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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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Flask shaped undermined ulcers in rectosigmoid area are seen in
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The correct answer is  Most amoebic ulcers occur in the rectosigmoid. On sigmoidoscopy shallow skip lesions and 'flaskshaped' or 'collar-stud' undermined ulcers may be seen and can be biopsied or scrapings can be taken along with mucus for immediate microscopic examination. The presence of trophozoites distinguishes the condition from ulcerative colitis.Ref: Bailey and Love 27e pg: 58