title: Rapid antifungal susceptibility determination for yeast isolates by use of Etest performed directly on blood samples from patients with fungemia.
abstract: We prospectively determined the antifungal susceptibility of yeast isolates causing fungemia using the Etest on direct blood samples (195 prospectively collected and 133 laboratory prepared). We compared the Etest direct (24 h of incubation) with CLSI M27-A3 and the standard Etest methodologies for fluconazole, voriconazole, posaconazole, isavuconazole, caspofungin, and amphotericin B. Strains were classified as susceptible, resistant, or nonsusceptible using CLSI breakpoints (voriconazole breakpoints were used for posaconazole and isavuconazole). Categorical errors between Etest direct and CLSI M27-A3 for azoles were mostly minor. No errors were detected for caspofungin, and high percentages of major errors were detected for amphotericin B. For the azoles, false susceptibility (very major errors) was found in only two (0.6%) isolates (Candida tropicalis and C. glabrata). False resistance (major errors) was detected in 46 (14%) isolates for the three azoles (in 23 [7%] after excluding posaconazole). Etest direct of posaconazole yielded a higher number of major errors than the remaining azoles, especially for C. glabrata, Candida spp., and other yeasts. Excluding C. glabrata, Candida spp., and other yeasts, the remaining species did not yield major errors. Etest direct for fluconazole, voriconazole, isavuconazole, and caspofungin shows potential as an alternative to the CLSI M27-A3 procedure for performing rapid antifungal susceptibility tests on yeast isolates from patients with fungemia. Etest direct is a useful tool to screen for the presence of azole-resistant and caspofungin-nonsusceptible strains.
authors.affiliation: Clinical Microbiology and Infectious Diseases Department, Hospital General Universitario Gregorio Marañón, Universidad Complutense de Madrid, Madrid, Spain. jguineaortega@yahoo.es
authors.forename: Jesús
authors.initials: J
authors.lastname: Guinea
authors.forename: Sandra
authors.initials: S
authors.lastname: Recio
authors.forename: Pilar
authors.initials: P
authors.lastname: Escribano
authors.forename: Marta
authors.initials: M
authors.lastname: Torres-Narbona
authors.forename: Teresa
authors.initials: T
authors.lastname: Peláez
authors.forename: Carlos
authors.initials: C
authors.lastname: Sánchez-Carrillo
authors.forename: Marta
authors.initials: M
authors.lastname: Rodríguez-Créixems
authors.forename: Emilio
authors.initials: E
authors.lastname: Bouza
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D003951:Diagnostic Errors / Q000706:statistics & numerical data; D016469:Fungemia / Q000382:microbiology*; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods; D015003:Yeasts / Q000187:drug effects*
chemical_list: D000935:Antifungal Agents
references.citation: J Clin Microbiol. 2009 Sep;47(9):2766-71
references.pmid: 19571029
references.citation: Diagn Microbiol Infect Dis. 1994 Oct;20(2):81-6
references.pmid: 7867309
references.citation: Clin Infect Dis. 2006 Jul 1;43(1):25-31
references.pmid: 16758414
references.citation: J Clin Microbiol. 2006 Mar;44(3):819-26
references.pmid: 16517860
references.citation: Clin Microbiol Rev. 2007 Jan;20(1):133-63
references.pmid: 17223626
references.citation: Antimicrob Agents Chemother. 2002 Aug;46(8):2477-81
references.pmid: 12121921
references.citation: J Clin Microbiol. 2005 Apr;43(4):1829-35
references.pmid: 15815004
references.citation: Clin Microbiol Rev. 2006 Apr;19(2):435-47
references.pmid: 16614256
references.citation: J Clin Microbiol. 2003 May;41(5):1875-80
references.pmid: 12734220
references.citation: Antimicrob Agents Chemother. 2005 Sep;49(9):3640-5
references.pmid: 16127033
references.citation: Antimicrob Agents Chemother. 2008 Apr;52(4):1396-400
references.pmid: 18212101
references.citation: Antimicrob Agents Chemother. 2003 May;47(5):1647-51
references.pmid: 12709335
references.citation: Clin Infect Dis. 2007 Feb 1;44(3):382-7
references.pmid: 17205445
references.citation: J Antimicrob Chemother. 2007 Sep;60(3):459-60
references.pmid: 17646200
references.citation: J Hosp Infect. 2002 Apr;50(4):243-60
references.pmid: 12014897
references.citation: Curr Infect Dis Rep. 2006 Nov;8(6):427-33
references.pmid: 17064635
references.citation: Eur J Clin Microbiol Infect Dis. 2007 Aug;26(8):541-7
references.pmid: 17569999
references.citation: Antimicrob Agents Chemother. 2008 Nov;52(11):4175-7
references.pmid: 18809944
references.citation: J Clin Microbiol. 2002 Mar;40(3):918-21
references.pmid: 11880416
references.citation: Antimicrob Agents Chemother. 2006 Apr;50(4):1287-92
references.pmid: 16569842
references.citation: J Clin Microbiol. 2001 Apr;39(4):1328-33
references.pmid: 11283051
references.citation: Diagn Microbiol Infect Dis. 2007 Jun;58(2):211-6
references.pmid: 17368806
references.citation: Future Microbiol. 2008 Dec;3(6):603-15
references.pmid: 19072177
references.citation: J Clin Microbiol. 2008 Aug;46(8):2620-9
references.pmid: 18579718
references.citation: Infect Control Hosp Epidemiol. 2008 Oct;29(10):978-80
references.pmid: 18715153