Periodic Acid-Schiff Stain
Use
Periodic Acid-Schiff (PAS) stain is utilized for detecting polysaccharides, like glycogen, and mucosubstances, such as glycoproteins, glycolipids, and mucins in tissue samples. It aids in identifying pathological conditions including glycogen storage diseases, adenocarcinomas, and fungal infections. PAS staining is also useful in diagnosing alpha-1 antitrypsin deficiency and in highlighting Pautrier microabscesses typical in mycosis fungoides and Sézary syndrome.
Special Instructions
Fresh Tissue: Specimens may be fixed in formalin for 6-72 hours by collection sites, then transferred to 70% ethanol for storage at 2-8°C if needed long-term. This is not preferred. Samples should be tested within 3 months after being placed in ethanol. Unstained slides require positively charged glass to prevent background staining and tissue loss. Slides should remain unbaked.
Limitations
Specimens must be fixed in 10% neutral buffered formalin or B plus. All other fixatives will be rejected. Fresh tissue stability is limited to ≤ 72 hours while FFPE tissues are stable indefinitely. Unstained slides also have indefinite stability. Only specimens fixed in approved fixatives will be accepted.
Methodology
Other (Anatomic Pathology)
Biomarkers
Result Turnaround Time
2 days
Related Documents
For more information, please review the documents below
Specimen
Tissue (Fresh)
Volume
Not provided
Minimum Volume
Not provided
Collection Instructions
Fixative should be at a 20:1 ratio, 10% neutral buffered formalin for 6-72 hours, 48-72 hours preferred.
Storage Instructions
Transfer specimens to 70% ethanol for longer term storage if needed.
Causes for Rejection
Specimens not fixed in 10% NBF or B plus.