Silver Methenamine PASM Kit
Basement Membrane Stain — GMS for Fungi
Silver Methenamine (PASM) Kit
The Periodic Acid-Silver Methenamine (PASM) technique, also known as Grocott's Methenamine Silver (GMS), is the gold standard for demonstrating basement membranes and detecting fungi in tissue sections. This method oxidizes carbohydrate groups with periodic acid, then deposits silver methenamine onto these sites. PASM is essential in renal pathology for visualizing glomerular basement membranes (GBM) and detecting immune complex deposits. In microbiology, GMS is superior to PAS for detecting fungal organisms including Pneumocystis jirovecii, Aspergillus, and Candida species. The stain produces crisp black outlines of basement membranes against a pale green background.
PASM Staining Results
Basement Membranes
GBM, tubular basement membranes, and capillary walls stain black with crisp outlines. Critical for renal pathology.
Fungal Organisms
Yeasts, molds, and Pneumocystis cyst walls stain black. Superior sensitivity for detecting fungal infections in tissue.
Background
Light green or gold counterstain provides excellent contrast. Nuclei may appear brown if hematoxylin is used.
Clinical Applications
Essential for renal biopsy interpretation, fungal infection diagnosis, and evaluating basement membrane diseases.
Complementary Stains
Need Special Stain Kits?
Contact our team for specifications, protocols, and availability.