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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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Which of the following infection gives a positive Casoni test?
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The correct answer is  Casoni's test is based on the principle of immediate hypersensitivity. The antigen used is hydatid fluid collected from animal or human cysts and is sterilised by Seitz or membrane filtration. 0.2 ml of the antigen injected intradermally. In positive cases a large wheal about 5 cm in diameter, with multiple pseudopodia like projections appears in 25-30 minutes. This is a sensitive test but not specific. Ref: Medical Parasitology By Bhatia, 3rd edition, Page 221.