Description
Why It’s Done:
The PAS test on blood or bone marrow is used to:
• Diagnose or classify leukemia (especially ALL and AML) by identifying the presence of PAS-positive leukemic cells.
• Detect abnormal storage of glycogen or other polysaccharides in blood or marrow cells.
• Identify fungal infections, although this is more common with PAS staining in tissue biopsies.
• Support diagnosis of certain bone marrow or metabolic storage disorders.
• Help differentiate between various types of anemias and myeloproliferative disorders.
Preparation:
• No specific preparation is typically needed for this test.
• Fasting is not required.
• Let your doctor know about any ongoing medications or medical conditions, especially if you are being treated for a hematologic disorder.
• The sample is obtained through:
o Bone marrow aspiration/biopsy (usually from the hip bone) performed under local anesthesia.
o Or, in some cases, a blood sample may be used if indicated by your physician.
• Follow any pre-procedural instructions if a bone marrow biopsy is planned, such as arranging for someone to accompany you post-procedure.
