This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Urinary tract, Subject name: Pathology
[{'content': 'Characteristic of HSP is - \nSelect and explain. \nA. IgA deposition, B. IgG deposition, C. IgE depostion, D. IgD depostion', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Henoch-Schonlein purpura is a systemic hypersensitivity disease of unknown cause characterized by a purpuric rash, colicky abdominal pain (presumably due to focal hemorrhages into the gastrointestinal tract), polyahralgia, and acute glomerulonephritis. All these changes result from the deposition of circulating immune complexes within vessels throughout the body and within the glomerular mesangial regions. Ref: Textbook of pathology Harsh Mohan 6th edition page 674', 'role': 'assistant'}]