Isolation of fungi from the Trichosporonaceae family in urine samples from COVID-19 patients: Should we worry about it?

Abstract

Background: Trichosporon genus encompasses emergent fungal pathogens with an increased incidence that concerns potential multi-drug resistance and mortality, especially in immunocompromised patients. COVID-19 is a disease of pandemic proportions with complications related to cytokine storm and lymphopenia.

Aims: To study the isolation of fungi within the Trichosporanaceae family in patients infected with SARS-CoV-2.

Methods: In this work we recovered 35 fungal isolates belonging to the Trichosporonaceae family from urine samples of 32 patients hospitalized due to COVID-19 complications. We evaluated their mycological characteristics, as well as the patient's clinical aspects.

Results: Trichosporon asahii was the main species identified, followed by Cutaneotrichosporon jirovecii and Trichosporon inkin, respectively. The blood cultures of 20 of these patients were all negative for fungi. Isolation of Trichosporonaceae fungi in urine was associated with high COVID-19 severity. The antifungal susceptibility test showed low MIC values for voriconazole, an antifungal in the first-line treatment of trichosporonosis. In contrast, high MIC values were found in the case of amphotericin B and 5-fluorocytosine in all the species, except for C. jirovecii. Since invasive trichosporonosis was not confirmed, none of the patients were given an antifungal treatment, without affecting the outcome of the patients.

Conclusions: Our results suggest that the isolation in urine of fungi from the Trichosporonaceae family may be associated to more severe forms of the disease COVID-19, but not with an increase in death rate. However, these isolates do not seem to be linked to urinary infections, therefore no antifungal therapy is mandatory in these cases.