title: In vitro fluconazole and voriconazole susceptibilities of Candida bloodstream isolates in Korea: use of the CLSI and EUCAST epidemiological cutoff values.
abstract: BACKGROUND
  At present, the clinical breakpoints (CBPs) of both fluconazole and voriconazole are available only for 3 common Candida species in the Clinical and Laboratory Standards Institute (CLSI) and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) methods. Epidemiological cutoff values (ECVs) were recently applied to both methods to detect the emergence of acquired resistance (i.e., non-wild-type isolates) among 5 common Candida species.
  
  
  METHODS
  We performed a nationwide study to determine the fluconazole and voriconazole susceptibility of Candida bloodstream isolates (BSIs) using both the CLSI and EUCAST methods. A total of 423 BSIs of 5 Candida species were collected from 8 hospitals. The azole susceptibilities were assessed on the basis of the species-specific CBPs and ECVs.
  
  
  RESULTS
  Of the 341 BSIs of 3 common Candida species (i.e., C. albicans, C. tropicalis, and C. parapsilosis), 0.3% and 0.9%, 0.0% and 1.5% of isolates were categorized as fluconazole and voriconazole resistant according to the CLSI and EUCAST CBPs, respectively. Of 423 total BSIs, 1.4% and 2.6% had fluconazole minimum inhibitory concentrations (MICs) exceeding the ECVs according to the CLSI and EUCAST, respectively; 1.0% and 2.1% had voriconazole MICs exceeding the ECVs according to the CLSI and EUCAST, respectively. Categorical agreement between the methods using ECVs was 98.3% for fluconazole and 98.3% for voriconazole.
  
  
  CONCLUSIONS
  The EUCAST and CLSI methods using ECVs provide highly concordant results. Moreover, non-wild-type isolates with possibly acquired azole resistance were rare among the BSIs of 5 common Candida species in Korea.
authors.affiliation: Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju, Korea.
authors.forename: Min Joong
authors.initials: MJ
authors.lastname: Jang
authors.forename: Jong Hee
authors.initials: JH
authors.lastname: Shin
authors.forename: Wee Gyo
authors.initials: WG
authors.lastname: Lee
authors.forename: Mi-Na
authors.initials: MN
authors.lastname: Kim
authors.forename: Kyungwon
authors.initials: K
authors.lastname: Lee
authors.forename: Hye Soo
authors.initials: HS
authors.lastname: Lee
authors.forename: Mi-Kyung
authors.initials: MK
authors.lastname: Lee
authors.forename: Chulhun L
authors.initials: CL
authors.lastname: Chang
authors.forename: Hee-Chang
authors.initials: HC
authors.lastname: Jang
authors.forename: Eun Song
authors.initials: ES
authors.lastname: Song
authors.forename: Soo Hyun
authors.initials: SH
authors.lastname: Kim
authors.forename: Myung-Geun
authors.initials: MG
authors.lastname: Shin
authors.forename: Soon-Pal
authors.initials: SP
authors.lastname: Suh
authors.forename: Dong-Wook
authors.initials: DW
authors.lastname: Ryang
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D002175:Candida / Q000187:drug effects* / Q000302:isolation & purification; D002177:Candidiasis / Q000453:epidemiology / Q000382:microbiology; D025141:Drug Resistance, Fungal / Q000187:drug effects; D015725:Fluconazole / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D011743:Pyrimidines / Q000494:pharmacology*; D056910:Republic of Korea; D014230:Triazoles / Q000494:pharmacology*; D065819:Voriconazole
chemical_list: D000935:Antifungal Agents; D011743:Pyrimidines; D014230:Triazoles; D015725:Fluconazole; D065819:Voriconazole
keywords: CLSI; Candida; EUCAST; Fluconazole; Voriconazole; epidemiological cutoff value