o Renal involvement manifests as microscopic or even gross hematuria and may occur in 25%or more of patients.The long-term prognosis in children with gross hematuria is very good;however, progressive golmerular disease and renal failure may develop in a small percentage, so that careful follow-up supervision is necessary for those with hematuria.⚫ Renal involvement manifests as microscopic or even gross hematuria and may occur in 25% or more of patients. The long-term prognosis in children with gross hematuria is very good; however, progressive golmerular disease and renal failure may develop in a small percentage, so that careful follow-up supervision is necessary for those with hematuria