Inflammation of the blood vessels (vasculitis) may be caused when antibodies that have attached to antigens in the blood (immune complexes), are deposited on the blood vessel walls. These purplish spots can be felt in the skin. They do not turn white (blanch) when pressed. As the condition progresses, they may become larger and more bruise-like (ecchymotic), and some may develop central ulceration or necrosis (tissue death).
Reviewed last on: 5/31/2009
Mark James Borigini, Associate Clinical Professor of Medicine, University of California, Irvine, Irvine, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.