RT Book, Section A1 Hellmann, David B. A1 Imboden Jr., John B. A2 Papadakis, Maxine A. A2 McPhee, Stephen J. A2 Rabow, Michael W. SR Print(0) ID 1166169544 T1 Henoch-Schönlein Purpura T2 Current Medical Diagnosis and Treatment 2020 YR 2020 FD 2020 PB McGraw-Hill Education PP New York, NY SN 9781260455281 LK accessmedicine.mhmedical.com/content.aspx?aid=1166169544 RD 2022/05/22 AB Henoch-Schönlein purpura, the most common systemic vasculitis in children, occurs in adults as well. Typical features are palpable purpura, arthritis, and hematuria. Abdominal pain occurs less frequently in adults than in children. Pathologic features include leukocytoclastic vasculitis with IgA deposition. The cause is not known.