- A special stain, not an immunostain
- Substances with nearby glycol groups or their amino or alkylamino derivatives are oxidized by periodic acid to form dialdehydes, which combine with Schiff's reagent to form an insoluble magenta compound
- Used for formalin fixed tissue and enzyme cytochemistry; can be used for frozen sections with modifications (Eur J Gynaecol Oncol 1998;19:482, Am J Surg Pathol 1992;16:87)
- Stains basement membrane (normal and in tumors), glycogen, some mucins (see below) and mucopolysaccharides
- A routine stain in brain (with Luxol fast blue), cornea, kidney, liver (glycogen stains strongly for PAS without diastase) and skeletal muscle specimens for nontumor pathology
- Some mucins (see below) are PASD (PAS with predigestion with diastase) positive (i.e. stain is present after diastase predigestion; also called diastase resistant); glycogen is PASD negative (also called diastase sensitive because diastase removes PAS staining)
- PAS stains neutral and acid-simple non-sulfated and acid-complex sulfated mucins
- PAS does NOT stain acid-simple mesenchymal mucins and acid-complex connective tissue mucins
- Also stains various inclusions, bodies, granules and secretions composed of mucopolysaccharides or mucins
- Breast cytology: PASD positive cells with internal structure and producing nuclear indentation, particularly in dissociated or atypical cells, correlate with malignant histology (J Clin Pathol 2001;54:146)
- Fungi: stains fungal cell walls; PAS+ granule at anterior end of mature spores is diagnostic of microsporidia (BMC Clin Pathol 2006;6:6)
- Hematopathology: ALL, AML M5-M7 are PAS+
- Kidney: recommended for routine evaluation of renal biopsies due to basement membrane staining; also useful to diagnose renal cell carcinoma (stains glycogen, removed by diastase)
- Liver: routine stain for hepatocytes (PAS without diastase); also stains inclusions of alpha-1-antitrypsin disease
- Lung: stains amorphous or granular globules in BAL fluid in pulmonary alveolar proteinosis (J Clin Pathol 1997;50:981)
- Muscle biopsies: routine stain to demonstrate glycogen
- Pancreas: acinar cell carcinoma (PASD+)
- Parotid glands: zymogen granules are PAS+
- Prostate: Cowper’s glands are PASD+ (Am J Surg Pathol 1997;21:550)
- Skin: eosinophilic globoid bodies (Kamino bodies) in Spitz nevus are PASD+
- Small intestine: stains Whipple’s disease bacteria (Am J Clin Pathol 2002;118:742, Hum Pathol 2003;34:589); strong cytoplasmic staining present in microvillous inclusion disease versus linear brush border staining in normals (Am J Surg Pathol 2002;26:902)
- Testis: stains intratubular germ cell neoplasia (Am J Surg Pathol 1994;18:947) and seminoma (PAS+, PASD negative), but not normal seminiferous tubules
- Tumors: adenocarcinoma of various sites (mucin is PASD+), alveolar soft parts sarcoma (PASD+ crystalline structures), apocrine carcinomas, basement membrane containing tumors (cylindroma [Am J Surg Pathol 2001;25:823], eccrine spiradenoma), clear cell tumors (stains glycogen), glycogen rich carcinomas, glycogen rich/balloon cell melanoma (Arch Pathol Lab Med 1998;122:353), granular cell tumor (cytoplasmic granules), hyaline globules in renal tumors (Hum Pathol 1997;28:400), mucinous tumors, Paget’s disease of breast
- Other: stains malakoplakia
- Enzyme cytochemistry: coarse granular staining
Courtesy of Andrey Bychkov, M.D., Ph.D.
Graves disease
PAS-D staining of PTC with laryngeal invasion
PAS staining of thyroid
Kidney:
Nodular glomerulosclerosis
Case of the Week #51:
Tubulocystic carcinoma, kidney (tumor)
Images hosted on other servers:
Bacteria:
Atypical mycobacteria
Rhodococcus PAS+, colonic histiocytes
Rhodococcus PAS+, pulmonary histiocytes
Tropheryma whipplei histiocytes, hippocampus
CNS:
Acquired hepatocellular degeneration
Secretory meningioma
CNS:
Malakoplakia
Cornea:
Fuch's dystrophy
Fungi:
Blastomyces
Candida of esophagus
Lung
Tongue
Coccidioidis immitis, tongue
Cryptococcal meningitis
Histoplasmosis, colon, HIV+ woman
Microsporidia
Mucor of stomach
Heart:
Glycogen storage disease
Kidney:
Normal
Alport syndrome
Alport syndrome, fetal glomerulus
Amyloidosis
Chronic pyelonephritis
Dense deposit disease
Fabry's disease
Focal segmental glomerulosclerosis
Henoch Schoenlein purpura
IgA nephropathy
Immunotactoid glomerulonephritis
Membranoproliferative glomerulonephritis type I
With crescent
Doubling of capillary wall
Nephronophthisis
Nodular glomerulosclerosis
SLE
Thrombotic microangiopathy
Liver:
Alpha1 antitrypsin deficiency
Hepatitis A with confluent necrosis
Lung:
Pneumocystis pneumonia
Pulmonary alveolar proteinosis
Hyaline membrane disease
Parasites:
Acanthamoeba histolytica
Echinococcus, bone
Parotid gland:
Normal
Skeletal muscle:
AS+ diastase sensitive material in McArdle’s disease
Skin:
Fabry disease
Small intestine:
Various images
Tumors:
Acinar cell carcinoma, pancreas
Adenocarcinoma, colon
Alveolar soft parts sarcoma in cervix
Clear cell acanthoma
Clear cell carcinoma, ovary
Cylindroma
Eccrine spiradenoma
Ewing sarcoma
Glycogen rich carcinoma, breast
Granular cell tumor
Kaposi sarcoma
Lymphoplasmacytic lymphoma
Mucinous cystadenoma, ovary
Secretory meningioma
- Basement membrane, fungi, glycogen (removed after diastase or amylase predigestion), mucins (neutral and acid-simple non-sulfated and acid-complex sulfated types), surfactant
- ALL (75%, block staining), alpha-1-antitrypsin inclusions, alveolar soft part sarcoma (intracytoplasmic crystals), AML-M5a, M6 (60%), M7, basement membrane containing tumors (cylindroma), clear cell tumors, malakoplakia, renal cell carcinoma (PAS+ glycogen removed with diastase), parasites
- Mucins (acid-simple mesenchymal and acid-complex connective tissue types)
