Species distribution and antifungal susceptibility of Candida isolates from sterile body sites: a 14-year retrospective study at a tertiary care hospital in China (2010-2023).

BACKGROUND

Invasive candidiasis (IC) remains a major cause of morbidity and mortality worldwide, particularly among critically ill and immunocompromised patients. The emergence of antifungal resistance, especially to azoles, has complicated empirical and targeted therapy. Continuous, region-specific surveillance of Candida species distribution and antifungal susceptibility patterns is therefore essential.

METHODS

We conducted a retrospective observational study of IC cases at Nanjing Drum Tower Hospital, a tertiary care center in eastern China, from January 2010 to December 2023. Candida isolates recovered from sterile body sites were identified to the species level. Antifungal susceptibility testing was performed using standardized commercial platforms, and results were interpreted according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Species distribution, temporal trends, ward-specific patterns, and antifungal susceptibility profiles were analyzed.

RESULTS

A total of 1,038 non-duplicate Candida isolates were included. Candida albicans was the predominant species (51.1%), followed by C. parapsilosis (15.8%), C. tropicalis (15.5%), and C. glabrata (11.3%). Ascitic fluid (44.5%) and blood (38.2%) were the most common specimen sources, with most isolates originating from the intensive care unit and general surgery wards. Over the 14-year period, the proportions of C. albicans and C. glabrata increased significantly, whereas C. parapsilosis declined. Overall resistance rates to fluconazole and voriconazole were relatively low (3.0% and 2.9%, respectively). However, C. tropicalis exhibited higher azole resistance and non-wild-type phenotypes, particularly to posaconazole. Echinocandin and amphotericin B resistance was rare across major species.

CONCLUSIONS

In this tertiary-care hospital, C. albicans remained the most frequently isolated Candida species from sterile body sites, whereas C. tropicalis demonstrated the highest azole resistance burden. These findings highlight the importance of sustained local surveillance to inform empirical antifungal strategies.