methenamine-silver stain

Indications

• detection of Pneumocystis carinii & fungi: (Groscott-Gomori's methamine-silver) modification in which sections are pretreated with chromic acid prior to addition of methenamine-silver
• identification of argentaffin cells; used in combination with gold chloride, sodium thiosulfate & safranin
• urates: warm sections are treated directly with hot methemanine-sliver
• melanin

Laboratory

• cell wall of Pneumocystis & fungi appear brown-black against a green background
• argentaffin granules appear brown-black against a green background
• urates appear black
• melanin reduces silver nitrate -> black precipitate

More general terms

• microbiologic stain
• tissue stain

More specific terms

• microscopic observation in tissue by methenamine silver stain