Nationwide Surveillance of Antifungal Resistance of Candida Bloodstream Isolates in South Korean Hospitals: Two Year Report from Kor-GLASS

Abstract

We incorporated nationwide Candida antifungal surveillance into the Korea Global Antimicrobial Resistance Surveillance System (Kor-GLASS) for bacterial pathogens. We prospectively collected and analyzed complete non-duplicate blood isolates and information from nine sentinel hospitals during 2020−2021, based on GLASS early implementation protocol for the inclusion of Candida species. Candida species ranked fourth among 10,758 target blood pathogens and second among 4050 hospital-origin blood pathogens. Among 766 Candida blood isolates, 87.6% were of hospital origin, and 41.3% occurred in intensive care unit patients. Adults > 60 years of age accounted for 75.7% of cases. Based on species-specific clinical breakpoints, non-susceptibility to fluconazole, voriconazole, caspofungin, micafungin, and anidulafungin was found in 21.1% (154/729), 4.0% (24/596), 0.1% (1/741), 0.0% (0/741), and 0.1% (1/741) of the isolates, respectively. Fluconazole resistance was determined in 0% (0/348), 2.2% (3/135, 1 Erg11 mutant), 5.3% (7/133, 6 Pdr1 mutants), and 5.6% (6/108, 4 Erg11 and 1 Cdr1 mutants) of C. albicans, C. tropicalis, C. glabrata, and C. parapsilosis isolates, respectively. An echinocandin-resistant C. glabrata isolate harbored an F659Y mutation in Fks2p. The inclusion of Candida species in the Kor-GLASS system generated well-curated surveillance data and may encourage global Candida surveillance efforts using a harmonized GLASS system.

Keywords: Candida species; GLASS; antifungal surveillance; candidemia.

Figure 1

Number of patients with bloodstream infections (BSIs) for each target pathogen collected via the Kor-GLASS surveillance system (2010–2021). (A) Total number of BSIs caused by each target pathogen. (B) Number of hospital-origin BSIs caused by each pathogen. (C) Number of BSIs caused by each pathogen in ICU patients.

Figure 2

Overall distributions of the Candida species causing BSIs by candidemia patient age group.

Figure 3

Clinical information of cases of candidemia caused by different Candida species: sex (A), origin (hospital origin [HO] or community origin [CO]) (B) and location (ICU vs. ward) (C). In (A–C), the results are based on the 766 patients enrolled in this study. Rates of fluconazole resistance of Candida isolates recovered from the ICU and wards (D): the 729 isolates included C. albicans (n = 348), C. tropicalis (n = 135), C. glabrata (n = 133), C. parapsilosis (n = 108), and C. krusei (n = 5), for which clinical breakpoints were available in the CLSI M60. * p < 0.05 between a Candida species and all other Candida species within a given category (i.e., number of patients, sex [female vs. male], origin [HO vs. CO], or location [ICU vs. ward]). ** p < 0.05 between ICU and ward patients in the rate of fluconazole resistance according to the Candida species.