUSION: Vasculitis secondary to CD is an uncommon finding. Therefore, it has to be carefully differentiated from other forms of primary or secondary vasculitis with intestinal involvement. Treatment with an anti- tumor necrosis factor-alpha antibody may prove a treatment option in vasculitis as an extraintestinal manifestation of CD.
