Grocott-Gomori’s Methenamine Silver Staining


The main objectives of Grocott-Gomori’s Methenamine Silver Staining are:

  • To demonstrate the presence of fungi in a given sample, such as tissue sections, smears, or aspirates.
  • To demonstrate the presence of specific fungal species that cause opportunistic infections in immunocompromised or immunosuppressed patients, such as Pneumocystis jiroveci and Histoplasma spp.

Fungi are eukaryotic microorganisms that have a cell wall composed of polysaccharides, such as chitin and glucan. These polysaccharides can be detected by using silver and methenamine, which are the main components of Grocott-Gomori’s Methenamine Silver Staining. This staining technique is based on the principle of argentaffin reaction, which is the ability of some cells to reduce silver ions to metallic silver, forming a black precipitate. By using this staining technique, fungal cells can be visualized as black structures against a pale green background.

Grocott-Gomori’s Methenamine Silver Staining is a popular and sensitive method for identifying fungal organisms in histology and microbiology. It can differentiate various fungal morphologies, such as hyphae, spores, yeast-like cells, and arthroconidia. It can also distinguish fungal cells from bacterial cells, which do not stain with this technique. Moreover, it can identify some fungi that are difficult to detect by other methods, such as Pneumocystis jiroveci and Histoplasma spp. These fungi are known to cause pneumonia and systemic infections in patients with impaired immunity, such as those with HIV/AIDS, cancer, organ transplantation, or corticosteroid therapy.

Therefore, Grocott-Gomori’s Methenamine Silver Staining is a useful and reliable technique for demonstrating the presence and diversity of fungi in various samples and for diagnosing fungal infections in clinical settings.