Immune complex-mediated cutaneous vasculitis in a scar--the importance of local anatomical factors.

A vasculitic rash developed on the legs and arms of a 47 year old woman. Similar vasculitic lesions also erupted in a scar sustained ten years previously. Circulating immune complexes consisting of IgG were detected by Clq binding. We discuss the factors involved in the localization of vasculitic lesions, and in particular stress the role of microvascular injury.