Candidiasis in patients with COVID-19: a review

Coronavirus infection (COVID-19) has led to an increase in the incidence of secondary fungal infections. Patients with COVID-19 have multiple risk factors contributing to their development, including virus-induced immunosuppression, severe lung damage, admission to intensive care units, presence of venous catheters, invasive mechanical ventilation, and treatment with antibiotics, glucocorticoids, and anticytokine agents. Various fungal infections have been diagnosed in patients with COVID-19, including candidiasis, aspergillosis, mucormycosis, and others. However, candidiasis has been the most prevalent mycosis, with its invasive form becoming a serious concern in intensive care unit patients due to its high mortality rate. During the pandemic, in addition to Candida albicans, non-albicans species such as C. glabrata, C. tropicalis, C. parapsilosis, and C. krusei gained clinical significance. The clinical manifestations of candidiasis are nonspecific and are often misinterpreted as symptoms of COVID-19 or signs of secondary bacterial infection. Specific diagnosis of candidiasis involves both culture-based and non-culture-based methods (polymerase chain reaction, detection of (1,3)-β-D-glucan, mannan antigen, and anti-mannan antibodies). The diagnosis of invasive candidiasis is based on the isolation of the pathogen from biopsy samples, tissue aspirates, or normally sterile body fluids (cerebrospinal fluid, blood, etc). Treatment requires a comprehensive approach, including the elimination of possible risk factors, replacement of vascular catheters, and administration of antifungal agents. Resistance of clinical Candida strains to antifungal drugs remains an issue and should be considered when initiating empirical antifungal therapy.

This review summarizes current resources on the prevalence, clinical manifestations, diagnosis, and treatment of candidiasis in patients with COVID-19.