How is general presentation of Henoch-Schönlein Purpura?

• Child between 4 and 7 y.o • Vascular purpura by flare-ups predominant on the extensor surfaces of joints • Abdominal pain • Arthralgia of the large joints of the lower limbs. • Histo: fibrinoid necrosis, leukocyte infiltration, • DIF: IgA, C3 deposits in the vessel walls