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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
In a 27 yr old male most common cause of a colo-vesical fistula would be:
assistant
The correct answer is  Diveicular disease is the most common cause of colovesical fistula, followed by colon cancer and Crohn disease. Diveicular disease and colon cancer are rare in people younger than 40 years. Here this patient is young; hence the most suitable answer is Crohn's disease. Ref: ACP Medicine: Volume 1, 2007, Page 816.