Hypocomplementemia

Urticarial vasculitis (Urticarial vasculitis) was first reported by MCDuffie in 1973. It is characterized by a rash of wind rashes, with a long duration, accompanied by hypocomplementemia. Inflammatory mediators damage the vascular endothelial cells, resulting in changes in vasculitis, showing the manifestation of leukocyte fragmenting vasculitis. Its etiology is unknown, and hypersensitivity vasculitis caused by iodine allergy, repeated cold irritation, and allergens such as viruses, bacteria, and parasites have been reported.