This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
True about Henoch Schonlein purpura is - 
Select and explain. 
A. Medium vessels vasculitis, B. Renal symptoms sta late in the disaese, C. IgA deposition in mesangium, D. Low Platelet count
C: IgA deposition in mesangium
Answer: C: IgA deposition in mesangium 
Explanation: Answer- C. IgA deposition in mesangiumHenoch - Schonlein purpura is vasculitis of small vessels (capillaries, venule or aerioles) and characterized by deposition of IgA in the wall of involved vessels.H.S. purpgra is characterized by tetrad of purpura ahritis glomerulonephritis, and abdominal pain.Diagnosis is confirmed by presence of palpable purpura with normal platelet count along with one or more of the following:abdominal pain, ahralgia/ahritis and mesangial deposition of IgA.