Antifungal Susceptibility Patterns and Epidemiological Distribution of Clinical Fungal Isolates Recovered from Inpatients During the COVID-19 Pandemic Period at a University Hospital in Istanbul
Abstract
Candida species remain the most prevalent pathogens in nosocomial fungal infections. However, invasive infections caused by non-Candida opportunistic fungi, have emerged as a significant concern, particularly in immunocompromised patients. The widespread use of antifungal agents in intensive care units (ICUs) further accelerates the development of resistant species. This retrospective study aimed to evaluate the species distribution and antifungal susceptibility of fungi isolated from various clinical samples at a university hospital in Istanbul during the Corona virus Disease 19 (COVID-19) pandemic (2020–2022). Isolates were identified using germ tube testing and the VITEK 2 Compact® system. Susceptibility was tested against fluconazole, voriconazole, caspofungin, micafungin, amphotericin B, and flucytosine. A total of 279 isolates were obtained from 243 patients, with 66% (n=185) originating from the ICU. Urine was the most frequent specimen type (48%). Candida species accounted for 94% (n=264) of the isolates, while 6% (n=15) were non-Candida species. The findings revealed that Candida albicans exhibited the highest resistance to voriconazole (12.3%). Notably, 37.5% of Cryptococcus laurentii isolates displayed elevated minimum inhibitory concentration (MIC) values to both caspofungin and micafungin. Furthermore, Trichosporon asahii demonstrated concerningly high MICs in 71.4% of the isolates to fluconazole, caspofungin, and micafungin. Increasing fungal infection frequency, rising Candida resistance, and elevated MIC profiles in rare species pose critical clinical challenges. Continuous monitoring of local susceptibility and MIC patterns is essential to mitigate the high mortality and morbidity associated with fungal pathogens during and after pandemic periods. These results highlight the urgent need for surveillance.
Keywords
Antifungal, Candida, Cryptococcus, nosocomial infection, Trichosporon
Ethical Statement
The study was conducted in accordance with the principles of the Declaration of Helsinki. Ethics committee approval was obtained from the Biruni University Non-Interventional Ethics Committee (Date: 14.06.2023, Decision No: 2023/81-03).
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