Journal of Cytology

: 2019  |  Volume : 36  |  Issue : 3  |  Page : 184-

Grocott methenamine silver positivity in Neutrophils

Amit Kumar Adhya 
 Department of Pathology and Lab Medicine, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India

Correspondence Address:
Dr. Amit Kumar Adhya
Department of Pathology and Lab Medicine, All India Institute of Medical Sciences, Bhubaneswar, Odisha

How to cite this article:
Adhya AK. Grocott methenamine silver positivity in Neutrophils.J Cytol 2019;36:184-184

How to cite this URL:
Adhya AK. Grocott methenamine silver positivity in Neutrophils. J Cytol [serial online] 2019 [cited 2019 Dec 9 ];36:184-184
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Grocott methenamine silver (GMS) stain is commonly used for the identification of fungi on cytosmears and tissue sections. It imparts a black color to the fungal profiles and a pale green color to the background. It stains all pathogenic and nonpathogenic fungi and melanin. Mucins and glycogen may also be stained as dark brown colored structures. We routinely perform GMS stain in our lab using the standard procedure and reagents.[1] We have observed that the cytoplasm of neutrophils in the smear take up the black color. [Figure 1]a and [Figure 1]b The black stained neutrophils may be mistaken for yeast forms of fungus. On a casual look the black stained neutrophils may be confused with pneumocystis during evaluation of bronchoalveolar lavage fluid. Careful evaluation of the cell will reveal the unstained lobated nuclei of the neutrophils, whereas the organism will show typical “cup and saucer” appearance. [Figure 1]c and [Figure 1]d On the other hand, neutrophils may also serve as a positive internal control to ensure the quality of the stain. Other pitfalls of Grocott stain include its aberrant staining in nonfungal organisms such as the internal organs of Strongiloides stercoralis larvae, in the intranuclear inclusions of Cytomegalovirus infected cells, endospores of Bacillius cereus, and surface of Nocardia[2]. Awareness of these facts is essential to avoid misdiagnosis.{Figure 1}

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1Morris GB, Ridgway EJ, Suvarna SK. Traditional stains and modern techniques for demonstrating microorganisms in histology. In: Suvarna SK, Layton C, Bancroft JD, editors. Bancroft's Theory and Practice of Histological Techniques. 8th ed. Elsevier. 2018. p. 267.
2Wright MA, Mody DR, Anton RC, Schwartz MR. Aberrant staining with Grocott's methenamine silver: utility beyond fungal organisms. J Am Soc Cytopathol 2017;6:223-7.