Mucormycosis in COVID-19 pandemic and its neurovascular spread

PURPOSE: Rhinocerebral mucormycosis is a rapidly progressive angioinvasive fungal infection commonly seen in diabetics. In the COVID-19 pandemic we have witnessed a sudden surge in these cases. We aimed to evaluate the disease presentation, patterns of spread, and any association with the COVID-19 virus. METHODS: This prospective study was conducted on mucormycosis patients operated between March and July 2021. The diagnosis was confirmed either on KOH staining, fungal culture or histopathological examination. RESULTS: Thirty one cases (21 males, 10 females) with a mean age of 53.3 years were included, of which 9 (29.1%) were COVID positive on presentation, 17 (54.8%) were post-COVID, while 5 (16.1%) had radiological evidence of COVID sequelae. Most common symptoms were cheek numbness (87.1%), headache (83.9%), visual disturbances (77.4%), and palate involvement (58.1%). Blackening of turbinates was uncommon (22.6%). Ethmoid sinus was involved in all patients. Pterygopalatine fossa involvement was present in 77.4%, and was accurately diagnosed on contrast enhanced MRI scan. There were 8 (25.8%) deaths, while the remaining are discharged or under treatment. CONCLUSION: An increase in the incidence of mucormycosis in the COVID-19 pandemic is probably due to a compromise in host immunity along with a synergistic effect in thrombotic microangiopathy. Spread of infection to the soft tissues of the infratemporal fossa, orbit or palate occur via neurovascular structures rather than by bone erosion. The pterygopalatine fossa is involved in most individuals.