Comparison of mucormycosis infection between patients with and without a history of COVID-19 infection: a retrospective cohort study

Background Mucormycosis infection is a complication seen in some coronavirus disease 2019 (COVID-19) patients. This study compares the characteristics of mucormycosis infection between COVID-19 and non-COVID-19 patients. Methods This retrospective cohort comprised 87 patients with mucormycosis divided into two groups. The first included 44 patients who had COVID-19 recently before hospitalization due to mucormycosis at Namazi Hospital, Shiraz, Iran, between February 2019 and August 2021. The second group included all 43 patients hospitalized at the same hospital due to mucormycosis between 2010 and 2019 (pre-pandemic). Results Mucormycosis patients with a history of recent COVID-19 infection had a higher rate of diabetes mellitus, fewer malignancies and higher blood glucose, erythrocyte sedimentation rate and C-reactive protein levels (p<0.05). Glucocorticoid use was common (77%) in the COVID-19 group. Conclusions In the pre-COVID-19 era, mucormycosis mainly affected immunodeficient patients like those receiving chemotherapy due to malignancy but now seems to affect COVID-19 patients with uncontrolled blood glucose and glucocorticoids use. Special care must be taken in prescribing glucocorticoids and controlling the blood glucose levels of COVID-19 patients.