Abstract / Summary
Candidemia is a growing global problem in recent years. Diagnostic problems, high mortality, and antifungal resistance increase the importance of the issue. Candida species, such as Candidozyma auris , are also noteworthy for their high MIC values against antifungal drugs and their ability to cause outbreaks in hospitals. There is insufficient information regarding the clinical significance, antifungal susceptibility, and treatment approaches of newly identified Candida species. This study evaluated the distribution and antifungal susceptibility of rare Candida species, identified as causative agents of candidemia, in a tertiary university hospital. Candida isolates cultured from blood samples at a single center over a nine-year period (2015–2023) were included in the study. Candida isolates were identified at the species level using phenotypic methods, API 20 C AUX, BD Phoenix YEAST ID and/or MALDI-TOF MS. Antifungal susceptibility testing (fluconazole, voriconazole, itraconazole, anidulafungin, micafungin, amphotericin-B) was performed using the gradient test with manufacturer recommendations, and MIC50-90 values were determined. A total of 541 Candida isolates were included in the study. C.albicans ( n = 214, 39.5%), C.parapsilosis ( n = 164, 30%), C.glabrata ( n = 47, 8.7%), C.tropicalis ( n = 42, 7.7%), and C.krusei ( n = 10, 2%) were the most frequently detected isolates, while among rare Candida isolates ( n = 55, 10%), the three most frequently detected species were Clavispora lusitaniae ( n = 9, 1.6%), Yarrowia lipolytica ( n = 7, 1.3%), and Kluyveromyces marxianus ( n = 7, 1.3%). Despite generally low MIC values in most isolates, high MIC values were detected to the tested azoles, including fluconazole (MIC > 32 µg/mL) in C.inconspicua ( n = 4, 0.7%) and fluconazole, voriconazole, itraconazole (MIC > 32 µg/mL) in C.blankii ( n = 2, 0.4%); this underscores the need for accurate species identification and antifungal susceptibility testing. Candidemia caused by rare Candida isolates may have a different course than cases caused by classic candidemia agents. Therefore, more comprehensive studies are needed to standardize the species-level characterization of the detected isolate and to improve antifungal susceptibility testing.