Alternate Special Stains for the Detection of Mycotic Organisms in Oral Cyto-Smears-A Histomorphometric Study

In the wake of the COVID-19 pandemic, fungal infections of the maxillofacial region have become prevalent, making their accurate diagnosis vital. Histopathological staining remains a simple, cost-effective technique for differentiation and diagnosis of the causative fungal organisms. The present study aims to evaluate the staining efficacy of Periodic Acid-Schiff (PAS), Alcian Blue, Safranin-O and Gomori's Methenamine Silver (GMS) on fungal smears. This research work also attempts to study the morphometric characteristics of Candida albicans, Aspergillus flavus, Rhizopus oryzae. Candida albicans, Aspergillus flavus and Rhizopus oryzae, 10 smears each, were stained using PAS, Alcian Blue, Safranin-O and GMS. The morphological characteristics and staining efficacy were examined, and semi-quantitative scoring was performed. Candida albicans, Aspergillus flavus and Rhizopus oryzae were stained for the first time with Safranin-O. The morphometric traits were then analyzed using an image analysis software. Safranin-O provided the most reliable staining efficacy amongst the stains and optimum morphological definition for all three organisms. Safranin-O was found to be superior to PAS and GMS, ensuring detection of even the most minute mycotic colonies. The hyphae of Aspergillus flavus to be the largest, and the spores and fruiting body of Rhizopus oryzae were found to be the largest amongst the three organisms compared. Early and accurate diagnosis of fungal infections can significantly reduce morbidity in orofacial fungal infections.