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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Hypersensitivity vasculitis is seen most commonly in -
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The correct answer is  Pathology hypersensitivity vasculitis 

In hypersensitivity vasuculitis, postcapillary venules are the most commonly involved vessels, capillaries and arterioles are involved less frequently.
It is primarily a disease of small vessels.
It is characterized by leukocytoclasis, a term that refers to the nuclear debris remaining from the neutrophils that have infiltrated in and around the vessels during the acute stages.