Insights from Surgically treated Post Covid Acute Invasive Fungal Rhino-Orbital sinusitis in Chandrapur Study (SPAROS): A Population Based study of Coronavirus Associated Mucormycosis (CAM) characteristics in India

INTRODUCTION: Coronavirus disease 2019 (COVID-19)-associated mucormycosis (CAM) became a public health problem in India in 2021. However, information about the incidence, presentation and prognosis of CAM remains sparse. METHODS: This study describes 100 cases from the Surgically treated Post COVID Acute invasive fungal Rhino-Orbital Sinusitis in Chandrapur (SPAROS) study, a prospective observational follow-up study of patients with CAM diagnosed in Chandrapur district, India. Two-step cluster analysis using four input variables – blood glucose on admission, diabetes status, glucocorticoid exposure and severity of COVID-19 – was used to define three distinct CAM clusters. RESULTS: The incidence of CAM in the general population was 7.1 cases/1000 patients hospitalized with COVID-19. Steroid exposure and pre-existing diabetes were present in 76% and 55% of cases, respectively. At median follow-up of 18 days, only two deaths had been recorded, while 93 cases were stable. Glucocorticoids, particularly methylprednisolone, seemed to precipitate CAM. Admission to the intensive care unit appeared to be predictive of less extensive surgery. DISCUSSION: Three subtypes of CAM were identified: COVID-19-associated diabetes and mucormycosis, COVID-19-associated classical mucormycosis, and COVID-19-induced mucormycosis. A CAM hypothesis was proposed based on the dynamics of severe acute respiratory syndrome coronavirus-2 and glucose regulated protein. CONCLUSION: The clinical characteristics, natural course and pathogenesis of CAM differ from mucormycosis in the pre-COVID era. It is hoped that this classification will be useful in CAM management.