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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.
user
An 85-year-old hypertensive man is evaluated in the emergency department for recent onset epistaxis. His blood pressure is 150/80 mm Hg, and hematocrit is 39%. What is the most likely source of bleeding?
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The correct answer is  Epistaxis in children and young adults usually arises from the anterior nasal septum (Kiessel bach's plexus). In elderly persons, however, spontaneous rupture of a sclerotic blood vessel in the posterior nasal septum is usually the cause of bleeding, especially in combination with hypertension.