title: Multicenter evaluation of proposed standardized procedure for antifungal susceptibility testing of filamentous fungi.
abstract: A multicenter study was conducted to expand the generation and analysis of data that supports the proposal of a reference method for the antifungal susceptibility testing of filamentous fungi. Broth microdilution MICs of amphotericin B and itraconazole were determined in 11 centers against 30 coded duplicate pairs of Aspergillus spp., Fusarium spp., Pseudallescheria boydii, and Rhizopus arrhizus. The effect of inoculum density (approximately 10(3) and 10(4) CFU/ml), incubation time (24, 48, and 72 h), and procedure of MIC determination (conventional and colorimetric [Alamar Blue] evaluation of growth inhibition) on intra- and interlaboratory agreement was analyzed. Based on intra- (97 to 100%) and interlaboratory (94 to 95%) agreement for both drugs, the overall optimal testing conditions identified were determination of colorimetric MICs after 48 to 72 h of incubation with an inoculum density of approximately 10(4) CFU/ml. These testing conditions are proposed as guidelines for a reference broth microdilution method.
authors.affiliation: Medical College of Virginia/Virginia Commonwealth University, Richmond 23298-0049, USA.
authors.forename: A
authors.initials: A
authors.lastname: Espinel-Ingroff
authors.forename: M
authors.initials: M
authors.lastname: Bartlett
authors.forename: R
authors.initials: R
authors.lastname: Bowden
authors.forename: N X
authors.initials: NX
authors.lastname: Chin
authors.forename: C
authors.initials: C
authors.lastname: Cooper
authors.forename: A
authors.initials: A
authors.lastname: Fothergill
authors.forename: M R
authors.initials: MR
authors.lastname: McGinnis
authors.forename: P
authors.initials: P
authors.lastname: Menezes
authors.forename: S A
authors.initials: SA
authors.lastname: Messer
authors.forename: P W
authors.initials: PW
authors.lastname: Nelson
authors.forename: F C
authors.initials: FC
authors.lastname: Odds
authors.forename: L
authors.initials: L
authors.lastname: Pasarell
authors.forename: J
authors.initials: J
authors.lastname: Peter
authors.forename: M A
authors.initials: MA
authors.lastname: Pfaller
authors.forename: J H
authors.initials: JH
authors.lastname: Rex
authors.forename: M G
authors.initials: MG
authors.lastname: Rinaldi
authors.forename: G S
authors.initials: GS
authors.lastname: Shankland
authors.forename: T J
authors.initials: TJ
authors.lastname: Walsh
authors.forename: I
authors.initials: I
authors.lastname: Weitzman
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D005069:Evaluation Studies as Topic; D005658:Fungi / Q000187:drug effects*; D008826:Microbial Sensitivity Tests / Q000592:standards*
chemical_list: D000935:Antifungal Agents