Relapse of COVID-19-associated mucormycosis in patients receiving posaconazole as maintenance treatment

Introduction: Coronavirus disease 2019 (COVID-19) has been associated with secondary fungal infections such as mucormycosis. We investigated the relapse rate of mucormycosis and its risk factors. Methodology: A prospective study was conducted on COVID-19-associated mucormycosis (CAM) patients discharged from Imam Khomeini Hospital Complex, Tehran, Iran, from July 2021 to February 2022. Patients who received posaconazole as a step-down therapy were included and examined monthly for six months. A relapsing mucormycosis case was defined as a patient with new clinical or radiological symptoms, confirmed by observing aseptate hyphae in the histopathological examination or tissue culture. The characteristics of patients with and without relapse were analyzed and compared. Results: Seventy-seven patients completed the six-month follow-up after discharge. Most patients were male (n = 46, 59.8%), with a mean age of 53.1 years (median 19-84). The most common underlying diseases were diabetes (52/77, 67.5%), hypertension (33/77, 42.8%), and cancer/chemotherapy (25/77, 32.4%). Seven patients (7/77, 9%) were reported as relapsing cases. There was no difference in demographic features and underlying diseases between the groups. A significant difference was seen in the mean duration of posaconazole consumption between patients with and without relapse (24 ± 4.4 days vs. 49.4 ± 4.3 days, respectively, p = 0.015). The primary orbital involvement was also significantly associated with relapse (p = 0.04). Conclusions: Our findings showed a significant relapse of CAM (9%). A longer duration of posaconazole consumption and completion of treatment for initial orbital involvement in CAM patients are recommended for better patient management and prevention of relapse.