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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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Periodic Acid Schiff (PAS) stain positive intra-alveolar material is seen in?
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The correct answer is  PAS material in alveoli is accumulated surfactant due to decreased turnover in pulmonary alveolar proteinosis. Characterized by dysfunction of alveolar macrophages which results in decreased surfactant clearance The same material may be coughed up by patients and described as chunky gelatinous plugs. Lipoid pneumonia will show fat globules in macrophages.