Pathology Periodic Acid Schiff (PAS) stain positive intra-alveolar material is seen in A Alpha 1 antitrypsin deficiency B Lipoid pneumonia C Abetalipoproteinemia D Pulmonary Alveolar Proteinosis 💡 Explanation Periodic Acid Schiff (PAS) stain positive intra-alveolar material is seen in ✓ Correct Answer: D. Pulmonary Alveolar Proteinosis