PATHOGENESIS OF HEMORRHAGIC VASCULITIS IN CHILDREN (HENOCH SCHÖNLEIN PURPURA) AND CHANGES IN THE HEMOSTASIS SYSTEM

Abstract

The article discusses changes in the hemostasis system in children with hemorrhagic vasculitis, in particular, damage to the walls of small vessels by immune complexes circulating in the circulatory system and activated components of the complement system, and then activation of all parts of the hemostasis system, as well as changes in the hemostasis system of blood vessels, platelets, plasma. Hemorrhagic vasculitis (Henoch–Schönlein purpura or IgA vasculitis) is the most common type of pediatric vasculitis that may affect adults as well. It is classified as a type of small-vessel vasculitis. It can cause cutaneous and systemic symptoms with a minority of patients developing kidney failure. Little is known about the specific pathophysiology of this disorder, except that it is believed to occur in individuals with abnormally glycosylated IgA1. Serum aberrant IgA1 may form large antigen–antibody complexes which, due to a defective clearance, are able to deposit in the small vessels of the skin, kidney, gut, and joints. A variety of factors, including infectious agents, drugs, and vaccines, have been identified as potential triggers. The pediatric form of this pathology is generally considered benign and self-limited. In contrast, IgAV in adults is less common but often associated with worse clinical course and outcome