Diabetes Mellitus and Glucocorticoid Use As Risk Factors for COVID-19 Associated Mucormycosis

Background: A surge of cases of Coronavirus Disease 2019 (COVID-19)-Associated Mucormycosis (CAM) was recently observed. Objective: To determine the contribution of diabetes and glucocorticoid therapy in predisposing to CAM. Methods: Pubmed search until July 2nd, 2021. Search terms included mucormycosis, diabetes, glucocorticoids, corticosteroids, coronavirus disease 2019, mortality. Randomized trials, case series, retrospective, pre-print studies, meta-analysis, professional guidelines are reviewed. Pertinent in vitro and animal studies are also included. Results: Diabetes mellitus was reported in 78-85% of cases of CAM worldwide, with the highest rates present in India. Diabetic Ketoacidosis (DKA) was observed in 3.5-41% of cases of CAM. Glucocorticoid therapy emerged as another predisposing factor occurring in 85% of cases of CAM. Injudicious use of glucocorticoids may be a contributing factor in a substantial proportion of subjects with CAM. Majority of patients develop symptoms of CAM between day 10 and 15 from the diagnosis of COVID-19. However, some cases of CAM may present up to 3 months after COVID-19 or following recovery from COVID-19. Mortality rates of CAM overall ranges from 34-48%. Surgical debridement may be associated with improved survival. Conclusions: High index of suspicion for CAM should be present in patients with diabetes and those receiving corticosteroids. Effective glycemic control and judicious use of glucocorticoids should be implemented to decrease incidence of CAM.