Candidiasis in COVID-19 patients: a literature review

The COVID-19 infection has led to a surge in secondary mycoses. Patients with COVID-19 have many risk factors that contribute to the development of mycoses: viral immunosuppression, severe lung damage, intensive care unit (ICU), venous catheters, invasive ventilation, antibiotic therapy, glucocorticosteroids and anticytokine therapy. Various mycoses have been diagnosed in patients with COVID-19: candidiasis, aspergillosis, mucormycoses, etc. Candidiasis was the most common mycosis in COVID-19 patients, while invasive candidiasis became a serious problem in ICU patients and was accompanied by high mortality. During the pandemic, along with C. albicans, “non-albicans” Candida species have become significant: C. glabrata, C. tropicalis, C. parapsilosis and C. krusei. Clinical manifestations of candidiasis are nonspecific and can be regarded as manifestations of COVID-19 or a secondary bacterial infection. For specific diagnostics of candidiasis, cultural and non-cultural research methods are used (PCR, determination of (1,3)-β-D-glucan, mannan antigen and antibodies to mannan). Diagnostics of invasive candidiasis is based on the isolation of the pathogen from biopsies, tissue aspirates or normally sterile fluids (cerebrospinal fluid, blood, etc.). Therapy for invasive candidiasis requires an integrated approach: elimination of possible risk factors, replacement of vascular catheters, antifungal therapy. There are problems of resistance of clinical strains of Candida to antifungal drugs, which should be taken into account when prescribing empirical antifungal therapy. The aim of this review is to systematize the available literature data on the prevalence, clinical manifestations, diagnosis and treatment of candidiasis in COVID-19 patients.