
Overview
These red (erythematous), hive-like (urticarial) spots (plaques) are caused by inflammation of the blood vessels (urticarial vasculitis) and do not change over a 24-hour period. They may or may not turn white (blanch) with pressure.
Review Date 5/2/2021
Updated by: Diane M. Horowitz, MD, Rheumatology and Internal Medicine, Northwell Health, Great Neck, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.