Fungal Rhinosinusitis: Study of Risk Factors, Outcome and Utility of Nasal Samples in Its Diagnosis

Background and Aim: Fungal rhinosinusitis (FRS) sets in following interactivity of fungi with Sino nasal tract when immune system is subdued. Due to varied clinical presentation of FRS with inconclusive evidence of imaging, mycological evaluation helps to identify and speciate the fungi .FRS can be diagnosed with biopsy tissue and/or deep nasal swabs. This study was undertaken to know risk factors, outcome along with utility of nasal samples with emphasis on deep nasal swabs in diagnosing fungal rhinosinusitis. Materials and Methods: A retrospective observational study was carried out on patients with suspected fungal rhinosinusitis (invasive and non-invasive). Both COVID 19 positive and negative patients by RT-PCR were included. Brief clinical history, associated comorbidities, risk factors and outcome were noted in these cases.  Nasal swabs or tissue sample from endoscopic biopsy obtained from patients were subjected to Gram stain, KOH mount and culture on Sabouraud dextrose agar followed by slide culture for identification. Results: Of the 41 cases studied for FRS, 25 were males and 16 females. Risk factors like Post COVID-19 infection was seen in 27(65.8%), diabetes in 31(75.6%) and use of steroid during COVID-19 treatment in 16(39.02%) cases. Deep nasal swabs were received in 29(70.7%) and tissue obtained after debridement in 12(29.3%) cases. Rhizopus spp was the most common fungi isolated followed by Aspergillus spp. Conclusion: Both COVID and non-COVID patients were diagnosed with invasive/ non-invasive fungal rhinosinusitis from deep nasal swabs/tissue in the present study. Diabetes was an important comorbidity in non-COVID patients with FRS. Deep nasal swabs aided early diagnosis for both invasive and non-invasive FRS.