In our previous study, we have found increased serum levels of HMGB1 in patients with Henoch– Schonlein purpura (HSP), allergic vasculitis (AV), and urticarial vasculitis (UV) and altered HMGB1 distribution in lesional skin in patients with HSP. This evidence concerns the gene HMGB1 and Henoch-Schoenlein purpura.