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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
A 22-year-old man with inflammatory bowel disease is noted to have a "string sign" in the ileal area on barium enema. In which of the following conditions is this sign most often seen? (See Fig. below.)
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The correct answer is  The string sign represents long areas of circumferential inflammation and fibrosis. It is seen in the stenotic and non-stenotic phase of Crohn's disease. In addition to the string sign, abnormal puddling of barium and fistulous tracts are other helpful x-ray signs of ileitis. Other radiologic findings in Crohn's disease include skip lesions, rectal sparing, small ulcerations, and fistulas.