[Leg ulcers in systemic diseases].

The collagen vascular diseases and vasculitis, in particular, are occasionally associated with chronic, relapsing lower extremity ulcerations. Different mechanisms can induce such ulcerations, and an understanding of the type of ulcerations is important in the differential diagnosis of patients with leg ulcerations in general, and management of these patients in particular. In this review, the authors analyze the various mechanisms of the leg ulcerations in these patients and their treatments: vasculitis, thrombosis, traumatisms, calcinosis, panniculitis, pyoderma gangrenosum, infections, and induced by treatments.