Medical Science: Updates and Prospects Vol. 10

Background: Fungal infections are among the most dangerous infectious diseases, and their diagnosis is often challenging. Delays in diagnosis can postpone treatment and endanger patient survival. Mucormycosis became increasingly common during the COVID-19 pandemic. Histopathology remains the gold standard for diagnosis, and fungal culture is confirmatory, but both are time-consuming. Frozen sections offer rapid intraoperative diagnosis, enabling early management.

Aim: This study aims to evaluate the utility and diagnostic accuracy of frozen section in detecting Mucormycosis, to determine the age groups commonly affected, and to identify any associated comorbidities.

Materials and Methods: This prospective study was conducted over 18 months (January 2021 – June 2022) in the Department of Pathology of a tertiary care hospital. Seventy-six patients with suspected mucormycosis, whose specimens underwent both frozen section and formalin-fixed paraffin-embedded (FFPE) histopathological examination, were included. Frozen sections were performed using a cryostat at −20°C to −30°C. Sections were stained with hematoxylin and eosin using a rapid method and examined microscopically. Reports were delivered intraoperatively within 20–25 minutes to guide surgical management. The remaining tissue was processed for standard histopathology.

Result and Analysis: Among the 76 specimens, 56 (74%) were positive for fungus on frozen section, identified by aseptate broad hyphae with right-angle branching. Of the 20 frozen section-negative specimens, 6 were found to be positive on FFPE histopathology (false negatives), and 1 frozen section-positive specimen was negative on FFPE (false positive). The diagnostic performance of frozen sections showed a sensitivity of 91%, specificity of 93.7%, accuracy of 91.5%, positive predictive value (PPV) of 98%, and negative predictive value (NPV) of 70%.  

Conclusion: Frozen section is a highly useful and rapid diagnostic tool for mucormycosis, with high sensitivity and specificity. The assessment of margins of the lesions by the frozen section intraoperatively during debridement is very important for further management of the patient.