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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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What are these crystals that were aspirated from the bursa of an elbow of a patient with rheumatoid arthritis?
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The correct answer is  Answer A. CholesterolThe rectangular, platelike crystals with strong birefringence (both positive and negative) and notched corners are characteristic of cholesterol crystals. Cholesterol crystals are occasionally seen in the bursal fluid of patients who have rheumatoid arthritis.