- IgA vasculitis (IgA, formerly Henoch-Schönlein purpura), without active and/or progressing renal involvement (stable glomerular filtration rate (GFR) >60 ml/min; absence of, or mild-and-stable microscopic hematuria without red blood cell casts; absence of, or mild-and-stable proteinuria (<1g/24 hours); not requiring systemic immunosuppressive therapy).