title: Quality control and reference guidelines for CLSI broth microdilution method (M38-A document) for susceptibility testing of anidulafungin against molds.
abstract: The CLSI (formerly NCCLS) M38-A document for antifungal susceptibility testing of filamentous fungi does not describe guidelines for echinocandins. A multicenter study (eight centers) evaluated inter- and intralaboratory reproducibilities of two reading times (24 and 48 h or 48 and 72 h) and two end points (MICs and minimum effective concentrations [MECs]) for evaluating anidulafungin against molds. Anidulafungin MICs (>or=50% inhibition) and MECs (morphological hyphal changes) were determined for seven Aspergillus isolates (four species) and one isolate each of Fusarium moniliforme, Fusarium solani, and Paecilomyces variotii and for two Scedosporium apiospermum isolates. The inter- and intralaboratory reproducibilities of 10 replicate tests performed in each laboratory on 10 different days for each isolate was 100% at 24 h (MECs, <or=0.015 microg/ml) for six Aspergillus and P. variotii isolates. The reproducibility was 94 to 96.7% at 72 h (MECs, 1 to 8 microg/ml) for S. apiospermum and 96.7 to 97.5% at 48 h (MICs, >or=32 microg/ml) for both Fusarium isolates. Introduction of these identified optimum testing conditions for anidulafungin into future versions of the M38 document is warranted.
authors.affiliation: VCU Medical Center, 1101 E. Marshall Street, Sanger Hall, Room 7-049, P.O. Box 980049, Richmond, VA 23298-0049, USA. avingrof@vcu.edu
authors.forename: A
authors.initials: A
authors.lastname: Espinel-Ingroff
authors.forename: A
authors.initials: A
authors.lastname: Fothergill
authors.forename: M
authors.initials: M
authors.lastname: Ghannoum
authors.forename: E
authors.initials: E
authors.lastname: Manavathu
authors.forename: L
authors.initials: L
authors.lastname: Ostrosky-Zeichner
authors.forename: M A
authors.initials: MA
authors.lastname: Pfaller
authors.forename: M G
authors.initials: MG
authors.lastname: Rinaldi
authors.forename: W
authors.initials: W
authors.lastname: Schell
authors.forename: T J
authors.initials: TJ
authors.lastname: Walsh
mesh_terms: D000077612:Anidulafungin; D000935:Antifungal Agents / Q000494:pharmacology*; D025141:Drug Resistance, Fungal / Q000187:drug effects; D054714:Echinocandins; D005658:Fungi / Q000187:drug effects*; D017408:Guidelines as Topic; D007753:Laboratories; D008826:Microbial Sensitivity Tests / Q000379:methods* / Q000592:standards*; D010456:Peptides, Cyclic / Q000494:pharmacology*; D011786:Quality Control; D015203:Reproducibility of Results
chemical_list: D000935:Antifungal Agents; D054714:Echinocandins; D010456:Peptides, Cyclic; D000077612:Anidulafungin