Yeasts from blood cultures in the wake of the COVID-19 pandemic in a tertiary care hospital: Shift in species epidemiology, steady low antifungal resistance and full in vitro ibrexafungerp activity.

Abstract

Several institutions reported a rise not only in fungemia incidence but also in the number of cases caused by Candida auris or fluconazole-resistant C. parapsilosis during the COVID-19 pandemic. Since the pandemic broke out in early 2020, we studied its impact on fungemia incidence, species epidemiology, potential patient-to-patient transmission, and antifungal resistance in 166 incident yeast isolates collected from January 2020 to December 2022. Isolates were molecularly identified, and their antifungal susceptibilities to amphotericin B, azoles, micafungin, anidulafungin, and ibrexafungerp were studied following the European Committee on Antimicrobial Susceptibility Testing (EUCAST) method, and genotyped. The fungemia incidence (episodes per 1000 admissions) tended to decrease over time (2020=1.60, 2021=1.36, 2022=1.16); P>.05). Species distribution was C. albicans (50.6%, n=84), C. parapsilosis (18.7%, n=31), C. glabrata (12.0%, n=20), C. tropicalis (11.4%, n=19), C. krusei (3.0%, n=5), other Candida spp. (1.2%, n=2), and non-Candida yeasts (3.0%, n=5). The highest and lowest proportions of C. albicans and C. parapsilosis were detected in 2020. The proportion of isolates between 2020 and 2022 decreased in C. albicans (60.3% vs. 36.7%) and increased in C. parapsilosis (10.3% vs. 28.6%; P<.05) and C. tropicalis (8.8% vs. 16.3%; P>.05). Only three C. albicans intra-ward clusters involving two patients each were detected, and the percentages of patients involved in intra-ward clusters reached 9.8% and 8.0% in 2020 and 2021, respectively, suggesting that clonal spreading was not uncontrolled. Fluconazole resistance (5%) exhibited a decreasing trend (P>.05) over time (2020=7.6%; 2021=4.2%; and 2022=2.1%). Ibrexafungerp showed high in vitro activity.