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What is Characteristic of HSP is - and explain in detail?
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