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Discussion Starter · #1 ·
A 46-year-old Caucasian male is being worked up for abdominal discomfort, loose stool and recent weight less. Intestinal biopsy is performed and periodic acid-Schiff (PAS) reaction is used on the sample (see the slide below). The intense pink discoloration demonstrated on the slide most likely indicates the presence of



A. Peroxidase
B. Calcium
C. Iron
D. Neutral lipid
E. Glycoprotein
F. Alkaline phosphatase
 

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E. Glycoprotein

I love histology! - everything's so pretty...
Peroxidase assays show up brown usually
Alk Phos you could stain a lot of different ways
Iron shows up black usually
Lipids could also look different, congo red or OsO4 black in frozen sections, or absent in paraffin sections
Calcium I'm not sure about
Periodic Acid Schiff shows sugars as pink, so I'd go with glycoprotein.
 

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Discussion Starter · #5 ·
Mondoshawan! you've given excellent details about the picture plus details about other ans choices. very nice, thank you.

The above case is the typical presentation of whipple's disease. The glycoprotein in the cell walls of the actinomycete Tropheryma whippelii colors magenta with PAS and is diastase resistant, making this stain an excellent choice in evaluating tissue for Whipple disease.
 
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