In the COVID-19 pandemic, COVID 19 patients were found to have immunosuppression resulting in diverse range of bacterial and fungal infections that may be associated with preexisting comorbidities. Fungal rhinosinusitis is an emerging concern in post COVID-19 patients which needs prompt treatment for better outcome of the patients.
Design: Out of 180 sinonasal tissues received from post COVID-19 patients, fungal infection was detected in 110 cases. Tissue processing was done after overnight fixing the tissue in 10% formalin. Decalcification was done wherever required. Routine H&E slide staining was done, and histopathological findings were noted. Clinicopathological correlation was done, and results were compared to other studies.
Results and Discussion: 110 cases were diagnosed with fungal infections histopathologically of which 4 cases were having non-invasive fungal infection and rest  were invasive. Based on morphology of fungal hyphae on microscopy, 99 cases were suggestive of mucormycosis, followed by 8 cases of suspected aspergillosis and remaining 3 cases with combined infection. The most common involvement in our study was maxillary sinus. Orbital extension of fungal infections was found in 20 cases out of 110 cases in the present study.
Conclusion: In the post-COVID-19 patients, the symptoms like facial pain, cheek swellings, orbital pain, nasal discharge should be evaluated properly for possibility of fungal infections that may prove fatal if undiagnosed. Early diagnosis is essential for initiation of anti-fungal treatment and limit the invasive course of the disease.