PAS does not stain:
PAS Stain in used for glycogen and mucopolysaccharide containing structures. There are 2 type of PAS positivity (a) Diastase sensitive PAS+VE It occurs is I Ewing sarcoma II Primitive neuro ectodermal tumors III Glycogen storage disease IV Seminoma V Embryonal rhabdo myosarcoma (b) Diastase Resistant PAS +ve I alpha one antitrypsin Deficiency II alveolar soft pa sarcoma
Fungal cell wall
Basement membrane of bacteria
Glycogen
Lipids